HOTWIRE I wish to use a piece of hanger wire,shaped so I can cut Foam.Wire must be cut specific form

Power source Question I wish to use a piece of hanger wire,shaped so I can cut Foam,But I need the wire large enough and tough.Car battery charger will get it hot,But how do I regulate???
Variac is to costly.cheaper alternative???

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do_too6 years ago
A few D cells and a wire hanger (smaller wire the better), will be sufficient to do portable rough cutting of lighter, less dense foam depending on what youre going for, nichrome (toaster, hairdryer, heater, etc...) and a variable power supply, old computer supply and a pot, or higher current A/C adapter for a non-portable seems to work quite well too, good luck, post the findings?..
Wiz1876 years ago
Use a dimmer running a step down transformer.
buzzy23776 years ago
BCH hobbies (Johnstown, PA) sells a hot wire cutter used in model railroading. The actual cutting wire is large enough to hold a shape.There are several extra pieces of wire for you to bend to your specific shape.

Dr.Bill7 years ago
Take an old electric heater apart.
Get the heater wire out.
Cut to the length you need.
Stretch it between 2 separate metal rods to hold the wire tight.
Attach power from a train transformer for variable power and variable heat.
klee27x8 years ago
12V car battery switched with a power mosfet(s).

Mosfet driven by a transistor on the output of a 555 timer IC in astable configuration.

Make the frequency in the 100Hz to 1kHz range. Use a small potiometer to change the duty cycle of the MOSFET. The duty cycle determines the power output.

All the parts (aside from car battery) can be purchased for about 10-20 bucks, and it can all run right off the same car battery.

Google "555 timer" "astable" "pwm"
Most performance oriented auto parts stores ( NAPA ) carry stainless steel lock wire which works quite well for that pupose
orksecurity8 years ago
Agree with the others. If you're using a hot-wire cutter, it has no need for thickness and indeed wants to be thin so it has higher resistance and heats up without drawing excessive amounts of current.

If your problem is that you want to cut a shape --  build a non-conductive "knife" which holds the thin cutting wire at its leading edge.
First off, it's a resistive load so you only need to use a potentiometer and secondly a large wire will be very hard to heat up, even with big amps.

You don't need to use a thick wire, the heat does all the cutting when you use one, for wire you can use nichrome, constantan or even try stretching out a small spring...
Sandisk1duo8 years ago
thinner wire