General info
Temperatures & times for baking
Ovens (regular,toaster,convection)
Thermometers, testing your oven
Materials to bake on ...various
.......keeping flat items flat
Support during baking (propping)
...+ insulating (powders, etc.)
Darkening, scorching, & burning
.....avoiding darkening ... gen.
.....partially enclosing (draping... tenting)
.........summary of more ways to avoid darkening
.... enclosed baking (completely enclosed)
.....heat sinks to even out the whole oven temp.
.....baking taller pieces
.....remedies for burned items
Multiple baking, partial baking
Ice water plunge (quenching) for shine
Brief high heat for shine
Using tiles for high shine
Other ways to cure (or partially cure/stabilize)
....covered elec. roasters, frying pans, crockpots...+ solar ovens, heat guns, traveling, etc.
....stovetop "baking" in covered sauce pan w/ plaster
....boiling + microwave-boiling ... + "shine"
....controversies re curing temps, polymerization, etc.

BAKING

GENERAL info

Generally, polymer clay is baked in a normal home oven (regular or convection).
. . . some people have claimed it can also be boiled (on the stovetop or in a microwave)... for more about these methods, see below in "Boiling
"...however, for sure do not microwave without covering plenty of water!

Regular home ovens can certainly be used for baking polymer, but clayers who end up doing a lot of baking usually buy a toaster oven or convection oven. There are several reasons for this.
...There are smells from the baking clay which are totally normal (some clays smell stronger than others), so it can be more pleasant to put the (toaster) oven in the garage, outdoors, bathroom, or in another room, if you can and if you’re doing a lot of baking (see below for more on ovens).
......one way around this is to use "enclosed" baking . . . (see below for "enclosed" baking options). ..
.......I also found that baking soda will absorb smells in the oven (while I was baking clay in a pile of it). Helayne
.......other powders like cornstarch or flour, etc. can completely enclose the item too, and may prevent some smells? (see Propping below)
Also, something (possibly plasticizers from the clay) will eventually build up on the walls of the oven, and some people worry about baking food items in the oven afterward (see Safety-Cleaning for the discussions about this).

IMPORTANT:
..It's important to bake at a high enough temperature for at least the mininum time recommended to be sure that the clay will not crumble or leach plasticizer days or months later
.....so, make sure your oven is actually heating to the temp. that's indicated on its dial, that it stays at that temp, and that you bake long enough for the thickness of your particular clay item, etc. (...and see below if you're at high altitude**)
........ovens can vary up to 80 ° between the time the heating element goes off and it goes back on again (as much as 5 minutes). leigh

Any of the clays will crumble later if not baked properly...
...(raw) clay is full of plastisizers, they keep the clay soft... when you bake, you bake them off... but if you don't bake long enough, you don't kill off (solidify) all of the plastisizers... and when you take it out of the oven and the piece cools down, the plastisizors start to recover, and they go back to work starting to soften the clay... (because there are only a few of them left, it takes a lot longer, but eventually some of the clay gets soft and the piece will now get brittle and fragile... if it is then dropped, it might just fracture and crack and the least little pressure will break it apart!!!....
.......also those nasty plastisizors stay your hands also, and they love to eat the shine off of beautiful shiny finishes on finished pieces, so you shouldn't pick up anything with a beautiful finish on it without washing your hands eather!! leigh
....
(see below under "Multiple and Partial Baking", for opinions on whether partial baking creates a serious problem later... controversial)

In general, baking longer will result in a "stronger" clay item though the temp must not exceed the correct baking temp at any point (which is really hard to do --convection ovens usually work better for this).
...Baking longer at the same temp is not an option for the Sculpeys though because they darken even at correct temps (unless they'rll be painted over so darkness doesn't matter)... Kato clays will handle higher heats or temp fluctuations the easist.... Premo and the Fimos in-between
(...baking longer can be done at lower temps though since temp and time are interdependent for thermosetting plastics like polymer clay... see Controversies below for more).

for baking at high altitudes (over 3500'), see important info. below under Times and Temps.

how to tell if the clay is "done" after baking:
... it's important to know that polymer clays will all be somewhat soft when first removed from heating
....... they won’t reach their final hardness & stiffness until they're completely cool

AFTER COOLING:

...it's also a common misconception that polymer clay will be rock hard after baking and cooling (like earth clay will be)... in fact, the surface of a baked and cooled polymer bead can actually be dented with a fingernail if it's pressed really hard (this isn't really a problem, because after awhile clayers don't expect a hard ceramic feel for polymer clay)
...also, any thin baked clay will actually be flexible... this flexibility doesn't seem to be a problem most of the time
(.........for ways to stiffen thin clay when needed, see Characteristics > "Strength & Flexibility")
......most of the polymer clay brands are similar in this flexibility with the exception of Sculpey (Sculpey, SuperSculpey, Sculpey III)
and now also probably the new version of FimoSoft
.......those actually feel "harder" after baking which can be good, but unfortunately flexibility is also lost and along with it much of their ability to withstand stress (they will break or chip more easily if stressed)
......Premo, FimoClassic, Cernit, and Kato will be a little rubberier in feel after baking, but much stronger & more flexible
......(however, remember that fairly rounded shapes of any brand will be difficult to break just because of the inherent strength of the shape... but in thin or projecting areas, the Sculpeys & FimoSoft will be brittle)

Tallie created a baking surface for any pins with dimensional parts on the back side of an otherwise flat piece (...baking a pinback with a pin, for example, can cause the whole pin to bend-slump during baking)
... to avoid that, she makes a shallow box top and cuts a rectangular slot out of it, then she lays the piece on the box top so that the non-flat part sticks through (....would be especially good for larger pieces where fiberfill can't keep the item flat enough)
http://www.talliesplace.com/html/tools.html

Baking after sanding & buffing does affect the shine some, but all it takes is a quick rebuff and there you are, as shiny or shinier than before. DottyinCA

```````````````````````````````````````````````````````
FOR MORE INFO ON:
...how to bake other materials with clay (and whether they can withstand the oven heat), see the Covering page (under glass, plastics, metal, wood, paper, etc.)
......also baking eyepins and other connectors along with the clay, see Jewelry > Connectors.... Pendants-Cording > Top Loops
......also which glues and finishes can be baked right on polymer, see Glues... Liquid Clays.... Finishes

TEMPERATURES & TIMES

The minimum time required for curing is generally 15-20 mins per quarter- inch of thickness (at the thickest spot)
...some clayers also bake longer than the minimum time because they feel it makes the clay items stronger
...theoretically polymer clays can bake for days as long as they're maintained at exactly the correct temp (which is really hard to do given the fluctuations and hot spots of most ovens --but that's one reason "enclosed" baking works so well since it keeps that correct temp. much more easily)
...the light-colored clays (esp. Sculpeys) will darken more quickly than others, as will translucents or any clays with translucent in their makeup (not always obvious)

temperatures recommended by manufacturers (...slightly different for different brands):
... 230 -265 ° for the newest versions of the Fimos (see below for more*** )
... 275 ° for Premo & for Sculpey** (i.e., Sculpey , SuperSculpey, Sculpey III)
.......285 ° for Bake & Bend, and maybe other specialty Sculpeys?)
...275 -325 ° for Kato Polyclay (see Char's > Kato for details on which to use when)
..."between 215 and 270 ° " for Cernit (figures given on pkg)

***Eberhard Faber has changed the formulation of FimoClassic and FimoSoft (and their doll clays) --2007... these have gold on the packages
...the new version is softer and stays soft on the shelves (changed because some customers thought it was too crumbly)
...the package recommends baking the new clay at 230º (110º C)
...... BUT clayers have found that the old temp of 265º results in a stronger product for baking the new clay or mixes with the old clay
.........(2007) Eberhard Faber chemists and others have said that the new formulation does bake satisfactorily at (265º F) 130º C, and is stronger at that temperature. However, baking temperature (recommended on the package label) is judged by automated machines in the lab. The EU officials who regulate these things prefer to believe the machines rather than the judgement of human beings. That is why the label advises baking at (230º) 110º. Pat, Phillippa, Angie
......... if baked at 265, the colors won't darken any more than before
.............however,
some colors (translucents & light ones) always darken more easily (in most brands), so Fimo Soft's Translucent, Glow-in-the-dark, white with glitter, pearl and white may all need a slightly lower temperature (or tenting-enclosing?)
.....(the burning temp may be lower than the usual 385 for mixes or new Fimo's?)

However, time and temperature seem to be interdependent for the thermosettng type plastics.
--i.e.,
for every 10 C (18 F) increase, the polymerization rate will double-- see Contrversies below for info on using other times and temps

(so clays can be baked longer at lower temps rather than qicker at higher temps, but the temp will still be critical to avoid darkening especially for some clays)

**high altitude baking (over 3500-5000')
You will have to raise the temperature & also bake longer, just as you would for baking foods (true for any brand).
....I live at over 5000 ft ---I called the chemists at Polyform way back when because my things were not getting "done" ...pins would crack, polymerization was not complete.
.......He suggested that I bake at least 5 &deg hotter, and a little longer for altitudes over 3500-5000'
.......I use Premo almost exclusively, and now bake at 300 ° F for a half hour each 1/4" of thickness of the piece. Sarajane
....
I live at high altitude - 7,600 feet above sea level. When I first got really serious with clay, using Premo, it was breaking on me all the time, and I got very upset. I wrote to Polyform and was told that I need to bake my clay at 300 ° (for 30 minutes per 1/4" of clay thickness) to properly cure it ...my baked clay is now completely cured and very strong and I never have any problem with breakage
..... I keep two thermometers in my oven to be sure it stays at 300 °
......for clayers who live above 35000, it is very important to know this information so that there isn't a lot of clay breakage and frustration. Jackie S
....(for translucent, I do tend to bake at just a bit under 300F)

**Some clays or clay brands darken more easily than others, so sometimes these should be baked at slightly lower temps and definitely not too long
....most translucent clays will darken more easily
...............for over 3500 ft, though, just a bit under 300 F has been recommended for translucents
....the lighter colors of the Sculpeys (Sculpey, SuperSculpey, and Sculpey III) tend to darken more easily than other brands
....... and bulk white Sculpey actually turns a bit purplish rather than brown, with higher temps
(see techniques for avoiding darkening below in "Darkening")

To help keep ovens at the correct temperature (especially smaller ovens), if needed
....see below in Using Tiles to Steady the Temperature and also Enclosed Baking
....
since I keep my toaster oven in the garage to avoid baking smells, I notice that on cold days I'll have to set the temp gauge higher in order to get it up to the proper baking temp. Diane B.

For toaster ovens especially, pre-heat before putting your items in because many ovens will spike over the desired temp to quickly bring the whole oven up to the set temp.

partial baking --controversy:
...
I've noticed this phenomenon too....when I do a short 10-minute preliminary baking (at the normal temp), the final product, even though baked again for 30 minutes, is not as strong as something cured the first time for 30 minutes (true only for thicker items though ??).
...I understand that the molecules in the clay do not FULLY fuse if not baked at the recommended temp for the minimum recommended time, even if very thin,
and that the time is not cumulative, meaning it must be in one session ....so if you are working on a piece and bake at a lower temp to partially cure so you can add on, that is fine. But you must then do a final bake for the entire time (and remember then to take into consideration the thickness of the piece). Jenny P.

...The first bake (at the regular temperature) (& time?) IS the most important to make sure the clay has full strength . . later bakes can be shorter though. Jody & many others

...(for more opinions on whether partial baking creates a serious problem later .see below under "Multiple and Partial Baking")

Some people feel that (some or all) polymer clays can be baked differently, or at diff. temps, than recommended by manufacturers -- though these may require stringent baking conditions (so the clays won't darken too much,e.g.).
...Others believe one should never bake at higher than temps recommended by manufacturers.
...Others fall in the middle, or believe it can be done under some circumstances or with some clays but not others
(see Controversies below for more on temperatures & times)

1. I use the method of baking that Marie Segal taught me ...put the pieces in the oven cold...
... turn the oven on to 200 and leave the clay for about 15 min.... then turn it up to the full temp for the rest of the time for baking
....turn off the oven, and let the pieces cool in the oven
........this seems to create a greater durability, and I haven't burned or scorched anything in years
... The reasoning behind this is to bring both the inside and outside of the clay up to the 200 temp first, and then the final higher baking temp to complete polymerization... the slow cool is like annealing (sp?) glass beads or ceramics. syndee

2. flash baking for smaller pieces?... baking at 325 for 10 min (...no longer though)
....
I have heard that this type of curing gives far stronger and more flexible clay (325 is still below the "burning" temp of clay)
....will work for smaller pieces-- maximum of about 3/8" thick at most, and 2" long
... It is not recommended for larger pieces though because the heat will not have time to penetrate to the centre
....this works for Premo, but not for Sculpey III which will scorch
....this process seems to take the pieces up to a quick bonding

3. personally, I bake blends of Premo, Fimo, Kato and Cernit at 300°F in a home oven, or Oster toaster oven (not translucent, which I bake at 265, or Sculpey clays though) ... (if blends are mostly Kato brand, this temp would be fine anyway...or especially in a convection oven... not sure most ovens would be okay. DB)
...I have baked pieces that were white, ecru, pastels, other light colors at 300°F for over an hour (in one bake period--and sometimes with multiple bakes the total time has been over 3 hours)
...the key to baking at this temp is to use a traditional mercury style (liquid enclosed in glass tube ) oven thermometer... and to know your oven & check it every 10-15 min. SL Savarick
(.....see more of Seth's tips --and another method for baking at 290 ° in an aluminum roaster with two 6" tiles on the bottom:
http://www.polymerclaycentral.com/cyclopedia/baking_equipment.html )

clay can develop cracks (large or small) while baking, or cooling
...this is especially true for larger, solid clay items (more than 3/4" thickness), but there are other reasons too
(see Heads > Cracking for a full discussion of reasons, and baking techniques to avoid cracks)
.

OVENS & THERMOMETERS

The choices are: a large home oven (built-in or freestanding), a toaster oven (preferably in the garage or outside if possible), and a convection oven.

