Making a hot wire

[ghcoe]

I would double over the wire where it slid into the holes in the soldering gun. It doubles the thickness so the gun has something to stick to when you screwed down the tightening nuts.

[Fred Trout]

Good idea, next time will try it to see if it fits and file it down a bit if it doesn't. Wasn't sure if it was a compression clamp or something that had to be the correct diameter to drop in. A minor annoyance at any rate.

I was getting good at turning the gun sideways and melting my way out like turning a corner though

[ghcoe]

Just read though this again. Thought that I would mention that I found that instead of coiling the wire around a pencil that sticks up above the jig I now do it a bit different. I still use the pencil to coil the wire around, but instead of keeping the pencil in the drilled hole, I slide the pencil out of the wire and then stick the end of the wire in the pencil hole. This allows you to still have a means of adjusting the voltage, but keeps pencils out of the way. They tend to get hung up on stuff and make the jig top heavy for some cuts if you are using the gravity feed method.

[mikeschn]

Good idea Fred...

Mike...

[Mod - this needs to be a sticky thread, please ! ]

[GPW]

http://www.charlesriverrc.org/articles/ ... tterps.htm .... another alternative

[ghcoe]

http://www.charlesriverrc.org/articles/tools/joedydruliafoamcutterps.htm .... another alternative

Good information there.

[GPW]

One problem of a simple hot wire setup is knowing how much current the wire is drawing ... Here’s a simple conversion of our favorite Harbor Freight Freebie digital meter ... allowing you to adjust it to read up to 200 amps ... a bit more than we really need ... https://www.rcgroups.com/forums/showpos ... count=1369

So now we can read how much current we’re using ... just so we don’t melt anything .... other than the Foam ...

[rustytoolss]

I made a test hot wire cutter last night. It worked some what OK. I built it from what I had sitting in the garage. I used a 2x4 , the only wire I had was 1/16" welding wire. It cut through the foam in the channel shape that I bent. My biggest problem was that my battery charger kept setting off the circuit breaker (@2amp). The when it cooled down, I could continue .I do have a model train trans former, that I will try next. Does anyone use the Nichrome wire I've seen for foam cutting / is it really needed , and can you get it in a rigid form ?

[ghcoe]

How much wire did you have between the clamps? I find around 3 feet to be ideal with my charger. Not sure if a shorter distance may cause a problem or not.

[GPW]

We tried all kinds of wire over the years and the most durable so far is solid wire Fishing leader ( stainless steel) ... outlasted everything , even the expensive nichrome ...

[rustytoolss]

How much wire did you have between the clamps? I find around 3 feet to be ideal with my charger. Not sure if a shorter distance may cause a problem or not.

Yeah, I did use 3 foot of wire, just like your post said to do. I plan to put a small electric fan near the battery charger, to help cool it down. Might help ?

[rustytoolss]

We tried all kinds of wire over the years and the most durable so far is solid wire Fishing leader ( stainless steel) ... outlasted everything , even the expensive nichrome ...

How long of a fishing "leader" did you buy (guessing they come in various lengths) ? & were you using a transformer, or battery charger ? I assume it could be bent to form right angle edges.

[ghcoe]

When I was doing research on hot wires, I found one site that was using stainless steel welding wire for their hot wire jigs. They said it was the best wire they found that would hold the shape they wanted to make.

[GPW]

RT , the SS leader material came in a small package a few feet long , enough for a couple runs on my HW bow ... After breaking several other types of wire ( including Nichrome) One piece of the SS leader cut all the foam slabs for the FoamStream ... Variac as power supply ...
For cutting channels , we’ve used common Music wire set into wooden blocks , which worked fine with the Variac able to dial in the proper voltage ...

[rustytoolss]

RT , the SS leader material came in a small package a few feet long , enough for a couple runs on my HW bow ... After breaking several other types of wire ( including Nichrome) One piece of the SS leader cut all the foam slabs for the FoamStream ... Variac as power supply ...
For cutting channels , we’ve used common Music wire set into wooden blocks , which worked fine with the Variac able to dial in the proper voltage ...

What Is a Varica , power supply ?..never mind I googled it.