Heating Nichrome Wire with 9.6V Battery - Newbie Help

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tkyleus
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Hello - I am a newbie looking for some basic help. I am working on a school project and need to heat about 24 inches of coiled nichrome wire. I am using a 9.6V battery ((1600mAh). It heats the wire nicely, but only lasts a minute or so. Do I need a Potetiometer to regulate the heat or some other device to make the heat conducted more sustainable?
 
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tkyleus,

Welcome to PF!

9.6V @ 1.6Ah = 15.36Wh

If you mean "heats the wire nicely" as being discernible heat rise, it should happen for a VERY short period of time. Resistive heat is terribly inefficient. To put this in another way, a 120V consumer resistive heater is generally ~1200W (10A). This would translate to 1.2kWh, or roughly 1.3% of what your battery is capable of. Another way, if your 15Wh heater were to produce 1.5kWh of resistive heat, it could do it for about 36 seconds.

I don't think there is any problem with your experiment, you simply need to realize the implications.

Fish
 
this maybe helpful:http://www.techlib.com/hobby/hotwire_foam_cutter.htm
In the world of foam model airplanes they often use car battery chargers
for power source. I use, for 12 inches of straight nichrome wire
smaller than a guitar string, a 200 watt lamp in series with a light dimmer and
the wire. Making sure the hot wire (black in USA) goes directly to the
dimmer switch and common (white) goes directly to the other end of the wire.
This is for cutting pink and blue foam.
 
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