An easy to build, cheap, vacuum former.

Cut out one of each svg OR dxf file on a laser cutter or CNC out of 1/4" plywood or mdf (actual thickness should be 0.2-0.208).

3d print (1) hose_adapter.stl, (4) post_holder.stl

Fit the frame pieces together, and use CA glue on the seems. Seal inside joints with silicone.

Assemble as seen in the sketchup file.

The top piece in the sketchup file is cement board.

Take apart a portable heater, or use a power supply and nichrome wire for the heating element. Any heating element will work. Use ceramic posts if possible to attach the heating wire to the cement board.

Use a shopvac or vacuum pump (~3CFM) for the suction.