When I was young (mid to late 70s) there was this toy I had that allowed you to make your own wax "hotwheels" type cars. It came with colored wax tablets, a bag of wheels, molds, and the "factory" where you molded the cars. Basically, you put the wax in the top, plugged it in, put some of the wheels in one of the molds, and when the wax was hot, you poured it into the mold and once it cooled, you had a wax hotwheel sized car.
I actually faked being sick one day so I could stay home from school and made about 15 cars.
I loved the thing, but for the life of me, I can't remember the name.
Ring any bells?