Many people prefer convection ovens because they feel the temperature is more even in all areas of the oven and that their items come out harder (however, these are expensive, and most toaster ovens will work just fine as long as the temp is correct).
....Convection ovens do cook food about 25% faster than regular ovens, so it's possible that using one with clay also strengthens it by baking the equivalent of "longer."

regular ovens

Many people use a regular home oven (with range, or wall mounted).

Since you're getting a new studio, why not buy a large oven? (and use it freestanding)
.....(mine is only a little smaller than a regular oven, but a good bit larger than a convection oven...it doesn't have a range
.....it's the kind that's usually installed in a lower counter, in some older kitchens.
.....I have mine in the laundry room, just down the hall from my studio, and with an outside door for ventilation.
.....You can probably find these used, cheap. Irene
..I would like to have more room to bake large items (like wall art, kaleidscopes, etc) than my convection oven offers, but are these types of ovens gas or electric, or both?....And if electric are they 220? Dotty in CA

Is this the same as a wall oven? (also used in a freestanding way)

I was able to buy a fairly large broiler oven for six bucks at a Value Village, our local thrift shop....yard sales are also a good source. Sharyn

(Is the water vapor part significant for polymer clay??)
...(I liked gas cooktops,) ..."but for cooking in an oven, I prefer the precise regulation and drier heat of an electric burner... gas oven by-products include water vapor." Mike

(see "Other Ways to Cure Polymer" sub-category below for other "oven" units and baking units)

toaster ovens

When buying a toaster oven, make sure it isn't "self-cleaning." Those will automatically spike the temp...
.....I've heard this before as well, and I think some ovens used to (or maybe still do) periodically "spike" to a high temperature in order to burn food splatters off the oven walls. (I would think this would risk toasting your dinner as well as burning food ON the oven walls, though...)
...
When I bought (was given, actually) an old convection oven at a yard sale, it said "Continuous Cleaning" on it, so I called the manufacturer for information. I was told that the wording referred to the fact that the oven interior had a non-stick coating -- it had nothing to do with the temperature -- and I have since found this to be true; it's a wonderful little clay oven. Bonnie

I purchased some of the 'best' toaster ovens ---at least more expensive toaster ovens-- and had a lot more trouble than with the cheapest ones which ended up being the best. I think part of the problem is that some of the more expensive ones are continuous cleaning and they spike continuously to clean. . . .the four more expensive toaster ovens were not even close to the temperatures that they should be.
....I've tried almost every toaster oven I could find....The $79.99 was the very worst and heated to 450 ° even when set at 200 °. My husband almost went nuts because he could not believe was not doing something right. But when he would try them (and use two diff. thermometers) and never get the same temperature left on the same setting, he finally believed me. . . .
.....(Plain old toasters are the same here. We must have purchased at least two a year and we always end up going back to the old types. The new ones just aren't consistent.) Jeanne R.

Someone suggested taking your thermometer with you to shop for ovens
... then ask if you can plug in your possible choices to check their temps somewhere in the store before purchasing, to avoid having to return them.
(...or steel yourself to the thought that you just may have to return a few before getting one you really like)

I have had very good luck with my Hamilton Beach OvenMaster, Model #31215. I purchased it about two years ago at Target for around $29 (it was on sale). Once it's preheated, it holds the temperature evenly, and the top element never comes back on to burn my objects. (As a matter of fact, it holds the temperature more evenly than my Faberware convection oven -- but I don't know if that's because the toaster oven is so good or the convection oven is faulty.) Shelly

I also bought the Oster large toaster oven with a timer on it for teaching..... it also has a large capacity
.......I have never burned anything in it so it doesn't spike. With the built in timer I can teach and not worry about watching the clock to take something out of the oven..... At Target it was under $60. Karen in FL
... I love my Oster too! Seth
... Now I have an Oster and love it. It has the timer and shuts off at the set time and I've never had it spike. It takes about 7 min. to warm up to my set temp. and stays there. If you can't get a convection then I recommend the Oster. It might cost a bit more but is well worth it. Nancy

I got a Euro Pro--it does very well at maintaing temp. MRS

Chroma-Tex oven...the URL does not state the interior dimensions, but it looks small. The site does state that it, the oven, is specifically for PC.. .. anybody used it? Bill
...looks like just a regular toaster oven that someone is trying to market to pc consumers.... I believe if you look around you will find a toaster oven at a better price, no s&h. Valerie

The oven is almost perfect. It is a Toastmaster Model TTOB4. Even though it was not expensive, it has features that make me think it was made just for us. You will need a good oven thermometer because the temperature gauge on the oven is a little off. But once you have it adjusted, the temperature is extremely consistent. The best part, though, is that the toaster oven has a 30 minute timer. I can set it for 20 minutes and a bell rings to tell me it has preheated to the desired temperature. Then, when I bake, I can set it for as long as I need (up to 30 minutes) and it will turn itself off after that time. . . . highly recommend this product to anyone who is thinking of purchasing a dedicated oven for clay. Dottie Hobbs
.......just doing a search on Amazon.com - brought up a small oven offered by Target that sells for $24.99 and has a 30 min. timer built in. mcs
...I bought a Toastmaster model 315..... It bakes about 70 ° above what is set on the dial and spikes extremely. I have to pull out all the tricks to get my stuff baked without burning. Before this one I had a Black and Decker, but I don't know what model and it was the best!! I never had a problem with it.

I remember reading a magazine article (I'm thinking it was Polymer Cafe, but not sure) and it was written by a well-known polyclayer ...she does a lot of traveling and has used a LOT of toaster/convection type ovens over the years.....I do remember the one she said NOT to get, and that's a Black and Decker. The reason being: temperature spikes..... Out of ALL the ovens, Black and Decker is THE one oven you can't trust not to spike! You could cure pieces in it for a month with your thermometer in it and it may be perfect. but eventually it WILL spike, according to that woman. Curika

Yes you can get toaster ovens here (in England)! Just look in your latest Argos catalogue (page 389) sometimes called mini ovens. Looks like a small microwave. New they are about £40 to £100, but I did manage to get one at a car boot sale (garage sale) for £1. I figured it was worth a pound to try even if it didn't work. Cleaned it up, put in a thermometer to check the temperature (which actually cost me more than the oven) and it worked fine. Shelley
... a toaster oven size would be around 50cmX25cmX35cm (could of course be smaller or bigger) so size-wise, it can be put anywhere you want ...on my visits to England I have seen different brands with different sizes. ruthyr

another suggestion: I have a convection oven that is dedicated for use with PC, and what I do is place it on my stove UNDER the vent hood (and turn it on)..... Even when baking liquid clay, we smell nothing. Patti

I keep my toaster oven in the garage .... and I notice that on cold days I have to set the temp higher in order to get it up to the proper baking temp. Diane B.

One thing to remember -- because the toaster oven is small, whenever the door is left open for more than a few seconds, it loses heat rapidly. So, after removing a batch, allow the oven a few minutes to come back up to temperature before putting in the next batch. (This is true for all toaster ovens.) Shelly

using a "heat sink" of some kind in the bottom a toaster oven will also help to keep the temperature exact, without spiking (see below in Using Tiles, etc., to Steady the Temp)

 

convection ovens

Ovens which don't have exposed heating elements and do have a fan that blows the heat created by the hidden elements around the inside of the baking area, are generally called "convection" ovens (even though technically, ordinary ovens bake with both "radiant" heat and "convection").

Convection ovens cure the clay more evenly all over because the hot air is really well circulated around the whole interior, so no hot spots.
... a convection oven brings food or clay itself up to the ambient air temperature inside the oven quicker than a normal oven would
....the fan is actually blowing away the cooler air that surrounds the surface of the clay (or food), allowing the heat to get to that surface quicker and more evenly

My translucent and white clays didn't turn color at all in the convection oven. Joy

The description of a Cuisinart convection oven on the website showed: "Convection, uses a fan to gently circulate heat, cooking "up to 30% faster" & more evenly." The 30% faster cooking is what I am concerned about. Lynn
...if something requires 15 minutes in a regular oven, it might only need 10-12 minutes in a convection oven
......but that's not an issue for clay baking because exceeding the length of bake time isn't a problem. Desiree
...It's the actual temperature that's important for polymer clay and the temperature isn't any higher in a convection oven than a regular one... it's just that the just the evenness and consistency of the temperature inside the whole oven is maintained better. So it's fine to use the same amount of time in a convection oven that would be used in a regular oven.

....Convection oven temps do vary a bit... I set mine so it won't go over 300 more than a few °, but always reaches 275 for some time. I'm not concerned if it drops lower for short periods of time
....... I used not only an oven thermometer, but test strips as well.... I marked each setting on the dial, and wrote down the setting and the different temps that it gave me over a period of a half an hour. Then I put in test strips at each setting. When they were cool, I checked to see if they were really well done (tough to break or tear) or slightly fragile, or more so.
...
however, if your oven's temperature is different each time you turn it on (at the same exact setting) then there is definitely something wrong and you should certainly return any oven that's doing that.
....... I just want to allay anyone's fears about the fluctuations that are a normal part of most all convection ovens. Dotty in CA

I now have two settings that I use most of the time.
....One reaches 275 a good part of the time (I use Premo) ...so far nothing has burned, and no breakage after baking
....I turn it up to the second setting for the last 5 minutes or so when I have used some liquid clay, but even if I don't do this and reach 300 ° the liquid clay still looks great and can be clarified more by plunging the piece into ice water when very hot and then sanding and buffing....the 300 degree bake makes this a bit easier, however.

(air blowing around inside ...oops)
...she had bought a round convection oven, the kind you can cook a chicken or turkey in (sort of standing on end.)
.....she made a half dozen clay-covered (hollow) eggs and put them into the oven and turned it on. A while later she came back to check them out and low and behold they were whirling around and around as if caught in a tornado. Guess the clay covering was too thin to weight them down.... No damage done, though. Dotty in CA
...might be a good idea to wrap the eggs in tissues or cotton fabric... maybe putting something heavier in the bottom of the wrap to give them just enough weight not to blow around, or wedge the covered egg(s) into an open box or between two mugs, or tape the wrapping down, etc.
.. clay items hanging on sticks, in glasses, or other ways have a tendency to dance and swing
... ...
if they aren't isolated somehow, they may also bang into each other or knock each other over
...things on the top shelf blow around, so I only fire heavy stuff there and I fire lighter stuff on the bottom
..... if and if I have nothing on the top, I use a tile on the shelf which kind of blocks the bottom shelf from the wind effect

...I didn't have any problem with the polyester stuffing as long as something is on it to hold it down. Judi
....if you use paper or parchment to avoid shiny spots, you've got to weight its corners
...
With the really small pieces, I found putting them on ceramic tiles works well (they kind of get stuck on). Judi
...(use an enclosed method)... with convection ovens put your item in a disposable aluminum pie pan, put another disposable pie pan turned over on top of it and clip it shut, that'll keep the air from blowing your mini things about. Nora Jean
...when stuff like embossing powder was involved, the blowing air issue was problematic . Irene
....shrink plastic also isn't a good idea because of the wind. …faun
(....you still need to make sure you prop things like arms and tails just like in a normal oven)

The dial on mine starts at 300 but once I had calibrated it, I marked the 275 range w/ a sharpie. Laurel

My nine-year old (older) convection, which has always baked perfectly, is aging now and I find that the temperature tends to creep up.... So I check the thermometer with each load, about 10 minutes into the baking, then make adjustments if I have to. Dotty in CA

The manual for this convection oven uses Asian characters..... It took me a while to figure out how to assemble it, and I have this metal thingie that I'm not sure WHAT it's for. Laurel

My solution to geting a good convection oven might help... I frequent estate sales. Most of the time there are all of the kitchen appliances available cheap.
...You do have to be careful.. ask if you can check it out, and bring a themometer.... I got my convection oven for $30, and it was so clean it looked brand new. Patricia in Tx

Some of these are often offered on E-bay. Just be cautious, and check out the seller's ratings if you go that way. Dotty
....I've heard a lot of people have had problems buying a convection oven on e-Bay. ....these items are not under the "as is" law, and are expected to be able to be used for the purpose they are purchased. (And that shipping amount is outrageous. I've finally stopped buying from anyone who charges more than a few bucks more than the actual postage). DottyinCA
....I second what Dotty sez! I've had good and bad experiences with sellers and these ovens on ebay. . A couple friends of mine received broken ovens as well....my advise is ask questions first! Georgana

Another thing to think of with the Welbilt, and maybe other convection oven brands, is that they have heating elements on the top AND bottom of the oven. You need to be careful which setting you choose, as some use top element, some use bottom, some use both, and some use alternating. I use the "roast" which I believe activates the bottom element. . . Between the elements I have the pan it came with as well as 2 tiles so there is no direct heat coming from the element. If I had broil on, I know it would scorch whatever was in there, no matter what temp it was set at. Lori

The kids and I enjoy claying in the car (on vacation) and the small convection oven fits under the car seat to bake up what we create. I have used the car dashboard to warm/soften clay.

specific brands

Hamilton Beach convection oven, model 31197....I picked one up at Sams Club the other day. kathie
....I love my Hamilton Beach. I got mine at Target for $88, but don't know the model number. Lynn
....I have that model...itt holds a steady temp like nobody's business...shuts off when the timer rings. Mine, at least, is very dependable, & I like the size. Marla
....I have a Hamilton Beach Model 31198 that I purchased from Target last December and I like it very much....keeps the temperature accurate and is very roomy (I'm guessing # 31197 is probably about the same type). Janet

(Isn't it one of the no-longer-available Welbilts that's supposed to be really good??)

