HelpI'm looking for a better method to cut foam...

[Crazed Scout Pilot]

I am a mad scratch builder and have been cutting foam board with a razor blade but would like to try building a hot wire cutter. I think it will be easer. Could some one draw me an diagram of the easiest way and cheapest way to make my own hot wire cutter. I have scrap wood 20 gauge steel wire I have extra push rods from FT kits I have a 3 cell 2200 mph battery and an esc and some screws laying around. Im 16 and don't have a job so I can't really buy anything else. Is that all I need or do I need something else? I appreciate your help. thank you.

 

[Shurik-1960]

I am currently in Moscow, but the day after tomorrow I will go to the country and take a picture of my cutting machine: sheet chipboard and 2 furniture sleds along the edges. This machine can be automated, but I like to cut manually. The wings can be cut in the shape of a rectangle and a trapezoid. The quality is much higher than cutting onions.

 

[Piotrsko]

I use a router, roto zip and tablesaw. All with new sharp blades. Sometimes my belt sander. YMMV

A hot wire cutter is basically some sort of insulated frame that holds the wire taught, a power supply and and some thin strong wire. There was a how to somewhere on this forum

 

[Merv]

Here are some of my hotwire bows. They are very simple, cheap and easy to make. Use whatever scraps you have lying around.
A steel wire will work, just to try it out. Nichrome wire is by far the best, much easier to control the heat. Controlling the heat is the trick, to cold & it will not cut, too hot & the kufr is too large. I use various transformers, 3V 5V 12V & 24V depending on the application. I use a simple light dimmer switch. Just plugin the transformer into the dimmer & then fine tune the heat. All of the bows pictured use 26 gauge wire. I also use 16 gauge wire, it will hold whatever shape you want. It's great to make servo pockets and other shapes.

Here is a great site with lots of useful information, he sells all of the products, transformers, wire etc. Spend some time exploring his site.

Products for Industry, Laboratories and Hobbies

 

[Crazed Scout Pilot]

Thank you guys for your help much appreciated.

 

[Shurik-1960]

I made my cutting machine by viewing this article : https://www.parkflyer.ru/ru/blogs/view_entry/10167/ .The most excellent quality wings are obtained on this machine.Before cutting, I check the cutting temperature on a piece of foam.The best cutting temperature- there should be foam hairs after cutting.High temperature -strongly melts the foam and the surface will be slippery and poorly sanded.

 

[Crazed Scout Pilot]

Thank you for your help and tips!

 

[Crazed Scout Pilot]

Am I able to take a brushless esc and use two of the motor plugs to send voltage to the wire?

 

[FlyBreakFixFly]

Using two ESC outputs seem like a bad idea. What about using a charger with a power supply mode instead?

 

[Shurik-1960]

My power supply for the foam cutter: a transformer, a dimmer, 4 diodes-a diode bridge, wires with crocodiles and a power cord. I have been using it for more than 12 years. Photos of the received half - wings .You can connect a car battery to the foam cutter.But the quality will be low-there is no adjustment of the heating of the string.

 

[Shurik-1960]

I took a picture . Added: a small wing for a Chinese throwing glider and a half-wing marriage for the Wiesel project from a Chinese throwing glider.Marriage will take a very long time to hide.....

 

[Crazed Scout Pilot]

Using two ESC outputs seem like a bad idea. What about using a charger with a power supply mode instead?

Thats great how do I hook up my bow to my charger? My charger is this batt go ISTD charger.

Thank you for your help.

 

[Crazed Scout Pilot]

My power supply for the foam cutter: a transformer, a dimmer, 4 diodes-a diode bridge, wires with crocodiles and a power cord. I have been using it for more than 12 years. Photos of the received half - wings .You can connect a car battery to the foam cutter.But the quality will be low-there is no adjustment of the heating of the string.

That sounds like a good system. But i'm quite a ignorant when it comes to electrical stuff. I just figured out how to solder a battery connecter on a couple months ago. But I do appreciate you help and It looks like you got a pretty nice system down.

 

[FlyBreakFixFly]

If that were my setup: I'd wire up the bow with a positive and negative lead. Have enough wire length to move it around if needed. Terminate the wires into an XT60 or EC3 connector, it doesn't matter which goes where since it's DC voltage. Then experiment with settings on the power supply function to see what works.

 

[Crazed Scout Pilot]

Thank you so much that was very helpful! What type of wire should I use? Currently I have the voltage set at 4.20 volts. Should I change the voltage? To get it running do I just set it like I am going to charge a battery and then press charge and that will stat to heat the wire up? I'm just a bit concerned with electricity I don't want to shock my self or set something on fire. I really appreciate your help! I had almost given up the idea because i don't have the money for any dials or switches, but I do have a battery charger and it sounds like this is going to work.

 

[FlyBreakFixFly]

There should be a specific "power supply" mode on your charger. That will allow for dialing in the voltage. 4 volts means a ton of amps. That means a heavy gauge wire. A higher voltage means fewer amps for the same wattage. Fewer amps means thinner wire can be used.

I'd research what other people have done for constructing their foam cutting bows. And find out how to access the power supply mode along with what limits it has. That should be instructive on what it can do.

 

[hankflies03]

@Squashymoon125 you made one right? how did you make that?

 

[Shurik-1960]

Take as a basis in your life the principle: if you can't do well, it's better not to do it!! Onions can be welded from polypropylene pipes with a special soldering iron. On your photo - there is a sample of how not to do it!

 

[Crazed Scout Pilot]

There should be a specific "power supply" mode on your charger. That will allow for dialing in the voltage. 4 volts means a ton of amps. That means a heavy gauge wire. A higher voltage means fewer amps for the same wattage. Fewer amps means thinner wire can be used.

I'd research what other people have done for constructing their foam cutting bows. And find out how to access the power supply mode along with what limits it has. That should be instructive on what it can do.

Success has been achieved! Really grateful for you help with the charger. I built a bigger bow and was able to get it hooked up to the charger. Thank you.

I used a guitar string for the wire. I did a lot better then my 20 gauge ss wire. Now I have to make a deeper bow. This one was a bit shallow.

 

[Crazed Scout Pilot]

@Squashymoon125 you made one right? how did you make that?

Are you wondering how I made my hot wire bow? Or did I miss your question?
If your wondering how I made my hot wire bow I would love to share how i did it with you.