Vacuum former: update 4

Progress at the end of the day

Today I mounted the platen to the vacuum chamber and finished the wiring.

The platen screwed down to the walls of the vacuum chamber; also shown is the frame bracket for holding the plastic

To attach the platen to the vacuum chamber, I first thought about using J-B Weld. However, I like being able to disassemble a piece of equipment for repairs, so I decided to screw the aluminum plate down to the wooden support. I put a screw in every 4 inches or so and it seems to be holding securely. I'll see whether it's air tight enough when I try to vacuum form something.

I finally got to the wiring today. Everything went together well once I found my soldering setup. I only needed to solder a couple of leads to the fuse holder. Everything else is attached with high temperature twist nuts. 

I wired in the shop vac first, and that worked great. Then I wired the heating elements and discovered that the pilot lamp doesn't work (I probably damaged it when removing it from the toaster oven), and that wiring all the heating elements in series doesn't generate enough heat.

I rewired so that two heating elements each are wired in series. Then the two pairs of heating elements are wired in parallel to the power switch. That worked much better so that the heating elements warm up very quickly.

With the wiring complete, I have the following items left to do:

  • Put a protective set of walls around the oven box. Those are exposed live wires when the power is applied
  • Add a latch to the frame bracket
  • add spacers to the frame bracket right next to the handle in order to remove some of the slop when moving the frame bracket from the oven to the vacuum
  • Add magnetic holds between the oven box and the frame bracket
  • Replace the pilot light