I have (a Welbilt from Service Merchandise) . I am on my second one, and this one is going back to the store soon They both have had very flakey thermostat/temp control. One use the 250 setting will heat the oven up to 275, the next time it may go up to 305, the next time it doesn't even get to 250, then I adjust the knob to a hair past 250 and I get 311! I have to keep an eye on it every time I bake something! And I have yet to find a place on that knob that will get to 300 and stay there. (The LS requires a temp of 300.) . . . Service Merchandise's policy is SUPPOSED to be that if a sale item is not available in the store, they are suppose to offer to ship it directly to you FREE of shipping charges. I have found some store people quite willing to honor this, others, I have had to get a bit more "persuasive" or just ask to see a manager….I have heard that this is a good oven, I guess I am just getting all the imperfect ones! :-( Kimba

This was my experience as well. I tried 2 Welbilts from Service Merchandise and returned both, ending up with a comparably priced Toastmaster which seems very steady and reliable. One of the Welbilts I got almost seemed to have no thermostat at all. Even on the lowest setting, it would zoom up to 450 in no time at all. I must say their return desk was very good about it both times. Halla

Jan 02 --I bought the large one off the Toastmaster site. I LOVE IT!!! It's so much larger than my old toaster oven. ...No hot spots, either, thanks to the fan. I recently made an 8" tall vase, and it fit very nicely in the oven. I know some people have had issues with Welbilt, and mine is still pretty new, but so far, I give it 5 out of 5 stars! . . . One surprise I found--this one really has a strong fan. If I want to tent anything with foil, I will have to weigh the ends down. Judi
...I bought a table model Toastmaster convection oven over 6 years ago. It holds more than a regular toaster oven, but I can still pick it up to take to the classes I teach. This convection oven does not blow around paper or polyfill if I use it, just a gentle air circulation. It cost right at $100
.......It has a wire rack, which I place a sheet of parchment paper on or a manila folder to place my items on...the other rack is a broiler pan with a drip rack insert. ......Under the rack in the broiler pan is where I placed some standard sized tiles ...I had measured the width and length and found a couple of tiles that would fit --no cutting necessary-- which helps maintain an even heat.Patty B.

I just heard about a toaster/convection oven by Europa at Target for about $50 that is smaller than a standard convection oven but larger than a toaster oven. I do not know any more about it, but am going to look into it. Patty

These (Farberware only?) ovens http://www.hfse.com/Farbwr.html ... if you need parts, these folks are very helpful. I myself haven't ordered from them, but friends of mine have.
....Tip: Harsh oven cleaners are NOT good to use in these ovens...mild soap and water is recommended. Georgana

comment in the description of the Cuisinart TOB-175 Convection Oven (as listed on appliances.com.): "This unit can be and has been used as a kiln for polymer clay. Please note that it is not recommended to bake clays in the same unit that will be used for food consumption." ...I don't think I've ever seen a manufacturer list the use of their item for polymer clay. I was impressed.... This convection oven apparently beeps when it reaches the temperature the user has set it to (though I would check this with my own oven thermometer,) has a timer, and shuts off after four hours of continued use (maybe a disadvantage?) Amy

the American Harvest is more accurate. And if it comes with an expansion ring like mine did, you can bake taller items. Tonja

I have the Sharp Carousel Convection-Microwave combo and have used it for cooking the clay with no problems!!!!! I have never over cooked or burnt anything in it. You cannot accidently microwave it without an effort. (There is a pad you touch for convection, and you have to touch something entirely different for combo or microwaving and they are CLEARLY labeled!) You set the temp you want each time you start it up, so there is never the worry that someone else messed with the temp settings without your realizing it. You set the timer, and it shuts off when the time is done and you don't have to worry about forgetting to turn it off on time. Can you tell I am happy with mine? ;-) I really do feel comfortable recommending it. :-) Kimba

One of the 12 qt. Nesco "roasters" uses convection (..... looks a bit like a large crockpot, but wider)
....I just LOVE my Nesco with its hidden coils! ....The lid's fan is on a separate plug, too, so I can use it with or without.... it maintains temperature great... easy to clean, too..... I got mine on eBay for $50. . . mine's turquoise (but there are other colors). I can't begin to tell you what a perfect oven this is for our purposes. Kelly

I tried a 2nd convection oven on e-bay, this time paying a little over $50 for a Jetstream w/ a plastic body & an expander ring. I eagerly clipped a candy thermometer to the tray so I could calibrate it for clay. The thing blew stronger than a blow drier for about 5 min, made an awful smell, and conked out. It never worked again. Not sure if the strong fan winds were a malfunction, or characteristic of this oven. Laurel

Our local Value City department store has Toastmaster Ultravection ovens for 30 bux.....Unfortunately my tests with it have failed miserably... The oven comes only with preset buttons and all of them are very high temps... Dave
...My sister bought one of these for me and they are NOT good for PC. These are the ultravection ovens from the 'as seen on tv' infomercials. There are no temp controls. I tried to bake some clay and about 90 seconds in, my kitchen was full of smoke....the clay was burning. They may be great for cooking pizzas but not good for pc. Christine

(info too old, unless buy at garage sale??) 7-29-00...... discussions re various good convection ovens
http://groups.google.com/advanced_group_search .....then enter Re: Convection oven - need input!
in Subject field, & rec.crafts.polymer-clay in the newsgroup field

THERMOMETERS

photos of various types of thermometers
http://www.amazon.com/exec/obidos/tg/browse/-/289807/ref=br_lr__2/104-5966068-4359901
(click on Candy and on Oven-Frig)
...make sure any thermometer you use with clay can handle at least 200-325 °

When you first get a toaster (or other) oven, sit and watch exactly what happens as it goes through the baking time
.......this will tell you if your oven dial is accurate, or if not how much it's off
...... if your oven spikes its temp, this will show when, and for how long.
.......you can also move thermometer around to diff. places in the oven to see if you have hot spots in your oven

Once you know about the temp. of your oven, then you may want to place the thermometer in the middle, or toward the back
......or i
f you have trouble with some clay areas darkening, be sure to put your thermometer fairly close to the clay (rather than off to one side of the oven) because any hot spots in the oven may not register on your thermometer otherwise.

.."pre-heating"....ovens take more time than you might think to reach the temp. you've set on the dial
..."a preheat cycle only gets the oven temperature close to where you've set it... to get an accurate reading, let the oven cycle on and off at least three times, which takes about 20 minutes (in a regular size oven)". repairclinic.com
.. 'acceptable range' of operation... even the best oven thermostats have one...most manufacturers consider a thermostat in perfect working operation if it can achieve an oven temperature within 25 ° of what you've set it to... " repairclinic.com

TYPES of thermometers:
Most clayers use a $5.00 (round, dial-type, metal) oven thermometer (can buy at grocery store)
...most of these thermometers can stand alone, or hang from one of the oven's shelves

You may get even greater accuracy from a glass bulb oven thermometer (with mercury inside), which costs $8-$15 ... some have stands
http://www.repairclinic.com/0047_13.asp
...some candy and/or deep-fry thermometers are the glass bulb type too
......I find candy thermometers reliable.... just lay down on the rack in front of the items curing.... I have to get up close to read it though. Valerie
...
.couldn't you just make a holder for your candy thermometer with polymer clay?... then it could lay on its side or stand up

digital ... probe thermometers especially (for knowing when item is fully cured)
... I just bought a new oven thermometer. It's digital, with a probe that goes in the oven and the readout part that you keep outside. It's really meant for roasts & turkeys... the thermometer has an alarm that goes off when it reaches a set temp (ie: 275 °), and, voila, no more burning!! ....It also had a timer with alarm on it. I love it. It was expensive ($24), but if it means I won't burn stuff, its well worth it. Claire
...probe thermometer, Radio Shack, $19.95 ….that one has a stand and a magnet so you can see the temperature and time display where ever it is convenient. You can set a desired temperature and time, and an alarm sounds when it is reached. The probe fits inside the oven with a 3' insulated wire coming out of the oven. (Yes, the door closes easily on it.) Patty
....I got mine in a kitchen and bath store like Bed, Bath and Beyond... leigh
...You can get them from Amazon.com. I got mine on sale there.... one good one is Pyrex... another is Taylor. Sarah
....http://www.amazon.com/exec/obidos/search-handle-form/103-9078918-2147067
...I tried wrapping my probe in polymer clayand after a while it stopped working entirely (???). Lenora
......I wrapped the probe in tin foil and then a layer of clay. When it reaches 275, I know my actual pieces have cooked all the way through. Claire
.. I find the probe needs to sit INSIDE the item cooking (does not do a good job on the ambient air temp)??. Valerie
.........I just lay the sensor part on the tile I use towards the back of the oven, works fine (???). Valerie
...btw, the probes on these digital thermometers though will eventually be damaged-melt if used (frequently?) at temps over 350°

MISC:
If you have trouble reading the temperature on your thermometer
...
you can add clay markers onto the thermometer next to the correct baking temp's you might want, so that you wouldn't actually have to read the numbers (....to avoid using glue which might degrade in the oven, it could probably be attached over the edge of the face or have some other mechanical hold)
......some temps you might want to mark are those for hardening Future or Varathane (200-250), baking Fimo (265), baking Premo (275), baking Kato (300-325), curing liquid clay (for a short time) (300), and maybe lower temps for all-translucent clay or for some original Sculpey or SuperSculpey

...or you could use a large, *glass* magnifying glass to see the temps more easily... it
could be set into a little stand of polymer clay for holding in front of the thermometer (the farther apart they are, the greater the magnification).
.....removing one lens from strong (3.0 or higher) drug store reading glasses should also work as a magnifying glass.

.......it's also possible that a drinking glass of some kind has the right curvature to act as a magnifying lens and could be placed in front of the thermometer. Diane B.

calibrating a thermometer
...unfortunately my thermometer reads 195 ° in boiling water (212 ° *at sea level*)... so I have to keep my oven at "250" on its dial to get (about) 265 for Fimo and at "260" to get 275 for Premo. Susan
...put your candy thermometer in boiling water .... should be 212 F at sea level (or 100C) ...some may be off by 6-8 °

The quality of oven thermometers is not equal
.... Also, even if you get a good one, you'll need to replace it (????) after a few month's use... the springs in the mechanism get worn and floppy with use... no longer accurate. I buy a new one every 4-5 months. (I'm not talking about the digital probe types, just the types that are commonly found in the kitchen gadgets section). Elizabeth

TESTING your oven

calibrating an oven:
...turn on the oven to 350 ° with your oven thermometer inside
...remove the dial ...there's a slotted shaft that the dial normally sits on, so see where the slot is pointing and make note of that
...when the light goes off signaling that the oven has preheated, check your thermometer
.....if the thermometer says 300 ° instead of 350, turn the slotted shaft until it points at 300 using a screwdriver (...so when you replace the dial it should be pointing to 300 ° --it matches what's inside the oven and out.) Meredith

Someone also suggested doing an experimental bake in your oven to discover where the "hot spots" might be:

...make even-sized clay tiles from a light-colored polymer clay ..... place them in your oven in a grid-like pattern.
......bake at your usual temp, then record which ones darken the most or see if you can discern any pattern
...put samples (clay pebbles) on a tray or big piece of parchment or tin foil evenly spaced end to end and side to side. See how your oven bakes them. Does your oven brown them in any area? Or is it even?

(OR. . . . In order not to waste clay, you can lay slices of bread side by side, covering the bottom of the oven, and watch for hot spots as the bread burns- um, toasts. Nancy ... won't tell you much about your oven's temp accurary though, only the hot spots)

(....you can do this for different heights in your oven too, particularly for a toaster oven).

My oven (also has hot spots which can burn the clay).
....What I do is lay the thermometer probe or just the thermometer itself depending on the type on the tray that is being baked to get a better temp reading... I think this makes sense.. :) I haven't had any burned clay since I started doing this... Dave

Unfortunately, most toaster and regular ovens (as well as convection ovens?) can be variable in performance temp-wise, and it's really hard to know beforehand what you've got. That's why we all have oven thermometers!
......it may just be that your oven is in a drafty spot ...or that one side is just more protected than the other from the cold/heat
.........this can even happen inside when the oven is near an open window or open area... but esp. outside or in a garage
.....for outside, try locating your oven in a more generally protected area from the prevailing winds
.... or maybe put the oven in a large cardboard or wood box (leave box open on more protectedsides). Worth a try?? Diane B.

On most toaster ovens if you will place your work close to the righthand side of the oven you will have a more consistent bake. Why? Because the thermostat/sensor is on the outside of that wall.

Maureen Carlson told me in all of her classes, always put a sacrificial bit of clay in with the peice you are baking
...pull it out & let it kool (i'l put it under cold water ) then break it.... if it is crumbly it has not baked long enuf.
...slicing it hot with a razor blade will be a good indicator too.....put the rest back in and try again, or have more than one to tear up.

MATERIALS to bake on

Baking can be done on various kinds of oven-safe materials, but some things need to be kept in mind:

Polymer clay will soften slightly when it's hot, so placing clay directly on a very smooth surface (like glass, metal, alum.foil, cermic tile) will result in a shiny spot on the clay wherever the smooth surface touched it.
.....so if you don't want your baked sheets to be shiny, use something like terra cotta tiles (rather than the smooth ceramic ones), or simply place a sheet of paper between the your shiny tile or other item and the clay.
....or you can always sand off the shiny area(s) with sandpaper or steel wool --then buff a bit when necessary

Ordinary paper has about the same "texture" as baked polymer clay, so many people place their clay items on a sheet of paper
(....the paper is usually placed on top of a flat stiff surface like a tile, glass, or metal baking sheet)
.........(it may be okay to put the paper directly on the floor of some convection ovens?)
.........paper may also be accordion-folded for baking pens or beads (in the troughs)
...........accordion-folded paper can also be used to elevate other baking surfaces farther fr. lower baking coils to avoid darkening
...parchment paper is also used by many clayers
...... some of the parchment papers in the US come with a silicone coating though (...usually says on the outside of the box) ... clay baked on that type has difficulty holding findings attached later with glues ( took me a while to figure why my pin backs were falling off) ...mostly the recycled paper at gourmet grocers will have this kind...so they're great for cookies, bad for polymer. Cary
...patty papers (to separate hamburgers) and deli sheets (lightly coated with ____) are fine for baking on too
...index cards & manilla folders....
I have used both 3x5 and 4x6 index cards quite successfully for baking on.
......however, I once used brightly colored (florescent pink, fl.yellow) index cards, and the color transferred to the clay bottom! (...I sanded it off). Patty B.
...it's poss.that at some point, these may warp just a bit tho, so maybe not best when a totally flat result is desired for a thin sheet of clay (unless weighted)
...... beware of chipboard-type cardboard which can sometimes warp in heat (...and especially if there is a coating/paint of some kind on only one side, like a cereal box).
