How to Build a Hobby Vacuum Forming Machine
If you would like an inexpensive way to make plastic molds, you may want to make a vacuum forming machine. It can be done in little time with supplies from your local hardware store. By building the vacuum former yourself, you can customize the size of the forming area and save alot of money. Hobby vacuum forming machines are basic, but they are pretty good at forming objects with a moderate amount of detail.
You will need to make the vacuum former and the frame. You will also need some type of vacuum sources, such as a shop vac or home vacuum cleaner. To build the vacuum forming machine, you start by making a box out of wood, mdf, or plywood. On one side of the box, you will need a hole with a fitting that is large enough to accomodate your vacuum hose. PVC plumbing fittings, such as bushings, work well for this. On the top of the box, called the forming area, you will either drill many holes for the vacuum suction, or you can just make one hole in the center and then cover the top with a piece of wire mesh or perforated aluminum. Either way, when you turn on the vacuum you should feel the suction.
It is very important to make the box as small and airtight as you can. This provides for the greatest amount of vacuum on the forming area. You might want to put some weatherstripping around the outside edge of the forming area to obtain a better seal. Another good addition is to make some guides for the frames to help you line things up in a hurry.
You will need two frames to sandwich the plastic. To make the frames, you can buy screen frame making materials. Cut the metal frames to size with a saw or rotary tool, and then you can use the plastic connectors they sell in the screen frame section to put it all together. To use the frames, you will put the plastic in between them and then secure it with binder clips that you purchase at the office supply store.