I build a vacuum forming machine out of some wood I had laying around in the garage, and a set of electric BBQ’s.
The households vacuum cleaner provided the vacuum, and after some failed attempts, I got succes!:
I had to cut them out, and give them the right size. After that I sanded them a bit, and used a ratle can to paint them matte black (the plastic had scratches). Because the plastic is fairly thin the surface is not super-smooth. But the matte black covers that quite nice.
See the next page where I’ve got them installed and tested.