....tissues (Kleenex, etc.) and soft paper towels work well too, and can also be used for making a nest, or propping, etc., without leaving marks

NOTE: ceramic tiles & metal baking pans may heat up a bit more than the surrounding air
....... so (especially in a toaster oven, or if using translucent clay) you may want to raise them up a bit from the bottom coils
....... or put a few layers of paper, paper towels, fiberfill, etc. on top of them before adding the clay
........or insulate them with cornstarch or another powder (see below in Support, Propping, Insulating)
...I checked my toaster oven temp again, but this time WITH the metal baking tray I had been using...there was at least a 10 degree difference! vbratton

metal ....cookie sheets, cake or pie tin, etc.
.....
(if you do use a cookie sheet without a sheet of paper covering it) be careful that it'sis not the so-called non stick material that is NOT Teflon but a kind of shiny grey coating, which does really NASTY things to polymer clay...like pitting it. ...with flat objects like pendants and pins it doesn't matter but with items that can be viewed from all sides, it's a disaster. kelly
.... I use those CD tins that AOL sends in the mail for baking trays because they just fit next to the thermometer (and they're flat). Trish
....some disposable aluminum containers have flat bottoms (but some have impressed writing), or they could be used with a layer of batting
....aluminum foil (unwrinkled)
(...note that if you bake on a smooth metal surface, your piece will be shiny on its bottom unless a sheet of paper, etc., is used between)

tiles (shiny ones, or not-shiny like terra cotta), can be used to bake on and have some advantages
...using a tile is often a good idea anyway because your piece will not then need to be removed or handled from the working area into the oven ... can have a number of diff. tiles going at the same time
...
I would recommend that you not bake any translucent clay directly on a tile since it browns or yellows very easily (if the clay is made even hotter by resting on a tile , this can cause it to go brown even quicker... so I insulate my transluent will paper towels and/or cornstarch. Jana (for cornstarch, see below under Support and Propping)
(...note that if you bake on a shiny tile, your piece will be shiny on its bottom unless a sheet of paper, etc. is used between) ...more below on using tiles
...
(for using tiles in other ways when baking, see below in "Using Tiles to Steady the Temp." and also "Using Tiles for a Shiny Finish")

sheet of glass (from a photo frame, etc.).... glass baking dish ...ceramic plate
....if you want something with a lip which you can wrap aluminum foil around for tenting an item or for enclosed baking, you can create a lip around the edges of the glass with some clay

(...note that if you bake on a smooth glass surface, your piece will be shiny on its bottom unless a sheet of paper, etc., is used between)

I bake on separate tiles or on a board called "clay board"... it's like particle board that has one side covered with a certain kind of clay. I use it to bake on because it does not leave a shiny spot on anything I bake on it.
.... these are purchased at art stores (altho recently I have seen black clay boards at our Michaels.... I don't recomend the black though.)
.... there are several variety of these boards.... the one that is the best is just the "original" clay board. Bean

Teflon sheets ...you can bake on them and the clay will not stick to it... I'm not sure of any advantages over other surfaces. Kathndolls

Nanetta makes "holders" for baking round or tube beads from polymer clay (rectangle, #1 pasta machined)
....for round beads, she impresses a grid of shallow, rounded depressions created with a marble (press in, twist out)
....for tube beads, she impresses the clay with a dowel, knitting needle, round pencil etc.
..(as a built-in release? for baking beads) she powders the holder with talcum powder (heavily?)
...bakes holder ... brushes off extra powder... (then bakes her raw beads sitting in depressions)
http://www.pcpolyzine.com/2005june/nanetta.html

polyester stuffing and batting:
...a "cloud" of stuffing or a sheet of batting is great for baking many kinds things, and can be used on top of a baking tray, cardboard sheet, etc.
.....it prevents flat spots on items, and helps support the parts (especially of odd shaped items)
http://tutorials.theclaystore.com/techniques/firing-a-standing-polymer-clay-doll
.....it also helps to insulate the item so the temp. underneath doesn't get too hot, so can also use on top of any thin or projecting areas
.........(esp. good when baking translucents and some light colors of clay)
...sometimes little "hairs" from the polyester will stick to the clay after baking, but it's fairly simple to remove them and doesn't hurt anything
(see below in Support for warnings about using polyester safely)

keeping items flat

You'll often need a very flat baking surface to keep items flat, or flat just on the back
...especially when baking thin sheets of clay, which are more susceptible to warping than thicker clay
(very flat baking surfaces would mean for example, a glazed tile, a sheet of glass, a metal cookie sheet, cake or pie tin, a glass baking dish, etc.

For making really sure they'll remain flat, clay can also be weighted during baking and cooling
...you can use anything that's heavy and untextured, and oven-safe
......(always place a sheet of paper between the clay and any surface it will be touching unless you won't mind a shiny area there from baking against a very smooth surface)
.....weighting clay during baking & cooling will also help prevent air bubbles from rising inside the clay. . . (if there had been any air or moisture in the clay)
........when I bake something that's flat, I bake with it's front side downward so that air rises to the back of the sheet (and won't show as much).... obviously I can't do that with a dimensional object though. Elizabeth
......if you're concerned about hot spots developing in your weighting item (if it's metal... or perhaps hot spots in your oven could cause certain parts to get hotter), you can use a tent or enclosed baking method Including powders), or use a weight which doesn't conduct heat as well (like wood, glass) ...for those you may need a sheet of paper between though (see more in Other Ways to Steady Temp below)

..If added weight would harm or squash your surface technique, (just bake it with the back as flat as possible, without weighting), then wait until the pieces comes out of the oven
... while it is still somewhat hot, place heavy books on top of it until cool. Dotty
..Or if the surface is embellished with onlays, etc., while it is still fairly hot but not so much so that you can't handle it, fill the sink with cold water and then lay the piece down on the bottom of the sink and hold it flat wherever you can until cool. Dotty

You can actually hold the raw clay flat during baking by "sticking" the clay down onto a very smooth surface (glazed tile, glass, etc.) ......(press the clay down firmly against thebaking surface before baking)
.......doing this will cause a shiny area anywhere the very smooth baking surface touches, but if that's only on the back side of the piece it may not be visible later (...if later gluing a shiny area to something else, rough up the shiny area )
....or you can create the piece on the tile in the first place so it will already be stuck down (rather than placing it there just before baking)
...using the stuck-down techniqe is also one good way to prebake a bunch of Kemper cutout shapes to use as inlays, etc
.....to do that, press a sheet of clay onto the tile, then punch the shapes into the sheet but don't remove them
.....when all shapes have been cut, then peel off the excess clay which will leave only the shapes stuck to the tile... bake ... then pop the shapes off the baking surface. Bean

To make one side of a piece really shiny on purpose, I've seen some clayers press their flat beads, for example, tightly to a cookie sheet or glass plate. Marty
...or make both sides shiny intentionally by using a very smooth item both under and on top of the flat clay during baking

Support during baking ... & Propping
(....some will also Insulate....)

If the item to be baked is dimensional and not flat --such as a sculpture, a barrette or curved pendant, or just any item you want to hold its shape
-- there are various oven-safe materials that can be used as temporary support for shaping clay, or draping clay over, during baking:

....paper based products (cardboard or carboard tubes, tissues, plain paper... wads, folded, etc.)
...unfinished wood
...natural fabrics like cotton, muslin, etc. (wadded into a nest) ...or one of those placed over another armature
...
polyester stuffing or batting ... a "cloud" of it, which is placed on a baking pan (...will not "melt" at 275 ° unless too close to heating coils)
...hard, smooth surfaces (like metal or alum. foil, or glass ...cups, mugs, etc.) can be used, but remember they will create shiny areas on the clay after baking any place they touch the clay while baking
.......however, those hard smooth surfaces could be covered first with a piece of paper or a tissue, e.g.
.......or the shiny areas might be created only on the back or bottom of the piece, which wouldn't be a problem
...piles of powders, or fine grains, etc.

Sculptures can be baked on their feet, but any long or heavy and protruding bits (like an extended arm, dragon neck) should be propped with soft fabric or batting, e.g., to keep it from drooping during the baking process (see more on "propping" below).
(...some items that *seem* to stand up fine before baking may lean a bit after heating –make sure your figures in particular are well balanced before baking.)

For larger polymer pieces, I do like Pier and make a "nest" of fabric sheeting ( twisted into coils basket style) to give support for the side walls. Linda WTX

polyester stuffing and batting:
...a "cloud" of stuffing or a sheet of batting is great for baking many kinds things
.....it also helps to insulate the item so the temp. underneath doesn't get too hot (esp. good when baking translucent clay)... and can also put some on top of any thin or projecting areas (of sculpts, e.g.)
...sometimes little "hairs" from the polyester will stick to the clay after baking, but it's fairly simple to remove them and doesn't hurt anything
...most of what I make are boxes with a lot of decorative elements added in the course of several bakings... to ensure that the box doesn't collapse inward from lack of support during baking, I usually put polyester batting inside. Once, I decided to be extra sure
...so I really stuffed the polyester fiberfill or batting into the boxes, instead of filling it loosely... the boxes didn't collapse --they exploded!
.....my guess is that the expanding air couldn't make it's way up through the too-dense polyester, so it pushed out through the sides of the boxes....so at least allow for the air to escape. Irwin
....the other problem with stuffing the inside of a vessel too tightly is that when the clay starts to warm and soften, the pressure from the tightly stuffed batting itself pushing out on the walls could cause the seams to separate or the walls to bow outward. Dawn

cautions for batting and stuffing:
.....little bits of polyester may cling to the baked item, but they can easily be pulled off

....... I place a layer of an old cotton sheet on top the batting Linda..
....
all battings are supposed to be non-flammable by law because they are used in stuffing kids toys, but now and then some products from other countries manage to get in that are illegal.... so check the packaging if it's an off brand
...don't let the batting get
close to any part of the heating elements
.........don't put too much batting under your piece (so it won't raise item any closer to the coils than nec.)
...of course, be sure you have the toaster oven on Bake,
not Broil (the only batting fires I know about have been caused by this mistake). Dotty
..I also had a toaster oven
malfunction one time too .....the clay had only been in for a few minutes. Helen

PILES of powders or fine grains of anything which can withstand our baking temps... for example:
...cornstarch... rinses off more easily than wheat flour
......I use it as a support medium and also as a temperature "stabilizer." I use a toaster oven for baking and have placed a tin filled with cornstarch on the tray. I place the clay project into the cornstarch, making sure the bottom and "empty spaces" are well supported by, and the top is covered with at least 1/2" of cornstarch. ...After the oven thermometer shows that the correct temperaure has been reached, I start timing the clay.... Using this method, I have NEVER burned/discolured a project, or had the "long skinny pointy out bit" sag, even without an armature wire, even using sculpy.
.........then I either leave the project in the oven to cool down, or drop it into a sink of water to wash off while hot. Either way works fine.... just add more as needed.
.........the only downside to the use of cornstarch is that it tends to be a bit messy because of how fine it is; it tends to "fly" over the counter while being handled but is easily cleaned up with a damp cloth. . . . I have not baked liquid clay with cornstarch, so I do not know how that would work. Humm... Peggy
...I bake all my beads in a pan with about 2 inches of cornstarch flour - it doesn't matter if the beads get more or less covered with it as all you have to do is rinse them under the tap after they are cured.
........and you just store the pan in a cupboard, covered with foil and use again and again, replenishing it when the level is too low ...very convenient! Marie
....here's how I bake items (esp. with translucent clay, which is easily darkened or scorched):
....... if my item needs to be baked on a flat surface, I lay 3-4 paper towels on my tile.... then I lay the clay item on top of the paper towels
.......then, I scoop up a spoonful of cornstarch and gently sprinkle it over the item, until it is totally covered (at least 1/2" thick)
...........the cornstarch is wonderful for keeping your translucent from browning or yellowing since it totally protects it from the heat of the oven (insulation)
....... if the translucent isn't clear enough after baking, I put it back in the oven for about 5 min (without the cornstarch)... this will clear up the translucent if it needs it, without browning it.
..... If my item doesn't need a flat surface for baking (beads, etc), I put them in a baking pan which is always kept filled with cornstarch
........then cover with cornstarch and bake as above. Jana

...flour (wheat)
...baking soda someone suggested I upgrade from flour to baking soda - which I have done and it is superior - also absorbs the odor during baking, but also I found it much easier to wash off the finished piece than flour.
.......the other bonus(?) i found with the baking soda over the flour was it seems to give the clay an interesting slightly pebbled texture that I like. Helayne
....by pouring baking soda under, around, and on top of the clay before baking, one is able to protect thin pointy parts of the work from drooping and or burning, and also aids in temperature control (a pan with walls is helpful)
.......add extra baking time to allow for the mass of baking soda to warm up. Peggy
..I'd like to add to that list with diatomaceous earth (DE) which not only provides great support for polymer clay items, but is also a wonderfully effective non-toxic pesticide.... plus it is inexpensive
.........diatomaceous earth is a powder composed of the broken shells of tiny weeny diatoms.
........I purchased a huge about at a local hardware store...should also be able to find it at pool supply stores as a water filter for pools. .
........I filled up a deep dish with DE... then covered it with tissues (or cotton cloth) which form a thin flexible barrier between the clay and the DE. ...then I gently nestled and pressed the polymer piece into the tissues
.......since DE is basically silica, polymer clay baking temps won't bother it at all.
...... links that provide more detail about DE: http://www.internet-grocer.com/diatome.htm & http://www.perma-guard.com/. Desiree
...even sand or edible fine grains like couscous or rice or might work if they didn't leave marks through tissues or cloth which could be laid on them, and didn't smell or burn in the case of grains

propping

Although liquid clays and Diluent are superior "glues" between two pieces of clay, they have little tackiness or holding strength if used alone
....so prop together pieces to be joined during baking (unless gravity won't affect them)
....to actually hold the joined pieces together long enough during baking to allow the liquid clay or Diluent to work, the easiest way is just to use a few dots of superglue alongside (not on top of) the liquid clay or Diluent
...see above for materials that can be used to hold the pieces against each other during baking (poly. stuffing, piles of fine grains, etc.)
