Quick Tip: Tenting with Foil
This is a tip a lot of you have heard of. I'm writing about it because, while I had heard of it, too, I was skeptical that it would make a difference. Turns out I was wrong...
My polymer clay ovens get a bit moody sometimes. And it seems like that "sometimes" is usually right in the middle of a big deadline.
My previously-reliable oven had started under-baking things, a fact I didn't realize until some of my "finished" clay mosaic tiles were crumbly instead of nice and strong. (My oven thermometer had fallen off the shelf onto the element below, and I kept forgetting to retrieve it when the oven was cool. My bad.) A whole day's worth of clay stuff was under-baked, a fact I found especially frustrating since I was furiously working on projects for my book deadline.
I hate trying to find the sweet spot on an oven knob when the thermostat is off. It requires immeasurable patience: fiddle with the knob slightly, give it 10 minutes for the oven adjust its new temperature, check the thermometer, and fiddle with the knob again. It can take an hour or more to get the right temperature.
After messing with that process a while (and getting nowhere), I got impatient. I cranked the temperature way up and made a mental note to keep a very close eye on it, lest it overheat. Luckily for me, I also did something else. I tented the project with aluminum foil.
You know what's coming next. I lost my mental note and forgot to check the oven until the timer went off. I don't remember now what the exact temperature was, but I know it was above 300. I lifted the aluminum foil piece, expecting the worst. But, to my surprise, it hadn't burned or toasted. It was just fine.
My close call reminded me that, if I didn't have time to fiddle with an oven knob, I certainly didn't have time to lose projects to a hot oven. So I took the time to get it right. But I kept that tenting thing in the back of my mind, and decided to look into it a bit more when I had more time.
If you're not familiar with tenting, it's not an especially complicated process. Take aluminum foil (I use the heavy-duty stuff because it's stronger) and shape it into a pointed shape large enough to cover your item. I re-use the same piece again and again, tweaking its shape if necessary to accommodate taller or wider items. Just place it on top of your clay tile so it sits over, but doesn't touch, the item you're baking. Leave it in place until you're done baking.
I'd never messed with tenting before, because it didn't seem logical that it would work. And I won't pretend that I understand now why it works. Something about the heat being indirect? But it does work for me. I've even gone so far as to put my clay pieces, tented, in the oven while it preheats... and I always used to think that was a bad idea.
It served as a reminder to me that there's more than one good way to do things... and sometimes it pays to experiment with new methods, even if they may not seem intuitive. Live and learn.
What about you? Have you found a better way of doing things, maybe a way that you initially resisted?
Comments
Have I found a better way?
I should have initially researched toaster oven brands more deeply. Same for using and buying an oven thermometer. Same for polymer clay baking surfaces.
I've gotten the best and more consistent results, through three toaster ovens and other issues, by baking my clay items in one terracotta saucer (from the gardening section) covering the other.
Essentially creating a closed dome of thick ceramic is very forgiving of many things. The thick covered terracotta tends to stabilize the curing environment within it, avoiding over baking and helping a bit (nothing replaces observation and small adjustments) when an oven tends to have periods of cooler temperature during the bake or tends to run cooler as it ages.
All ovens spike their temps, some more than others. Also, I have had to bake on higher temperatures as an oven ages though. They don't always get up to temperature like they used to. The oven I'm using now is at that point. But I'm still getting good results, with some observation, some tweaking, and the teracotta baking technique.
I can get large enough and different sizes of terracotta saucers to accommodate different needs and things like bead trays, etc. Because of their texture, I don't have to try to tie or clip top and bottom together, as Laurie Mika did with two pans in her Mixed Media Mosaics book, pg. 17.
And they're relatively inexpensive! I just wish they came in rectangular form too.
For larger or more items, I believe covered terracotta saucers might also make curing polymer in one's regular family sized oven possible because they seal pretty nicely and I can't imagine how polymer clay residue would escape and cling to the inside of your oven, which is otherwise a concern and the very reason one is generally advised to bake in a dedicated oven? I wouldn't mind more discussion and feedback on that...
Posted by: Karen A. Scofield | August 1, 2010 1:02 PM
Karen, Thank you so much for sharing your tip! This had never occurred to me, but it sounds easy and inexpensive. I have always loved my toaster-oven sized pizza stone because it seemed to help regulate the temperature. It sounds like your version does that AND has all the benefits of tenting. Just last night I managed to nick my finished project with foil as I was tenting it for the oven, so the saucer version might be better than foil in that way, too. At least for smaller items. Do you know how large of a piece would fit inside the saucers? Sounds like a trip to the garden section is in my future.
As for whether this method would protect one's primary oven sufficiently, I have no idea. I've never tried placing two saucers together, so I don't know how tight the seal is. It seems logical that if most of the air is trapped, that should help. But I'm certainly not an expert on the chemistry behind the concerns, so I don't know if that's sufficient or not. You might try contacting Polyform's Customer Service to see if they would pass that question along to one of their chemists.
Thanks again for sharing!
Posted by: Angela Mabray | August 3, 2010 12:10 AM