Hi ,

I was wondering what gauge of nichrome wire would be adequate for cutting foam wing cores ?

Thanks ,

Rob Killick

Hi Ralph ,

Thanks for the info . I checked a few do-it-yourself foam cutting sites and most of them use a 20 gauge wire ,
I checked and .008" wire is 32 gauge

Thanks again ,

Rob Killick

Hi Guys,

If someone has a "Feathercut" wing cutter system then you must only use their wire, which is .018 T-370 inconel wire. They warn that using nicrome or other wire could harm their power source, so I only use their wire with my Feathercut. you can get the wire from "Aerospace Composites", "CST" composites store and of course directly from Feathercut.

I also have a rheostat power source which can use other wires. I don't like nicrome wire because I have had it heat deform and ruin cores even with lots of tension, plus it broke on me much more than any other wire I have used.

I have used .012 and .008 braided control lines and it holds up well and gives consistent heat. I am thinking about trying .008 solid control lines next. I looked online and I found references to others using control line or guitar strings and etc because they did not like nichrome. I am sure some folks have had perfectly good results with nichrome but I and others have not, and control line is a much cheaper and easier to find alternative.  

The Feathercut guy reccommends using sandpaper to thin the wire on the side that cuts the shorter wing chord when cutting a tapered wing. the wire has to move slower across the shorter tip chord than the wider root chord and this can cause an excessive burn out and produce inaccuracy in the cut. Sanding the wire reduces the burn out at the tip and yeilds a better core. I went ahead an thinned the wire but I didn't do side by side comparisons with an unthinned wire to compare results so I can't personally swear thinning is better but I figured it couldn't hurt.

This may be more information than you were looking for but I thought I would pass it along.

PS. I just saw Bob Furr's post about using control line for your bow. See I told other guys were doing it

                                                                   Happy Foam Cutting,
                                                                                                Pat Robinson  

Pat,
I think you may be happier with the larger solid wire Howard suggested as the resistance in .008 solid would be quite high and I am guessing you could make a nice flash bulb out of it... resistance seems to be related to the surface area of a wire (this is one reason that extension cords are made up of many very fine wires) and the .008 solids have much less surface area than the stranded wires.

Bob

In the video I use a dowel rod for the bow.   I think my next bow will be a wooden yard stick from Ace hardware.   It is almost as light (which I have found to be really helpful in making accurate cuts) and is more durable than a dowel rod (and less expensive).   I am not sure why I so love finding frugal ways to have fun in this hobby but I do....
Bob