....use an armature as well as the "glue" (such as a piece of toothpick, bit of wire, or bit of cardstock, etc.)
... just rubbing Diluent on the baked clay makes it become tacky in a few minutes and enhances the bond between the raw and baked clay which may be enough to hold them together until the heat activates the normal bonding
..........that bond will be even greater if the pieces are allowed it to sit overnight

........can also try rubbing the surfaces with Mix Quick or another soft clay, or Vaseline, then let sit.
...use the same method as for an earth clay ...first score the attachment surface, and then treat with diluent or use a thin film of liquid clay. Katherine Dewey
...or you can simply let the bare pieces sit together a day or two before baking it to give the clay a chance to adhere well... it should work no matter if you do that or not, but I like to leave it so the new clay has a chance to kind of leach some plasticiser into the baked clay and create a stronger hold.

While baking, you can also use a pillar of poster tack to hold up an arm or press two parts together (it's that sticky, non-oily stuff that you can stick things onto the wall with ...you see it at the check out counters a lot in kmart, target, etc. my current package is called Fun Tak by Dap ...or Blue Tac from a hardware store).
.... you can also rebake the stuff, reshape it, rebake it ....it does not slump ....wonderful stuff..Cecilia in SD

If you have a droopable item, don’t remove the propping until the item is completely cooled. . . the polymer will be somewhat soft and flexible when removed from the oven and won’t attain its normal hardness and stiffness until it's cool

clay can develop cracks (large or small) while baking, or cooling
...this is especially true for rebaking in certain situations, but there are other reasons too
(see Heads > Cracking for a full discussion of reasons, and baking techniques to avoid cracks)

For seated figures or those in unusual positions, or for things with unusual shapes, it may be necessary to use wood blocks or crumpled aluminum foil (covered with batting or wadded fabric, etc) as supports to keep them from changing position during baking.

(for sculpting, support, and baking stands for figures, see Sculpting-Body > Tools > Support Stands)

Katie's lesson on baking a standing. figure
... to make sure the feet are really flat and the weight of the sculpt is balanced well over the feet (& because that can change slightly when the clay softens during baking), she
firsts partially cures just the feet of a med-small sculpt by heating it with a heat gun or hair drying while it's standing on a ceramic plate or sheet of glass (not in oven)
...after cooling, she hangs it in the oven from an oven rack (by an "armature wire" she's left sticking out of the top of the head) with its feet on a plate and bakes it for 8 min in standing position
..lays it down on a cloud of fiberfill (with a bit of fiberfill over the projecting hands and feet), then bakes for an additional 15 min+... cools in oven
http://tutorials.theclaystore.com/techniques/firing-a-standing-polymer-clay-doll

DARKENING, scorching and BURNING

Polymer clay will begin to actually burn at temps over 390 °. . . this should be avoided at all costs. ....Thick smoke, a *terrible* smell, and burned, bubbly polymer items will let you know you forgot to double-check the temp on your oven, or your toddler was fiddling with the dials while it baked.
. . .if this happens, ventilate room thoroughly and quickly and leave the area (take pets too) ....see Safety page for more info

NOTE: it is possible that the clays reformulated with new plasticisers in the EU in 2007 (Fimos, Cernit) will have a slightly lower burning temp than the other polymer clays, but have no idea

Clays will run the gamut from darkening to scorching at temps between 225-275 and 390 °.
....
.. darkening or "ambering" of certain clay colors occurs because side reactions, such as oxidation of the pigments and other materials, will be caused at higher and higher temps

Baking time and temperature are interdependent and a trade-off, so for the least darkening, one may want to bake at a slightly lower temp, but for longer (see equation just below):
...for
thermosetting plastics such as polymer clay, the "best" curing temperature is just one at which it polymerizes at a reasonable rate
.....the hotter the temperature, the quicker the setting reaction will happen, but the reaction will still happen even at somewhat-lower temperatures -- just takes longer to finish
....(the DH says there's a rule for that ratio:."for every 10 degree C (18 F) loss in temperature, a reaction will proceed half as fast -- or in reverse, for every 10° C or 18° increase, the polymerization rate will double" ...exponential change
(more about this below in Controversies)

The amount of translucent that's in (a brand's) clay base has a LOT to do with whether it'll darken when baking. . . .
. . colors within a brand may have more or less translucent in them --some colors have a lot, and they darken more when baking. Some colors have white in the base which opaques the color more. You can tell pretty easily, once you know what you are looking for. . . .
..... flesh colors are particularly bad this way...they have a mostly translucent base
..... some of the Fimo colors like purple and magenta too . Sarajane H. (also one of the dark blues)
..... with Premo, the discoloration seems to happen with translucent, white and the pearl colors when they're cured too long (a few minutes at 325º doesn't hurt them though, which I've done when using liquid clay). Elizabeth
.... Sculpey III colors contain a lot of translucent.... like the old Yellow
......also most lighter colors of Sculpey III (as well as original white Sculpey will darken, or turn purplish, or scorch at those temps ...the manufacturer recommends using a temp of 212 for pieces that are made up totally of those colors (interpolate to a higher temp if mixing with other colors, or possibly use the "enclosed" method below). (This used to be true of Fimo’s translucent too, but their new formula is fine at 275.)
.....SuperSculpey baked at a slightly higher temp, just under 300 °, will darken (but it also makes the clay fairly strong). Katherine Dewey (so especially good if you will be using the SS as an armature and covering it, or painting it)

....Kato Polyclay darkens less than any other brand, and can also take higher temps for regular baking (up to 325).

(to test for translucency of a particular clay, put a small flattened piece of the clays in question on a sheet of glass or acrylic, then shine a flashlight up through the clays in a dark closet)

techniques for.... PREVENTING darkening

SUMMARY... insulating and/or enclosing a baking item will help moderate the heat --esp. from hot spots or temp. spikes-- and prevent darkening:
...use a container like an aluminum foil-covered roasting pan, or roasting bag, etc.

...enclose the item under a thick layer of cornstarch (or other fine oven-safe powder)

Certain colors (and brands) tend to scorch at lower temps than others, and longer baking times (even at lower temps) can also affect those more than most other clays
......all? translucent clays .... (except Kato's??)
..... Sculpey's bulk white clay (comes in a 2-lb box)... SuperSculpey (flesh-colored, in box)... and Sculpey III's lighter colors (in packages) to a lesser extent
.
..
other clay brands can be affected but not nearly as easily
....the exception seems to be Kato Polyclay whose colors stay true, even at temps up to and past 300 °

Certain baking situations can also make this happen more easily:
........ clay which is somewhat close to the coils (usually in a toaster oven), or directly on a metal or tile surface (which can heat to higher than the ambient temp)
........clay which is too close to an oven wall, or in a hot spot of any oven
........clay which is thin or extending from the item is also more vulnerable
........higher temps... and for some clays, longer baking times

TESTING the TEMP:
...First make sure that your oven is heating to the correct temp by using a thermometer
.... If you have trouble with areas on the clay darkening, also make sure the oven doesn't have hot spots
...be sure to put your thermometer reasonably close to the clay (rather than off to one side of the oven), because in the oven may not register on the thermometer otherwise.

PARTIALLY covering

DRAPING or LIGHTLY COVERING:
...I have found that placing a damp paper towel over my items prevents them from scorching. Sue A.
... this technique also helps to protect smaller or thiner or extending components of an unbaked sculpture
......wrap or drape damp paper towels also just on any pre-baked parts.
... I'm partial to (clothlike) Viva paper towels as they have almost no texture (soft & clothlike), and they're durable, good for multiple use. Katherine (Dewey?)
(It isn't okay to get moisture into clay, but just a bit on top of it while baking seems to be fine.)

a bit of polyester fiberfill can also be used to lightly cover any projecting and/or thin parts of a piece during baking
...... e.g., Katie's photo of the hands of a figure covered with fiberfill:
http://tutorials.theclaystore.com/techniques/firing-a-standing-polymer-clay-doll --last photo)

I don't have issues with my clay getting darker anymore using this method:
...I use a glass baking dish, then cover the bottom with polyfill
...I make an aluminum foil gate around my sculpt in the baking dish, then drape a wet dishtowel over foil & clay
...I cook all my various size dolls for 40+ minutes, but I use Prosculpt polymer clay. GardensOfUtopia

TENTING:
....
You can tent your baking items with a sheet of aluminum foil, especially if you use a lot of white, translucent or pearl colors in your mixes. ...check it at half an hour, and then every ten minutes.
........caution though... any place that the aluminum foil (or anything else very smooth) touches the clay while it's baking or cooling, will cause it to take on the same texture, causing shiney spots
....
tenting with a piece of manilla folder over the top of the tall part (of the egg) keeps the top of the egg from browning, and I make sure the folder is at least 1" away from the upper heating element.....at first I was concerned about fire hazard, but now I've use the method hundreds of times without smoke or flames! LynnDel
....since I've started shielding all the pieces with tin foil during baking, my white clay (actually 50:50 white: fimo pearl) stays white. Alan

summary of more ways

ENCLOSING in a CONTAINER (completely enclosing)
(....see
below in Enclosed Baking for loads of info on using boxes, roasting pans, roasting bags, etc., to bake in or to place over the clay)

ENCLOSING in CORNSTARCH and other fine powders
.......I placed a tin filled with cornstarch on the tray. I place the clay project into the cornstarch, making sure the bottom and "empty spaces" are well supported by, and the top is covered with at least a 1/2" of cornstarch. . . using this method, I have NEVER burned/discolured a project ...I either leave the project in the oven to cool down. Peggy
(see more powders and more info on using them this way, above in "Support and Propping")

COATING with POWDERS (metallic or chalk) (permanently , or temp?)
metallic powders seem to be unburnable... (chalk powders are pretty impervious too)
.... so it might be a good idea to coat your white/Pearl item (or area) with white powder (metallic or chalk)
before curing and softly brush off excess (you could also brush it off after baking as long as you are not using a convection oven). faun
... I put the Pearl colored Peal Ex powder on my Santa beards with a brush and baked, then I'll glaze with a satin finish ....they came out nice and white, and I baked at 275 for an hour. deb jean
...would a coating of cornstarch work too as a temporary protector, rinsed off after baking

ENCLOSING certain PARTS
.....
I wrap any highly-placed parts or any thin, prebaked of a sculpture with cotton batting, which I then secure with aluminum foil
..........I do this after the first 20-30 minutes of baking time....... works for me, Katherine Dewey
.....would wrapping with plain cotton (balls) or polyester fiberfill work as well?
... otherwise maybe just strip of cotton fabric?

ELEVATING.... In a toaster oven particularly, it's important to use a block of wood or scrunched logs of alum. foil, etc., to elevate the bottom of the baking pan farther away from the lower coils... my toaster oven gets hotter on the bottom than on the top unless I do this... then baking works well, especially for items that are likely to darken. Diane B.
....certain baking materials like metal or ceramic tile, will also absorb more heat, so elevating can help there too
....can also elevate an item farther from the bottom coils by placing it
on a cloud of polyester stuffing or batting (which is on a pan or cardboard, etc.)
...I line the bottom of my aluminium pan with several layers of parchment paper(or paper, paper towels,etc) ... when one layer gets worn or soiled, I can just lift it our and another one is ready to go. Kathy

HEAT SINKS ....can use tiles or other things in the bottom of an oven for evening out the temp in the whole oven chamber
(...see all info on this below in "Heat Sinks ")

I had one particular non-stick baking pan (a gray one- brand new from the grocery store) that burnt everything i baked on it. Needless to say I didnt use it long.

color changes
....With your discolored pieces, were you by any chance using a mold and a mold release like Armor- all ? I tried Armor-all a long time ago and had weird color changes when using Cernit clays.
. . . I do know that if I use a lot of Diluent-softener with some clays, it changes the color during curing...usually an all-over even color change (...the flesh might get an orangey or yellow tone). Jeanne R.

completely. "ENCLOSED" baking method

(for safety....avoiding baking smells... and avoiding possibility of darkening/scorching)

These methods require baking a bit longer because it will take a time for the heat to penetrate the enclosure (longer for denser materials) and get the air inside the enclosure up to the proper temp.

Baking in a completely enclosed unit does several good things:
....inside the enclosure, the heat is evened out so that there are no hot spots
... it also keeps lighter pieces and projecting or thin areas from from browning or darkening, and keeps items protected from oven hot spots or coils, etc
...it keeps the plasticizer which is emitted from the clay over time from collecting on the oven walls
...and it also blocks the normal odor of baking clay from getting into the air
........however, to avoid the odor completely, let the whole thing cool down before opening....
or open it outdoors and move away from it (BarbaraJ.)... or hold your breath!

Baking in an airtight aluminum foil roasting pan is working!
..... I just use a cheapo disposible aluminum roasting pan, and heavy duty aluminum foil (over the top to seal it). I can get lots of stuff inside.
.......No ill effects on my projects, and no odor while cooking ....I let it all cool down before removing the foil.
.......Could stack racks inside too. Donna Kato.
...or use two roasting pans, and invert one over the other, clipping together their rims with metal clips
...Since the bottom of a disposable pan is not perfectly flat, you can put a tile or two, block of wood, etc., in the roaster, and place your items on top (or add some fiberfill or paper, etc. first)
.....Seth's method for baking at 290 ° in an aluminum roaster, with two 6" tiles on the bottom (may work at this temp. only if using Kato clay or a mix with Kato?...and no Sculpey or translucent)
http://www.polymerclaycentral.com/cyclopedia/baking_equipment.html

I have used two large cookie tins like the ones Christmas cookies in for at least the past 2 yrs. (These held 2-3 pounds of cookies each... one is square and the other is round).... they have tight fitting lids
...I line the bottoms with a layer of polyester polyfill and I have never burned anything in them --even translucent clay doesn't burn.
...I take them out of the oven after the required time and let them cool before removing the lid (if you remove the lid before they are cool, you do get some fumes). Flo

I use a deep steel bowl turned over the piece. Jody B.
... could also use a cardboard box with one side cut away, inverted over the item (on a baking tray or aluminum foil, etc ).

