The cost for the parts is less then 10€ and only a drill and a saw is needed. First I went to my local diy electronics store and picked up a small box and a prototype PCB. The PCB has a bunch of small holes on it, in a 2.54 mm grid and a thin layer of copper. There are a few different versions of these with three or more holes connected with the copper or like this one just small squares around each hole. It doesn't matter what type you use as it will not be used as a PCB but rather just a plate with a bunch of holes.
The PCB was cut to fit the open side of the box, I also made a hole in one side of the box ti fit the hose for my vacuum cleaner.
Next up was two pieces of scrap wood I found at the summer house. Cut them to shape and made a rectangular hole that is slightly bigger then the box.
Cut a sheet of plastic that is slightly bigger then the hole and squeezed it between the woos using some clamps. For this I used 0.75 mm thick sheet. I will probably replace the clamps with some bolts and wing nuts later to make it a bit nicer.
I took some of the scrap PCB to raise the part to be copied off the board. this can help with getting a sharper edge on the bottom of the part.
Hooked up the box to the vacuum cleaner.
Held the sheet of plastic over one of the plates in the stove ti heat it up. This is the tricky part to get right, you want the plastic to be really soft but don't melt a hole in it. When using white plastic you can see when the center starts getting a bit darker it's high time to stop.This is something you will need to test to get a feel for. One good thing is that if the plastic isn't hot enough it will not be sucked down to the board and most likely you can just heat it up again and reuse it.
When the plastic is soft enough put the wooden frame over the box making sure the sheet is below the top of the box and turn on the vacuum cleaner. And we have a vacuum formed part.
A little bit of clean up and a second part and we have a 1/25 scale P-38 belly tank.
