As stated above, I use the oven in my home to heat the plastic. I have had no problems other than the hot plastic does not leave a family friendly odor. I try to do my forming when the wife and kids are out! It may not hurt to open a window or something also although the smell is not nearly as bad as some other hobby products we use nor does it linger for too long.

Finally you will need something to hold the frame off of the oven rack. When forming a part the plastic must be heated and allowed to sag. The larger the plastic sheet the more sag. I have made my frames so that they fit some aluminum cake pans I had on hand. The cake pans allow for a couple of inches of sag, which is more than adequate for the size sheets I normally work with. You do not want to allow the heated plastic to sag far enough to touch anything or it will stick and ruin the sheet. If this does happen, allow the sheet to cool and it will generally pop right off of whatever it is stuck to. Below is a pic of my frame with a sheet of plastic clamped to it and set on the appropriate sized cake pan. Notice I use small clips to hold the plastic to the frame. Make sure you have enough to securely hold the plastic while it is stretching. Also, make sure the clamps do not interfere with the forming bed so much as to prevent the hot plastic from forming an airtight seal. Ok, let's form a part.