I put my items completely inside a cardboard box with lid on, which has been lined inside with aluminum foil
...the clay bakes fine, and eventually the aluminum gets kind of greasy or oily, which tells me that at least _some_ plasticizer is getting trapped in there, and not going on my oven walls. Beth

You can also use a sheet of glass from a photo frame as a tray (with sheet of paper on top of it if don't want shiny spot)
...then attach a dome of aluminum foil over it.
...if you want a lip to help hold the aluminum foil, you can create one around the edges of the glass with clay. DB

I swaddled my pieces in a cocoon of aluminum foil and fiberfill ... no more darkened clay! I tried it with my little angel which went through 3 bakings! Genevieve

roasting bags for turkeys, etc.
....I just tried the "Look" baking bags for turkeys
.......on the bottom of the inside of the large bag I place a glass baking sheet
..........then I place another baking sheet under the bag since the bag should not come in direct contact with grill or sides of oven
......... I place my items in the bag (on paper or fiberfill, etc.), fold the ends over, and clip shut with metal clips... no fuss no muss
.......no smell of baking clay ...and you can see through to make sure nothing has tipped over
.......the bag will rest on the items when you put it in the oven, but then it slowly puffs up fully with air (if the bag stayed on the clay, it would cause a shiny spot)
.....
.... the medium size bag (10x15) with an 8x11" pan puffed up at least 3" ...the large bags (18x22) puffed up 6"+

...they come 4 bags to a box in the medium size (10x15") which fits a 1 qt baking dish perfectly
.....the large turkey bags come 2 to a box and take a large size pan.... I can fit in a 14x14" glass sheet inside for baking switchplates.
....to bake a tall item, put in the bag lengthwise and clip the bottom shut
... I've re-used my bags over and over about 20 times till I accidentally rip one (can tell if the seal is still good by whether the bag puffs)
…You can see a film inside the bag after a few uses, and the odor when you open is awful ( if you forget to hold your breath, take outside, or let cool first ) CherylAmie



ALSO, electric roasters and electric frying skillets and even crockpots are also completely enclosed, so they should also work
... see below in "Other Ways to Cure for much more on baking in those

if I open the enclosure immediately, then yes, it emits a strong smell. It even causes a mild nausea with me.
......so what I do now is to leave the pan covered for some hours or overnight in the oven itself and somehow the smell dissipates.... or else I open the foil (outside), and move away. Barbara J.

"HEAT SINKS" to even out the oven temp ....(tiles, etc.)
(not to bake on)

(for making shiny clay sheets from baking between two shiny tiles, see below in "Using Tiles for Shiny Finish")
(for using tiles in other ways when baking, see above in "Baking Materials" and also in "Using Tiles to Steady the Temp.")

It's good to use tiles or other materials in the bottom of a toaster oven to even out the temp in the whole oven, to avoid hot spots, etc., creating a "heat sink" which is sort of like a heat sponge. . .when you turn on the oven, the heat sink will soak up most of the heat.
......b
y their placement, they also 'direct' the heat flow to the their edges.
...(Once the thermostat says that the oven is hot enough, it turns off the heating element. The oven starts to cool. Now the heat sink will start emitting some of the 'captured' heat. The end result is a steadier cooking temperature.) Lysle

(using a heat sink) has also reduced our electric bill a tad because the oven isn't kicking on as much! sunni

In my convection oven, I placed some standard sized tiles under the rack in the broiler pan
...I had pre-measured my width and length, and found a couple of tiles that would fit (no cutting necessary). Patty B.

I was concerned about blocking air flow with two 6" tiles.... I found a sheet of smaller tiles connected together by some dot of adhesive, and the space in between all the tiles allows the air to flow!! (and should heat up more quickly?)
........It was easy to cut off some of the tiles so I could get an exact fit over the oven rack. Perfect.
....Now the temp does NOT spike and remains very consistant once I reheat the oven. Ilene

A ceramic tile will heat evenly and maintain an even temperature across its surface for a longer period of time.. like a pizza stone does. Therefore the fluctuations in the oven temperature will not affect the baked item as much. This is a technique used in fusing glass, but applies to using any oven/ kiln. . . also, if an item is resting on the tile, then it should bake evenly. bastet (...but ceramic tiles heat hotter than ambient air, right?)
...I used ordinary white tiles from Home Depot/Lowes, and covered the entire baking rack because I only have one shelf. Trish
...I keep ceramic tiles in the tray that's provided, since my bottom elements are not covered. Bean

I use a pizza stone... and just keep it in my large oven all the time.

I will be placing broken bits from terra cotta bowls (the kind that go under the flower pots) in the floor of the oven to help minimize the fluctuation of the temperature. . . . I also bake my items on a ceramic tile I picked up for free by asking the local Paint and Tile store for discontinued brands. Sunni
...with my conventional and toaster ovens, i have red bricks in the bottom of both (chunks in the toaster oven), plus i have a terra cotta slab on the lower rack of my conventional oven. in the toaster oven, i have a dedicated ceramic tile on the rack. these absorb and reflect the heat from the oven reducing the fluctuations, stretching out the time between the (usual temperature) spike and the drop. i've found it so effective i leave them in the conventional oven for regular baking. sunni

...you can use red brick, terra cotta pots or pot shards, cement stepping stones or rocks.
...... i find the red brick and terra cotta to be the most effective, but all the others do just fine! sunni

(my clever hubby suggested this one day and it really evens out the heat in my cheap-o toaster oven)
......now I rarely burn anything...even paper-thin pieces... even the much maligned Sculpey
...lava rocks. Yep...garden lava rocks.. I completely fill the bottom of my toaster, under they rack, and pre-heat for a few minutes longer to heat the rocks fully... once my thermometer hits my target temp....it stays there. Lylyfai

make a block of plaster to act as your heat regulator ....it should come within 1/2" of the edges of the oven. . . it's function is to help distribute the heat evenly.
......I also have two of them and keep the second one on top of the oven. When I am done baking the first item and need to put something else in the oven, I switch the blocks.

lesson for a sheet of well dried plaster:
--Line the pan with aluminum and then fill it up with plaster.
--Let the plaster cure and dry for a few days.
--Then bake the plaster in stages starting at 150 ° for 5 minutes and raise the temparature 25 ° and bake some more till you finish baking at300 °. This will drive out the moisture. Do NOT try to remove the foil if it doesn't want to come off. This sheet of plaster is soft and brakable.)
(--Now each time you are ready to clay warm up the sheet of plaster to 265 °.) Lysle

Or see if you can get a sheet of steel about 1/8" thick to use as a heat sink. . . Lysle

I use an aluminum roasting tray with couple tiles in its bottom ....then another tile to cover it...sometimes I clamp down the edges, sometimes the object is too large. Dar
... see also Enclosed Baking Method above

PREHEATING time will be longer with these methods because the heat sinks will take longer to get to the proper temperature than the air will.
....The thicker the items, the longer it may take.

Leigh from PCC says that it took a half hour for the tiles to reach 275 ° (she's done some testing with a remote thermometer and found that her (convection) oven temperatures jump all over the place, unless she used tile to steady the temp -- then they varied only + or - 10 °).
....
I add 20 minutes baking time to allow the tiles to fully heat up and penetrate the clay sheets. Sue

What I do to heat up my tiles prior to baking (so as not to have to add too much additional time in the toaster oven), is to always put two "ready to bake" filled tiles on top of my toaster oven while another one is baking... then when a "cooked" one is taken out, a waiting one is hot enough that I have to pick it up with my pliers. Sue

Also, in a toaster oven it's particularly important to use tiles, or at least to use one tile or block of wood just to elevate the bottom of the baking pan farther away from the lower coils... my toaster oven gets hotter on the bottom than on the top unless I do this... then it works well, especially for items that are likely to darken. Diane B.

baking TALLER pieces

About turning a toaster oven on it's end (its short side). If the oven is placed on a heat safe area (must be able to withstand 212 °) you will have no troubles. Unless of course it needs the crumbs cleaned out. (there is a little door on the bottom that can be opened to clean it. If the oven is cold you can vacuum it out.) If you have a simple one, No fancy digital clocks, etc., and are not planning on using it for three days, You can actually unplug the thing and totally immerse it in water. Then stand it on end to let it dry for 24 hours. Do NOT try to use a blow dryer to dry it out. Lysle
...Convection ovens can be turned on their sides to bake taller items. Just be sure to turn the oven so the control knobs are on the bottom, not the top. I bake 12" tall lamps in my Welbilt this way and it works great! Linda

get an old oven and set it up on a covered porch or place a waterproof cover over it when not in use. Those who bake really big pieces regularly should invest in one. . . On most used stoves it's the burners on top that are the cause of their replacment. Second cause is bad heat controls for the top. The first Oven specific is the temrature control. That is a replaceable item. Not necessarlly a 5 minute job but doable…Lysle?

see also Katie's lesson on baking a tallish sculpt in steps... first step outside oven with heat gun to set some parts, second hanging/standing in oven, and lastly lying down (above in Propping)
...see also info about baking a tallish item in a roasting bag, above in Enclosed Baking

About the darkening of the Sculpey translucent and light colors at the temp. listed on the package, 265 or 275, to keep this from happening, try any or all of these things:

some remedies .... for already-burned items

A friend of mine said she soaked some white beads that she burnt in a bleach solution. She said it took the brown out. Denise

Thanks to Cindy, Jeannine and Susan for advice on my scorched fairy....my little figure was saved from the trash bin and I love the way it turned out
... . I mixed the silver and gold Pearl-ex together before adding Future (to them). (Mixing the two powder colors together seemed to take away some of the brassy look of the gold.) Mary
...It was a new oven so I wasn't as used to it , and of course her pieces burnt.... on the ear, face and arm.... It was just wonderful to see how creative and resilient she was.. she covered the burnt spots with metallic paint and it just made the cutest character. Her elf now looks like a little green martian!! Kathy D.

We did several things with our burned things:
. . . My granddaughter applied some Rub 'N Buff to some of them . . . and some Lumiere paints to others.
. . . I mixed some Pearl Ex into some Varathane and painted that on. .
. . .We also left some of the blackest ones plain ...but sanded, buffed and varnished.
(we had accidentally burned our turquoise nugget beads {see Faux-Turquoise} ).
... however, now we have some fair looking "onyx " and some other interesing looking metallics... Virginia in PA

They could also be "antiqued" in the crevices with a light color of paint

DON'T THROW IT OUT ....cover or embellish it with paint!
...wipe the baked clay down with rubbing alcohol first, then paint.
...if you like Raku, e.g., try Micaceous Iron Oxide, let dry, & THEN put on Pearl-Ex colors (esp the blues or greens.. like in real raku)... if you get too much of the PE, apply more paint... actually you want several layers of paint to start with... THEN do the PE... after that, seal it (Futuret works super). Patsy M.

I would suggest covering with a thin layer of clay (use a thin coating of liquid clay first)... decorate, and re-bake. Patty B.

I made a bunch of faces for my fairies. When they came out of the oven, they looked marbled, with parts of them almost brown, like wood. Maybe I'll call them my 'wood' nymphs. ....One came out just looking psychotic! Sue

I forgot some faux pink granite beads in the oven, and they burned to a crisp..... bubbled, burned football beads (looked like lava rock).
...So, I took the bench grinder outside, donned a dust mask, and smoothed one back into shape with the grinding wheel... underneath the char was some beautifully browned translucent with copper Luminere reflecting through! Gorgeous! Denise M.

Marie Segal knows a fella who makes (translucent) toads and burns them on purpose, to raise little warty blisters all over their little toady bodies. Katherine
..."critter" heads burned-darkened (not for the easily offended): http://www.norajean.com/MSAT/ClayArt/Swaps/Chimbo.htm

Someone reported that overbaking SuperSculpey, then buffing it yielded a beautiful color though

my oven got set to 400 somehow, and my Celtic knot barrette had puffed to over twice its starting diameter ...when cooled, had quite a grain .... wood - bark-ish. Seanette

baked or toasted clay can also be ground up or broken up to use as powders or gratings (for inclusions, surface effects) or to use as tiles for mosaics, inlays, onlays, etc.
(for more on grinding or grating baked clay, see Cutters? or Inclusions?)

MULTIPLE bakes & PARTIAL baking

Polymer clay can be baked multiple times and the clay won't be damaged.
....(some people insist that the first bake should be a complete bake; others disagree--see below)

Partial baking can be used for small areas or layers or surface embellishments of clay sculpts before additional work is done
...this is usually done by wafting over with a heat gun
.....to test the temp of any heat gun at a particular distance, Kathleen Dustin says to aim it at an oven thermometer (which is sitting on something heat proof!) for some seconds, and then read the resulting temp until you find the best distance for 275 or 300 degrees, or whatever you need. ... also always wave the gun back and forth when curing rather than holding steadily on one spot.
...Bunny's lesson & explanation on using an embossing heat gun (to cure fingers of a sculpture to a certain shape, in this case)
......she waves over the area from 6-7" away, for 1 -2 minutes ...then to check if it's heated enough, she sees if it will move, or if her fingers will leave fingerprint impressions = not cured enough http://www.thewildbunny.com/HeatGun.htm (gone)
...polymerclayfan's lesson on partial baking as he works http://www.polymerclayfan.com/partial-baking.htm
May need to protect other areas from the nearby heat though while using a heat gun--with aluminum foil or cotton cloth or a physical barrier held in the other hand, etc.
...this prevents any "finished" areas from getting fingerprints or distortions by further handling while working on other parts of the sculpt
Follow with a full bake when all areas are finished.
Certain bakes may even be at a higher temperature or shorter durations (for example, to thoroughly cure and clear up liquid clays)

Some of the clays which brown mostly easily may darken with rebakings however... these often have translucent in their makeup, even if they're dark colors (to test for translucency, put a small #1 sheet on a piece of glass or acrylic and shine a flashlight up through the clay in a dark closet
... Kato clay will darken the least in all colors, including white... Sculpey's translucent and lighter colors are the worst.
When trying to avoid darkening, make sure your oven is the correct temp and there are no hot spots, or partially enclose the clay by tenting with aluminum foil, or draping with damp paper towel, etc... or best, use a totally enclosed baking method
(...see all those techniques above in Darkening).

