A while ago I was in Radio Shack (before they closed all their stores) and I found Thermoplastic on sale: $5 for 300g. It looked like a great price so I grabbed the only box they had left. At the time I had no idea what I would do with it, and frankly I still don’t.
My daughter and I were bored tonight. So I went down to my shop to see if there was anything we could play with and I spotted the thermoplastic. My daughter is usually more creative than I am so I though I would heat it up and let her play with it.
All you need to do to mold the plastic is heat it up to 140°F, which you can do by heating a cup of water in the microwave and then dumping a bunch of the pellets in the water. The pellets are ready to mold when they turn clear. So I grabbed a spoon and scooped them out. While the water is hot enough to burn you, the plastic is comfortable enough to work with. It also is a little sticky, not only will the pellets start sticking to themselves in the cup of water, but they will stick to the side of the cup and the spoon too.
At this point you can mold it into whatever shape you wish. I molded a dog and my daughter molded a marshmallow (which she doesn’t want shown). When the plastic turns cloudy it starts to get hard. At this point you can heat it up again and try again if you’re not satisfied with the shape. When you are done you can either wait for the plastic to cool or you can run it under cold water. You can melt and form the plastic many times if you wish. I would imagine that the plastic would start to get dirty colored if you weren’t careful.
I also tried molding a wolf head for a LEGO mini figure. It is pretty crude, but i’m pretty happy for a first try. I did discover that I should have used a releasing agent though because the thermoplastic is stuck to the mini figure body and I can’t get it off.
Another experiment I’d like to try is coloring the plastic, I’ll have to research tat one a bit before I try it.