I wanted to explore packaging options, so I thought that I should explore thermoforming. Thermoforming takes a flat sheet of material, heats it up enough to be formable, then uses a suction table to suck it into a shape. It's a pretty simple concept. I thought that I should go ahead and make a thermoformer.

I have an old electric skillet, I thought it would make a good heat source. I have a big shop vac, that should make a good vaccum source. I just need to fabricate a suction table.

I drew up what I was imagining in Designspark Mechanical:

It's a pretty simple design. It's constructed of lasercut 1/4" plywood and 3D printed plastic corners. A 3D printed hose adapter comes out the side. I used an 8mm diameter rod that I had laying around (came out of an inkjet printer) as the hinge pin. Lasercutting is the way to go when you have hundreds of small holes to fabricate.

I took lots of pictures of the assembly. I figure if it works then I should make the thermoformer it's own Hackaday.io project.

I spent a while looking around online for a good plastic source. There are lots of places that you can buy thermoformable plastics, but they aren't low enough cost for what I'd like. This is packaging and I want it to be low cost. I decided to test Pepsi bottle plastic. Those bottles have a value of $0.05 in my home state and are readily available. The window that I designed in my thermoformer is sized just right to accept the plastic cut from the center for a 2 liter bottle.

Here is my full setup ready to test. I decided that a crescent wrench would make a good test subject.

Unfortunately my bottle plastic wants to shrink as soon as it is heated. It Really wants to shrink. My first attempt I cut the plastic just smaller than the screws in the frame. Tightening the screws was supposed to smoosh the plastic under the frame and hold it. No such luck. The plastic immediately pulled out.

Next I tried a larger peice of plastic that I punched holes in and threaded all the screws through. Surely that will strong enough to hold, right?

Not quite. The plastic wants to shrink with so much force that I tore itself out from the screws. Also, it never got pliable enough to be thermoformed.

The only other thing I had lying around was some 1/8" acrylic. I lasered a piece to the right size and gave it a go.

This almost worked! My skillet doesn't seem to have gotten the acrylic quite hot enough. I let it soak for a long time and then gave the thermoformer a shot.

Looks marginally wrench-ish! Sweet!

Unfortunately my Pepsi bottle plastic is a no a go. I need to find a better and low cost plastic to run in my thermoformer. Also, I'm not sure that my skillet can deliver enough heat.

To be continued...