Foam cutting

Hi

I have quite a bit of styrofoam stored away in my garage but no foam cutter. I can get nichrome wire easy enough but what about the power source and how to control it.

Any plans, instructions on making the power supply for foam cutting?

What voltage and currant ranges are needed?

If I know that, I can hunt around for a siutable transformer and other parts. Shouldn't be too complex surely?

You'll get all the info you'll ever need by doing a "google"
Try Foam Cutting or Foam wings
Cheers John

Use a soldering gun as your power source. You don't need nichrome wire. Use a thin straight wire pulled tight with a spring or bow. I used a steel welding wire .035 dia 3 ft long. It heats up slow about 2 minutes but it works great.

A large lionel or american flyer train transformer is good. It takes about 20-24 volts at maybe three amps to heat my SS safety wire cutter. The problem with Nichrome is it changes length alot with temp.

Adjustability and safety will be your main concerns with the power source.

I made a power supply using a couple of 12 volt transformers used for indoor halogen lighting (very, very cheap) and a circuit I found online. Don't use nichrome for cutting wire - use steel instead. Single strand stainless steel fishing line, or single strand CL wire, or guitar strings, or even plain old 7 strand CL wire all work well.

12 volts will probably drive a 22 inch bow - a 27-28 incher (which I consider the minimum, unless you want to cut 1/2-A wings only) needs 13-14 volts.

I used home-made equipment for a couple of years, but then I saw the TEKOA cutting machine in action at the old IMS show. WOW! I had to have one.

I have one now and am totally pleased with it. I can go in and cut a perfect core every time without having to practice or have help.

It comes with a current control power supply, so you can get perfect cuts no matter the length of the core.

My shortest cuts have been about 4", the longest 36", and no adjustment was required.

A plug for a video.... Good-To-Go Models has produced a two hour video on cutting your own foam wings. It includes just about everything you will need to get started. There is advice on making a your own bow, power sources(BTW dont use your soldering gun...AC at even low voltages can kill), making templates, even coring the wings. And for no additional cost you get several lame jokes. Anyway I have copies for sale as it was produced in my shop. The cost is $15 postage included here in the USA. I will take a check but prefer a money order as I dont have to wait for that to clear the bank before I mail the video.
Bob Furr
15872 Farnam Street
Omaha NE 68118

Bob Furr

Hi Bob,

Have to disagree on the soldering gun being dangerous as the voltage across the tip isn't but about 2 volts. What I can't fathom is how it would ever work in the first place.

where can i get info on the TEKOA cutting machine?

>where can i get info on the TEKOA cutting machine?

Found it with a google search in a list of manufacturers and suppliers. Looks the goods though finances will dictate a home made job for me.

Ken,
You may want to check the suitability of the foam you have stored away as first of there is many densities of foam which mean different wieghts and also foam does retain moisture from the air which will add to the wieght,as I have found out to my own expense, as I have mentioned here before I used to use foam for combat models and have tried packing foam that tends to be more dense than foam suitable for model airplanes.
How I cut my cores was with a dedicated bench that I had a home made bow similar to the old fashioned bow saw's but with wire instead of a saw blade permanently hanging on rollers suspended from the cieling and the power source was a heavy duty type transformer built into a box with I believe it is called a reastat for adjusting heat as it happened a fellow flyer made it for me, I tried nichrome wire but as others have warned it does stretch and then break you would be better of with a heavywieght single strand control line or as mentioned 7 strand c/l wire. I do hope this is of some help.

.....Dont let them grind you down keep on flying .....

I forgot try not to use a transformer with a thermal cut out it may trip halway through cutting the core.

shoot should have read what I wrote I meant dont use a transformer with a thermal cutout.

BY ALL MEANS GET ONE OF THOSE TEKOA CUTTING MACHINES!

ON