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DIY Styrofoam Cutter

Styrofoam is the brand name for a polystyrene foam patented by the Dow Chemical Company in the late 1940s. Polystyrene foam can be used in a number of applications from keeping food fresh to packaging cargo for shipment or in model railroad building and theatrical set decoration. A hot foam cutter is a tool that enables precision polystyrene shaping. A foam cutter consists of a wire suspended across a small frame. The wire is connected to a power supply that heats the wire by sending out a low-voltage current. The wire becomes extremely hot and cuts through the foam like a hot knife through butter.

Things You'll Need

PVC tube, 1 1/2-inch diameter, 8 inches long
2 PVC tubes, 1 1/2-inch diameter, 6 inches long
2 PVC slip elbow connectors, 1 1/2 inches, 90 degrees
PVC glue
Steel guitar wire, E-string
Power Supply, variable, 2 Amp, single output
Electrical wire, insulated, 16-gauge, 8 feet long
2 eye bolts with wing nuts and washers, 1/4 inch by 2 inches
2 terminal ring lugs, 1/4 inch, insulated, solderless
Pliers
Wire strippers
Power drill and 1/4-inch drill bit
Electrical tape

Instructions

- 1
  Fit the PVC elbow connectors to either side of the 8-inch PVC tube. Insert a 6-inch PVC tube into the remaining openings of the elbow connectors. Secure the connections with PVC glue. The PVC tubes should form a U-shaped fork.
- 2
  Drill 1/4-inch holes through the 6-inch tubes, 1/2-inch from the ends. Insert an eye bolt through each hole, with the eye loops facing the inside of the fork.
- 3
  Cut the electrical wire into two 4-foot lengths. Strip 1/2 inch of insulation from each end of both wires using the wire strippers. Crimp a ring terminal lug to one end of each wire using the pliers.
- 4
  Attach a ring terminal to the outside-facing shaft of each eye bolt. Fasten the ring terminals to the eye bolts with the washers and wing nuts. One 4-foot wire should now be connected to the outside end of each eye bolt at the ends of the 6-inch tubes.
- 5
  Thread the guitar wire through each eye bolt on the insides of the 6-inch tubes. Twist the wire back around itself at either end to secure the wire taut across the eye bolts. Clip the excess wire.
- 6
  Connect the free ends of the 4-foot wires to the positive and negative terminal clips on the power supply. Turn on the power supply and test the foam cutter by turning the variable voltage knob to gradually increase the current through the wire.

Model Railroads