Making a hot wire cutter

[Kody]

I am now ready to cut the foam down to be level with the timber frame. Once this is done, I can then glue on the last of the plywood to form the side wall. I don't know what gauge or diameter wire to use for melting thru the foam. I can buy some hard drawn stainless steel in many diameters. The stainless steel wire is very hard and springy, it actually makes beautiful tension springs. Can you guys recommend a diameter to use please? The length of the cutter is 28 inches and I will be using either a 12 volt battery or a 4 amp battery charger, whichever one works the best.

Kody

[Dale M.]

Actually nichrome (nickel-chromium) is better choice for hot element.... Gauge?, maybe something around 20 gauge... Voltage should be low (12 volts?) current what ever it takes...

http://www.omega.com/pptst/ni60.html

Dale

[desertmoose]

When I cut out my pontoons, I used .030 dia wire from my MIG welder. (Copper plated steel)



Worked great with a 12V battery charger for the power supply.

Length was around 40" or so, but I don't think it's that critical. Shorter wire will be hotter and cut quicker. mine was pretty slow.

Sam

[GuitarPhotog]

Here's a site about hot wire foam cutters. http://hotwirefoamcutterinfo.com/Introduction.html

They explain the relationship between temperature, wire gauge, and current.

I powered one with an AC adapter plugged into a lamp dimmer, and another with three 1.5V D-cell batteries (high current capacity rechargables).

<Chas>