DIY Styrofoam Cutter

Editor's Note: CR4 would like to thank Johan van Niekerk for sharing another DIY story and sketches. Thanks again, Johan!

Cell phone chargers and other unused devices always seem to be lying around the house, ready to be thrown away. At the same time, trying to get my 10-year old grandson away from his computer and into the real-world can be difficult. For this DIY project, I built a Styrofoam cutter that uses household waste, and which provides a learning experience for my grandson. Cutting forms from Styrofoam packing pieces can keep a child busy for hours. But this device can also be used for serious purposes, too. In fact, it works nicely for building models.

Here are some sketches of the Styrofoam cutter I made using a 400-mm square piece of Masonite, 40 mm x 20 mm timber, 8-mm round brass rod (welding rod), and some odds and ends.

The timber is used to make an undersized frame on which the Masonite is glued, allowing the edge of the Masonite to extend about 15-mm over the frame on two sides. To allow for cutting to a set size, a clamp for a fence can be slid on the board.

The 8-mm round brass rod is bent to a radius of about 200 mm, and the one end pushed into a hole that is drilled in the middle-rear frame member. A brass clamp is made from a piece of 12-mm brass rod and drilled to slide on the 8-mm rod. The clamp is designed to take two 3-mm clamping screws: one to clamp it to the 8-mm rod and the other to clamp a piece of element wire.

For the bottom electrode, a piece of 3-mm brass rod is bent around a 10-mm former for about three coils. This forms a spring-like element that keeps the cutting wire tensioned. One end is pushed through a hole drilled in the middle-spar of the frame and then glued to keep it from rotating. On the other end, a clamp similar to that of the top rod is made.

Element wire is now strung between the two clamps (through a hole drilled in the board) and slightly tensioned. The charger wires are connected to the rod and the bottom coiled electrode. The cutting wire heats up, and the Styrofoam cuts easily with the wire. By sliding the top clamp on the rod, the angle of the cut can de adjusted. A piece of light angle can be used for a fence. Wing nuts and clamps can be adjusted for the cutting size.

For my cutter, I salvaged a socket from a discarded item and fixed it to the frame. I then wired the socket to the two electrodes. Now the charger is just plugged into the socket.

Editor's Note: Do you have a DIY story to share with CR4? If so, please message Moose or frankd20. We'd like to hear from you!