Some people feel the first bake should be a full one (if the bulk of the work is done at that point), and subsequent bakes can be shorter just to set the clay to firmness or to completely bake through thinner layers (10 min or so).
...but others feel that a partial first bake is never a good idea and some feel it could be a problem in certain situations, especially if one is selling items or otherwise need to be absolutely sure nothing will ever occur from having done this:
......In my opinion, with only partial baking, the clay will not reach the full temperature on the inside and now the movement of the pvc particles is hampered because the outer shell of the clay has hardened but the plasticizer can no longer migrate to the surface and the particles can't bond together. Patty B.
......(I disagree)...If you partially bake a piece of polymer and then cool it and then rebake it for additional time the Polymer will Polymerize completely. . . .
The action of Polymerization in not the same as that of cake levening. In a cake there can be up to 3 actions that create leavening,
1) expansion of air bubbles caught in the network of protein chains of the flour and eggs. 2) the first action of double acting baking powder when it is mixed with a liquid or the action of baking soda mixing with an acid. ( The release of CO2 gas) ( yeast does this as well in breads and some cakes) OR 3), The 2nd action of double acting baking powder when it is heated which is to release more CO2 gas. The 2nd 2 reactions are limited and will not work after a certain time. point of fact is that a sponge or angle food cake that are made with no BP or BS and use lighter forms of Protein such as egg whites or cornstarch will continue to rise if baked to a certain point and then cooled and rebake. ( although it is rare)
The action that caused Polymer Clay to polymerize has to do with the evaporation of the plastisicer and the proximity (propensity?) of molecules of PVC to form long chain bonds. ...This action will continue if stopped if there are enough free molecules of PVC available and there is sufficient energy to cause the bonds. In other words if you rebake a piece of partially baked Polymer clay and the unbaked portion reaches the needed temp. ( aprox 265°F for aprox 20 Min), you will polymerize all the PVC. . . . After all of the PVC has polymerized, additional baking will not do much more. And that is today's polymer chemistry lesson. There will be a test tomorrow. SL SAVARICK

clay can develop cracks (large or small) while baking, re-baking, or cooling (so increase and decrease temperatures slowly)
...this is especially true when
a dry-ish clay layer is overlying a juicier one (or vice-versa) ....or when a thin, raw layer is overlying an already-cured thick layer, but there are other reasons too
(see Heads > Cracking for a full discussion of reasons, and baking techniques to avoid cracks)

(liquid clays) . . . these products can be heat set with an embossing heat gun. . . . First of all, the application is usually a thin layer applied to a clay body which can support it. Secondly, it is being used in a decorative manner, the clay body will provide the support and strength. So, yes, you can heat set TLS and then apply more and then bake the clay as you normally would. Patty B.

(see also below in Other Ways to Cure for using a heat gun to totally cure the clay)

Jeffrey Dever's hollow forms (mini & larger) which could be knobs or beads uses layering and multiple bakings, with found, altered, and custom built forms

(see Vessels) ....DB: Add more

ICE WATER PLUNGE ("quenching") ... for shine

(see much more on this in Translucents > Quenching/Ice Water Dunk)

~ think Lynda Struble (a plastics chemist and a polyclay sculptor) was the first person to advocate the ice water plunge for stronger clay. Sue Heaser published an article about what Lynda said in the 1998 British Guild newsletter, and clayers all over UK have been using it ever since.…

(The ice water plunge also results in a clearer translucent clay. . . some people have said refrigerating or freezing canes with translucent in them will make translucents clearer too. DB)

I learned from bitter experience that when you give cured clay an icewater bath, you really need to let it return to room temp before trying to flex it at all. I broke a cuff bracelet that way. Suzanne

BRIEF HIGH HEAT ...for shine

 

using TILES for a SHINY finish

(for using tiles in other ways when baking, see above in "Baking Materials" and also in "Using Tiles to Steady the Temp.")

(for creating small tiles, see Cutters-Blades)

PöRRö's shiny flat surfaces from baking between two shiny tiles
http://members.surfeu.fi/porro/eninti.htm (see more at her page on this method)
(....relates also to: finishes, faux's, pendants, beads, tiles/mosaics, baking, translucent categories)

I love the little glass (shapes) i bought at Michaels.. for a window hanging or suncatcher i believe...but I bought a small or 5" hexagon shape piece of glass...I use it mostly for TLS projects or a piece that i want a very glassy glossy touch to. Whichever side touches the glass whilst baking is the shiniest...of course in retrospect wish i had bought 4or 5. Donna AB

Well, I have been experimenting this for almost three months …I have few quick tips to people who want to make beads or flat pedants with this technique:
1) Select your tiles carefully. Use light and see if the surface is really as flat as you think. Most of the tiles have round edges or some faults. Mark perfect tiles with pen if you have a lot of tiles :-)
2) Only the surfaces that touch the tile will be glass-like. If you make a ball and then flatten it in top of the tile and put another tile to top that you will get flat object that has matt sides and shiny faces.
3) Before making anything clean your tiles. Any grease or dust will definitely show in your work.
4a) Basic thin pedants: make a sausage (cane, marbling, what ever) and cut about 1/2 " slice of it. Put it on the tile and then pierce the hole straight. Leave a lot of space between other pedants / beads, they get larger when pushed. After making all, take another tile and put it _straight_ to top the first one. Push gently but firmly until the space between two tiles is suitable. With pedants this is about 1/4 " or little less.
4b) Basic beads: make a sausage and cut about 2/3 " slice of it. Take a pin or cocktail stick (toothpick) and pierce the bead from the middle. Leave the stick with it. Now put the round face side to tile and gently rub and push with your fingers to flatten this bead a little bit. Continue as before. Suitable space between tiles is about 2/3 ".
5) Baking: Put some heavy glass objects or some other tiles on top of the tiles. You need to put some weight to ensure that the top tile is really touching the beads. Use normal temperature but reduce (increase?) the time with additional 20 minutes. Put objects in warm (preheated) oven (better results with surface! ). After time has passed take the tiles out (watch, they are really hot and have a lot of water in them !) and let them rest for about 10 minutes. Then remove the beads; cold water is the best way to take them out. Dry the beads and now --if you prefer to let things cool in the oven you may put them back and do that (They still are warm / hot). If you want to cool them in room temperature, take off the sticks (if you have them) and let them cool.
6) Some notes: What was inside of the cane is now in the border of the face. You get a bullseye effect with this one if you have only thin sheet of one color around different colored log.
7) Using colors: Try metallic or pearl ones. Basic colors, especially white, tend to seem "dull". If using strong colors remember that they darken a lot in the oven. In these it shows more than in normal canework. Mix more white to your colors than usual. PöRRö

OTHER WAYS to cure polymer clay
(or stabilize with partial curing)

Various things besides traditional ovens can apparently be used to completely cure polymer items, or to partially cure them.
.....partial curing of clay or other materials (like paints, liquid clays, etc.) can be helpful to set them a bit before fully baking, or make them travel-worthy, or to set certain areas while sculpting/etc. to avoid distortion while continuing
....complete curing can be difficult for certain items or areas as well... for example, when inlaying clay into large items like bowls, stairways, etc.

Some of these qualify as "completely enclosed" baking methods, with all the benefits those create (see Enclosed Baking above).

Some of these may also work well for travelling (in the car or in motel rooms)
.......with those gadgets that fit into a car's cigarette lighter hole and accept a regular AC plug at the other end, a crockpot might be good for baking clay long car trips too. Diane B.
... or for dorms where no coils are allowed?
...or just when extra "ovens" needed

electric roaster ......(looks like a crockpot/slow cooker, but not often round).
...the heat ranges from 150° to 450° F (temp. dial on front)
...the Nesco brand offers various sizes --4 qt (smallish-crockpot size) to 18 qt... (one 12 qt model is convection)
http://www.nesco.com/products/?category=700
...... interior "container" of Nesco roasters may be steel, ceramic, or non-stick
... with roasters, the heating elements are all enclosed within the walls of the oven (like a crockpot) so no scorch spots! I don't even tent anything anymore
.........I keep an oven thermometer inside all the time, and whenever I lift the lid, the thermometer is always at 275. (In my toaster oven, the temperature spiked lots of times! It was so hard to get it "just right"..).
.... (my convection roaster?) is also smaller than a convection oven, but has almost the same size baking cavity...the lid had a glass panel that i can peek into (i keep the oven thermometer right below the glass panel... heh-heh..)
... i like the side handles that are on my roaster too
...preheating... It takes about 15 min. to reach 275 ° when I turn it on (about 5-7 minutes longer than a convection oven) AND, it's only half the price! )
... I've only been using this roaster for a couple weeks... the beads that I've baked are very strong--i couldn't break them (1/4" thick cane slice).
... i would think it is a must to use the metal rack that comes with it to lift things off the bottom... I have a regular cookie sheet on top of the rack that i bake on... i use folded index cards to place my work on the pan - and i pick it up when baking is done by the folded up edges of the cards... \______/ (crude ascii portrayal of index card side view). Stargazer
...i use a (small?) roaster oven, that way it's closer to my work area than the kitchen oven, etc and it keeps its heat better than a toaster oven, and i just sit it on my tabletop... and it's also cheaper to run than other electric ovens. ...it's a good way to heat beads for drizzling on liquid clays... twiggy
...the one I got at Target has approximate interior dimensions: 16.5"L x 10.5"W x 5.75"H .. $49.99 on sale (even cheaper sometimes)

I have had good results baking clay in an old (very old!) electric frying skillet. Heat it up, place clay on a (metal?) grid inside, cover and bake.... All fumes kept inside - works a treat. I calibrated it with an oven thermometer to find the right temp (very low).
...... It's good for travelling with and an extra to my toaster oven in workshops. Sue
...I have been a skillet curer from the word go. I got a used one from a church rummage sale for a buck,... fiddled around with an oven thermometer to make sure it would hold exactly what I wanted it to for a temp, and it does. ...Reason for using a skillet is that I can run it outside (and avoid fumes for the dh)
......Now, I put a big tile in the bottom of the skillet. It is square, and so's the skillet. Then, I may or may not put anything between it and the clay pieces. ...the skillet is about a foot across, so it will hold 4 tiles, or a LOT of aluminum foil or egg carton.
......And it is a chicken cooker, so it is quite deep with a quite high lid, and will hold up to 4" with nothing touching the lid
.
.... I preheat, pop the piece in, preheat again for about 3-4 minutes to get things pretty even...and then set the timer. ...don't know quite how long to cure these blessed angels I've made.
........Each is lying on its back on a square of aluminum foil, propped as needed (around wings and such) with polyester fiberfill, one spot of cornstarch peanuts up the skirts of each (to keep that form intact), and then the foil pulled up around and "pleated" shut.... Janey
...An electric skillet usually has the heating element directly attached to the lower pan, so might get too hot there if in direct contact with clay.... It's designed to heat the pan and the whatever is in immediate contact with its surface, rather than radiate heat or heat the air in the insulated compartment as an oven does. Those would be my concerns, but if it works, then it works! Jason
...She uses this electric skillet outdoors even in the dead of Minnesota winters and it works great for her.
......She also uses polyester batting to insulate the piece from burning since it's so close to the element. Donna in MT

My simple crockpot makes a good, portable oven for any piece that fits inside it.
...I dug out my crock pot (a Hamilton Beach), cranked it up on "low" (it only had two settings), and it heated to 270 ° and stayed there!! It did take an hour and a half to get up to the right temp, but still- success! The perfect oven was already something we had. ...then if we removed the ceramic liner, it went to 300 °-- perfect for liquid polymer. chel
... should always check temp with an oven thermometer anyway, especially because temps for low med high vary a lot between brands and also between older and newer slow cooker models
........ I always remove the inner ceramic pot so that the piece is closer to the heat source. It has the added advantage in that I can watch it directly (through a glass lid?)
...a crock is great, haven't used it in a while for beads, but I can tell you that it does the job!

....Generally, I bake
at lower degree settings than recommended --but for a longer time ... and that works well

We bought a solar (cardboard box) oven for Y2K & earthquakes/disasters. . .you can buy one or make one yourself in any size though, relatively simply... check out this site for details (also has recipes): http://www.kaapeli.fi/~tep/man/manual.html . Diane B.
....My DH actually built me a solar oven this spring and I have used it for baking polymer clay....and, for the most part, it's worked great! On a mostly sunny day, in central Montana, in early May (still somewhat cool weather?), the average temperature got up to about 300 - 325 °. And the temperature remained fairly constant. I probably had to adjust the angle of the oven every 15 minutes or so (only with some models??) to make sure the reflectors were pointed directly toward the sun but it's not difficult to do. And, of course, I used an oven thermometer to check the temp.
.......The only problems I've had were with the wind blowing the whole works over (we're going to build a stand that will stabilize the oven) and with partly cloudy days where the temperature would fluctuate quite a bit--from 300 ° to 225 ° and back to 300, etc. (The temp of the *food* can't go over 212 ° unless all the water is cooked out of it. The oven itself can heat to over 300 °, though. Christine P.) I'm not sure what that fluctuation would do to the clay. And I've read that the temperature can be adjusted depending on how the oven is pointed at the sun but I haven't had much experience with it....! It's really kind of fun to use and experiment with, and it sure beats the heck out of heating up the kitchen when it's 90 ° outside! And from what I've read, they can be built in all shapes and sizes..... Sally
.....charcoal briquettes (in a cardboard box oven)... each briquette generates 40 °..... years ago I baked a large Super Sculpey dragon in a cardboard box oven using 7 charcoal briquettes. As he had a large foil core, the clay was no more than 1/2 inch thick at any one point so baking time was minimal (about an hour). It worked well.
Here's a scout resources website that will give you more information on box ovens and box oven alternatives, including an inventive idea with sticks and heavy duty foil: http://www.macscouter.com/Cooking/BoxOven.html ...Katherine Dewey

someone posted about baking their clay in a metal cookie tin, propped over a camp fire when she went camping. She wouldn't leave her clay behind even on a camping trip!

