How to Make Styrofoam Cutter
Styrofoam is the trade name of Polystyrene which is a petroleum-based plastic made from the styrene monomer. Polystyrene is a light-weight material that is good for insulation purposes. Styrofoam can be used for building materials, including insulated sheathing, pipe insulation and floral and craft products. If you are working with Styrofoam projects you may want to have your own cutter. The hotwire foam cutter is the popular choice as it melts through the foam as opposed to sawing or sanding; here’s a guide to make your own.
Tools Required
- Utility knife
- Wood saw
- Drill
- Screw driver
- Twist ties
- Electrical and packaging tape
- Nibbler
- Wrench
Materials Required
- 2 ft, 16 gauge extension cord
- 2 wooden yard sticks
- 4 #10-24 x 1.25″ machine screws with nuts
- 10 #10 washers
- 28 SWG of nichcrome wire
- Single pole dimmer switch.
- 15 volt, 2 amp transformer
- An electric guitar string, about .10 – .16 size
- A length of 2 conductor electrical wire with a regular plug on the end
- A piece of wooden dowel or stiff plastic rod about one foot long
- Project box
Instructions
- Cut one yard of stick in half, and then drill 3 holes in each half. Holes should be in the middle and ½” from each end. There may be an existing hole in one end, if so you will only need to drill 2 holes.
- With the second yard stick drill a hole 6” from the existing hole and the second hole 1” from the opposite end.
- Use the machine screws to loosely bolt the frame together in an “H” shape.
- Attach the lead wires to the frame – cut each end of the 12ft extension cord and strip one end of the insulation (1/2”).
- Place a machine screw at the top of the right leg of the “H”. Use one washer on the head of the screw and the other on the nut side. Don’t tighten the nut all the way down.
- Bend the stripped wire of the extension cord into a U shape, and place it around the screw between the two washers and tighten the nut.
- Pull the two conductors of the cord apart for about 3 1/2 feet. Cut the unmounted side of the split to one foot. Strip the end of the one foot section and hook it to the other leg of the H in the same manner in which the first wire was done.
- Close the wire using twist ties.
- Use the beaded end of the guitar string to make a loop and hook it over one terminal. Ensure it doesn’t touch the wood.
- Pull the frame legs to each other until the loop on the other end is tight.
- Wrap the end of the wire around the end of the other terminal screw and twist.
- Now to keep the square to the wire – Tie a loop in one end of a 3 foot piece of string and hook it under the washer of one of the middle screws. Thread the other end of the string though the hole in the opposite leg.
- Square up the frame and tie the string. Repeat with another string for the other side ensuring there is tension. Now both of the criss-cross strings should be pretty tight, and there should be slight tension on the wire.
- Apply tension by inserting a ruler in the tensioning loop. When there is enough tension slide the ruler down the yard stick.
- Wire the transformer and dimmer switch. Place the two conductor wires into the wall plug and the brown wire to the hot wire.
- Inset the transformer into the project box.
- Check all wiring before attempting to turn on the foam cutter.
Tips and Warnings
- Use power source with variable voltage control
- Ensure transformer container has some sort of air flow
- Turn up the dimmer slowly
