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Old Apr 02, 2012, 03:42 PM
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Southern Vermont
Joined Feb 2007
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BTW, this data from Harry D already shows us something to answer a lot of questions often asked.


"My power supply is a 12 volt supply rated at 2 amps -- will it be adequate for a hot wire cutter?"


If a bow for foam requires about 1.5 watts per inch of cutting wire, and you can supply about (for conservative sake) about 75% of your rated supply in watts:

75% x 12V x 2A = 18 watts

18 watts / 1.5 watts per inch = 12 inches.

Your power supply can supply a wire cutter of about 12" in length -- this can cut 12" wing panels. (if you glue these together as required for a dihedral wing, your simple wing capacity is 24" -- or you can glue multiple panels end to end to make a wing of any length).

"Yes but I want a wire cutter that can cut a 24" panel. What do I need for a power supply for that?

Answer, well you could go with either a 4 amp 12 volt system, or a 24 volt 2 amp system, or any other combination that gives you about 48 watts output.

"Yes but what is the difference between a 48 watt system that runs on 12 volts and one that runs on 24 volts?"


The 12 volt system will use thicker cutting wire to achieve 48 watts, while the 24 volt system will require thinner wire. Or, the 12 volt system needs a wire composition of lower resistance than the 24 volt system to achieve 48 watts. You can go with either alternative, or even a combination of the two. A calculator can help you decide which combination is best for you

Of course all of the above requires a little more user data to confirm what the useful wattage per unit length range is.
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