when we got back in the (closed) car my squash and gourds (polymer) were as hard as a rock. I did bake them when I got home just to be safe, but I doubt if I really needed to. Flo
Has anybody ever put an oven thermometer in the car to see how hot it is really getting? I think I'll put my extra thermometer in my car, though we haven't had our hottest days yet. Jody

The kids and I enjoy claying in the car (on vacation) and the small convection oven fits under the car seat to bake up what we create.
... I have also used the car dashboard to warm/soften clay.

You don't have to live in Phoenix! This can happen here in England - and we are as far north here as the bottom of Hudson Bay. ...We have a south facing house and I have had a lot of problems with teens keeping candles on their window sills (lava flows of wax, yuck) – and polyclay cures happily if left in the same place (with sun) for long enough! Sue

heat guns
....
Kathleen Dustin sets an oven thermometer in front of the heat gun to determine how far away to hold it to heat the piece to the clay curing temp of 275 °. ....an embossing heat gun from Michael's, the rubber stamp section for partially curing liquid sculpey prior to baking …thanks for that tip, Jody!)
........Kathleen Dustin said she used one to cure small add-ons to pieces (I think usually when backfilling a carved line).
........
Bunny's lesson on using a heat gun http://www.polymerclayhaven.com/lessons/heat_gun_lesson.htm
....(see above for controversy over partial baking though)
...
I am a rubberstamper and I use a paint stripper heat gun to emboss and heat anything needing some heat. It is cheaper to buy, and is made to withstand the hot air returning into the nozzle.
......embossing-type heat tools are not made to take this hot air return and often burn out very quickly (if used continuously for a long time... to completely cure) ....technically rubber stamping heat tools should be held on an angle to allow this hot air to escape, but this has proven to be a big pain.
...the difference in price can be substantial.....paint stripper with 2 heat settings at Home Depot costs $10.00- 15.00 Jan/Toronto
.....Jan's right, a paint stripper will work okay. ...but just be careful as some heat up to 1100° F, whereas most craft (embossing) heat guns only go to 600 °.... be careful no matter which way you go. Dotty in C
......(embossing) heat gun prices range from $20 and way up (though a 40% coupon at Michaels can bring the price down)... the cheapest ones work fine. You can see a variety of them at: http://www.rubberd.com/heatgun.htm Dotty in CA
(see more on all heat guns in Tools > Heat Guns)

Garie has a lesson on making 2 versions of an oven with an aluminum foil-covered cardboard box and a heat gun (but not an embossing type because no heat return??) for baking polymer clay
http://www.garieinternational.com.sg/clay/shop/box_oven.htm

Desiree says you can cure polymer clay in hot olive oil by frying it. She says it takes 1-2 minutes for a thin strip to cure.

I'd build a campfire and boil the darn things! ....It gets a little tricky and you gotta play around with it but get the water boiling first!
........you could also keep em on the stick or on a knitting needle..... still good for when I go backpacking!
...(for more on boiling clay at home, see below in "Boiling & Microwave-Boiling" --results in less-darkened clay colors too)
...(could probably also use Garie'
s method of "baking" in a saucepan with plaster, over heat --see "Stovetop 'baking' in a closed saucepan" just below)

I am tempted by the descriptions of the nice gloss that can result (from boiling, then buffing).
....So: has anyone boiled PC in a pressure cooker? This should raise the temperature, and the pressure may help drive the plasticizer from the clay (one function of the heat is to evaporate the volatile plasticizer, and the theory is that boiling water somehow draws out the plasticizer at lower temps... end of chemistry/physics lesson). . . . . Also - you could use a deep pressure cooker/canner to steam cure larger items. The piece could be set on a trivet/stand, and kept above the (shallow) water. A little bit of water would generate a lot of hot, pressured steam, which would (in theory) do as good a job of setting the clay as boiling. Joshua
...the DH guessed it probably would be okay, but water under higher conditions could attack the clay more than simply when boiling....he doesn't really know though.... Diane B.

Stovetop "Baking" in a closed saucepan, with plaster

Garie Sim's 2-step method for curing polymer clay pieces in a sauce pan with a reasonably-tight-lid on a stovetop or other burner, using a layer of plaster covering the pan's bottom as a insulator
(... the clay will be "baked" with dry heat as in an oven)
http://www.garieinternational.com.sg/clay/shop/cooking_technique.htm
(.....also see links at bottom of that page for more photos)

(this technique should also work on any type of burner or fire --gas or electric cooktop, campfire, etc-- as long as the other steps are followed)

(PRELIMINARY steps)

...find a metal sauce pan with reasonably tight-fitting lid
.....could also use cast iron, or enameled cast iron, wok, or pot/pan with non-stick coating?
......a glass lid is best because the thermometer can be seen during curing without removing the lid
......probably best to dedicate this pan to clay use... if you don't have an old one, check out thrift shops or discount stores
....SIZE factors:
.......before selecting a pot, consider the size of items you'll want to cure, the size of your thermometer, and the 3/4" of plaster required
...... the volume of the pot you choose will change the time required for the initial active-heating (step 1)... the wider the pan, the longer it will take to heat up (same for total volume of pan?)
..........EXAMPLES:
..........7.5"dia x 4.5"ht pot will heat to 285 F (140 C) in 20 min ...& to 293 F (145 C) in 30 min
..........5.5"dia x 2.5"ht pot will heat to 285 F (140 C) in 15 min ...& to 330 F (165 C) in 15 min

...mix up some plaster (4:1 with water) --or Ceramofix (art-type plaster... dries harder than reg.plaster) or similar brand
.....pour wet plaster into bottom of pan till the layer is 3/4" deep (this will moderate the temperature coming from the burner underneath)
.....do NOT use a pre-made plaster or ceramic tile, etc., instead of pouring fresh plaster...those will not cover the entire bottom of the sauce pan, so the temperature will rise too high inside the pot and burn the clay
.....allow plaster to set 30 min (in the pan)
.....(plaster will fall out easily after a few uses, if desired)

...place oven thermometer inside pot (to monitor temperature)

...place clay items on plaster (standing, lying, etc.)
........can first add sheet of paper, batting, baking soda, propping materials, etc, if desired
...cover with lid

(step 1)
...place lidded pan over a med-low to low heat (flame or elec.burner)
...heat till the max. temp you want is reached (thermometer best monitored with a glass lid)
.......probably around 15-20 min, or see examples above for approx. times for various size pots
(step 2)
....turn heat off (do not remove lid)
....allow clay to stand in the trapped heat another 15 min (...temp will slowly drop to about 212 F, 100C)
....(??...remove clay, or allow to cool in pan with lid off or on)

Boiling + Microwave-Boiling

BOILING in a MICROWAVE:
Garie Sim shows successfully boiling various brands of polymer clay in a microwave-safe (Tupperware, etc.) bowl of water in a microwave oven
....the clay will not over-cure ....and can be cured repeatedly
....make sure the water level is always completely covering items in the bowl and about 2/3 above the diameter of the clay (30-40% of water will evaporate during the process)
....do not use a ceramic container (produces heat, and any impurity in the container can have a reaction while microwaving)
....do not use a container that's much too large container for the clay inside
....don't bake too many at one time?
....for ( 3/4") 15 mm diameter items, cook 5 min. (on high?)
... for any size 15mm diameter you can set for about 10 minutes
....he used round beads, but says you can microwave-boil certain small shaped items, and larger items as well though there is a limit to the size? --for larger clay work, use a bigger container and set timing to 10min or more.)
...there may be a whitish clay residue coating on some of the clay after microwave-boiling, but it can be polished (buffed) away (...or apply a matte or gloss varnish to get rid of it)...there is no actual color change

http://www.garieinternational.com.sg/clay/shop/microwave.htm
flexibility after baking vs.boil-microwaving Premo clay
http://www.garieinternational.com.sg/clay/shop/comparison.htm
degree of cure & strength: Garie split open the clay after microwave-boiling and found the clay of equal consistency all the way to the center
comparison of all brands of clay after boil-microwaving a long time -20 min--... color, strength, etc.
....plaquing (mooning)... FimoSoft and Cernit may show plaquing when boil-microwaved for 20 min.
http://www.garieinternational.com.sg/clay/shop/twenty.htm
(Garie also has experiments on testing the strength and the porosity of regular baked clays...see Outdoor > Whitish Coating):

BOILING on a STOVETOP:
(the Scandinavians have been boiling polymer clay a lot longer than we Americans have been baking it!). Kelly
This method may work best with miniatures and small-medium beads? ... and things without thin projections?
....I experimented with different brands of clay--Fimo, Premo & Cernit, including translucent & metallics... they all came out fine
....... also the pre-made holes did not distort. Linda J
....I want people to know that the clay colors come out very vibrant using this method
...... particularly the whites --which often have a tendency to become various shades of cream/eggshell/beige when the clay is baked at the prescribed temp/time
....with boiling, they stay white as newfallen snow ... I'm hooked on this method for my beads!
lesson: ...just get an old pot you want to dedicate to this, and put warm water in (a quart or more)
.......dump the beads in the pot (no lid?) ... bring to boil
.......turn the heat down to a *gentle* boil, and let them simmer at least 15 min or longer (I do mine up to an hour)
.......... I just roll them around a minute or two (at the beginning?)
...... I allow them to cool in the water.... then place them on absorbent toweling to dry

I bought a "hot pot" to boil water in.. . . for curing my beads.

(not related to curing:)
It may or may not be advisable to put a glass or ceramic dish which has been covered with decorative baked clay in a microwave oven.
.. there are several variables which would have to be taken into consideration and addressed, so it's probably best to just avoid it.
.....I suspect the biggest hazard doing that could be the possibility of there being trapped water (from a previous washing) inside the clay, or worse between the clay and dish (in that case, the resultant superpressure water vapour could well explode the whole thing). Alan
... or as discussed below in Microwave-Boiling, the clay may itself absorb microwave energy and heat up, thus softening, etc.

"finishes" resulting from boiling

During boiling, the clay will have acquired a coating of whitish substance, so I simply buff it off with a chamois-like cloth
....... you end up a bead with a luster that is usually achieved with sanding and buffing or with Future --the coating seems to actually aid in the buffing (...it may be that the whitish substance is part of the oil of the clay which then becomes a luster upon buffing)
........... I noticed little if any coating or film on my pieces though so could the whitish film possibly be related to your water source? (or type of material your pan was made from, etc.?)
...
If you have regular community (treated) water, there will be a bit of residue left on the outside of the item. Using a towel or denim to buff this off gives a surprising glowing sheen ...not matte, and not glassy. Just very glowing. It's very odd. But it's VERY pretty!
.... if what you're making has a lot of nooks and crannies , it might not be worth the time it takes to get the desired result. Kelly
...Beads that I'd boiled in a hot pot turned out interesting
....they had a kind of matte finish (no buffing?) and were whiter than the ones that I later baked
....... these two finishes (from boiling and baking) actually looked good together--like getting two coordinating beads from the same batch.

For some reason the boiling does something to the outside of the clay item.
...if I bake as usual first, (then) I boil rapidly for 5 min... let "drip dry" (the same thing happens?)

(see also? ...getting shine from brief high heat at end of baking, in Finishes > Other Ways to Get Shine or Sheen)

Controversies + other factors:

rate of polymerization + baking temps & times:
Some people have heard that there needs to be an exact and miniumum temperature to thoroughly cure polymer clay. The DH-physics-person says that there could be some confusion in terminology about that though:
.....in chemistry, a "melting" temperature is "sharp" meaning that it's a very precise temperature which must be achieved for the melting to begin (--the melting temp is also sometimes called the "fusing temperature" because the substance fuses as it's cooling, after having been melted)
....however, the "setting" temperature (of a thermosetting plastic, e.g. polymer clay, which doesn't even have a melting temperature) is not as sharp
.....so for thermosetting plastics such as polymer clay, the "best" temperature is just one at which it polymerizes at a reasonable rate
......the hotter the temperature, the quicker the setting reaction will happen... but, the reaction will still happen even at somewhat-lower temperatures --it just takes longer to finish
....(the DH says there's a rule for that ratio:."for every 10 degree C (18 F) loss in temperature, a reaction will proceed half as fast -- or in reverse, for every 10° C or 18° increase, the polymerization rate will double" ...it's an exponential change
.......that ratio actually makes sense for polymer clay especially when the curing time is much longer since so many people report baking lower and longer, and still getting strong clay --and sometimes just baking longer than minimum times for stronger clay in general --and also fits with some other bits of information I've heard over the years and couldn't explain
...
so baking time and temperature are interdependent --a trade-off
..(the darkening or ambering of the colors occurs because certain higher temps can cause side reactions, such as oxidation of the pigments and other materials)

Some people feel that since water boils at 212 °, anything less than 265-275 (or now 230 for new Fimo) will cause the clay to be underbaked and will not be strong (break or crumble later) or to leach plasticizer onto porous surfaces with long-term contact.
....many clayers feel that baking the clay longer than minimum time suggested, makes it stronger... many also feel this is true even at somewhat lower temperatures.
.....The total answer on strength-brittleness and temps-times isn't really in on this yet IMHO.

Since the instructions from the manufacturers in the past have included boiling, and since Scandinavians, e.g., have been doing that for a long time, I would suspect that the results for boiling are okay for some kinds of things.
....... There may even be something happpening with the boiling process which helps, that we don't realize yet (or just the polymerization rate would take longer?).. DB
....I actually made my first necklace (which I still wear) by boiling the beads at a simmer. Can't recall why except that the woman who owned the art store told me about it (1987). I read where someone says that it doesn't cure it properly. . .but that necklace is still in great shape today. Kay

I just checked a package (of Cernit) and it does say bake between 215 and 270. So boiling water (at sea level) might work. Bob
... a long time back I checked with the people at Polyform who said that the temperature that is on their packages is "the minimum temperature necessary for proper curing."
...the newest vesrions of FimoSoft and FimoClassic have a new baking temp of 230 F

IMO... read all you can about this, and/or experiment, then decide for yourself what makes the most sense from the info we know at this point.


(see also Beads –for boiling, Finishes for baking with sealers, Glues for baking with glues, Liquid Clays , Mixing Media, Safety, Paints, Transfers, Sanding, --or a particular technique, etc. )

Home