Hot-Wire Foamcutter (Battery Powered)

Step 5 Wiring

Two elements here.

Wiring the battery holder:

Attach a length of wire to each the positive and negative terminals of the battery holder. One length of wire needs to be long enough to reach the hole in the middle of the cutting board. The other needs to be long enough to reach the hole in the top corner of the board. (I attached washers to the end of these wires to make attaching them easier, I put a large washer on the shorter length and use it as a simple on off switch)

Wiring the hot-wire:

The required length of hot wire (nichrome) will vary depending on the type you have. Experiment with different lengths and 3 volts, use a length which produces a dull glow but does not cause the wire to melt. (takes a little trial and error)
Once you have the appropriate length figured out. Add a washer to both ends of it, twisting the wire to keep it connected (as in the photo)

Comments

[khang_ho]

Hello Clement, I am not very clear on the attachment of the lengths of wire to the battery holder. I am not too good at anything that has to do with electricity, so the fundamentals of what wire is supposed to be attached to what terminal is beyond me :0) I tried to make out the color of the wires and guess where they are attached, but no luck. It would help me a lot if you could add a diagram with the wires labelled, and the respective terminal they are supposed to be attached to? thanks, - KH

[n0ukf]

This is an extremely simple circuit. one terminal of the battery holder goes to the bottom end of the wire and the other goes to the top, through that bolt and washer that make up a simple switch. When I build my foam cutter, I'll use a variable current regulator so that I can set the current for a given thickness of wire and the length won't matter. Just turn it up until it barely starts to glow.