Styrofoamcutter problems

[stereodreieck86]

Hello fellow modelers,

I have bought a Styrofoam cutter on Ebay (https://www.ebay.de/itm/133189036346?ViewItem=&item=133189036346) and assembled. The entire construction is powered by a 3S battery controlled by a brush regulator and servo tester. The bow is over a meter wide but the maximum current is only measly 0.9Ampere in the result, the cutting speed is not sufficient and the heat barely enough to cut the foam.
If I move a clamp on the wire and thus shorten the arc, I get a higher current (1.2Ampere) but then I have less cutting width available to increase the voltage would certainly also be a possibility but then I would have another ( expensive) regulator (6S capable) buy.

Have I overlooked something or is the higher voltage the only solution?

 

[Merv]

You could try a different gauge wire. I have used this wire for years and have purchased several transformers. I use a transformer and a light dimmer to control the temp. Never thought of using an ESC. You might try calibrating the ESC.

https://www.jacobs-online.biz/nichrome_wire.htm

 

[stereodreieck86]

I found this chart for my wire, it's a 0.36 mm thick. 6,9Ohm according the chart, that's a lot of resistance.

 

[skymaster]

You could try a different gauge wire. I have used this wire for years and have purchased several transformers. I use a transformer and a light dimmer to control the temp. Never thought of using an ESC. You might try calibrating the ESC.

https://www.jacobs-online.biz/nichrome_wire.htm

could the wire from a hair dryer be used as a wire cutter

 

[Merv]

could the wire from a hair dryer be used as a wire cutter

Yes, I believe it could be used. It would be nichrome, but it will be coiled, not sure if you can make it straight enough. It might make ridges in the foam.

Just about any wire will work. I started using steel wire from the hardware store. Nichrome wire definitely work better & last longer.

This website has all the information you need, they have great prices on wire & transformers.
https://www.jacobs-online.biz/nichrome_wire.htm

 

[cyclone3350]

Yes, I believe it could be used. It would be nichrome, but it will be coiled, not sure if you can make it straight enough. It might make ridges in the foam.

Just about any wire will work. I started using steel wire from the hardware store. Nichrome wire definitely work better & last longer.

This website has all the information you need, they have great prices on wire & transformer
https://www.jacobs-online.biz/nichrome_wire.htm

Yes, I believe it could be used. It would be nichrome, but it will be coiled, not sure if you can make it straight enough. It might make ridges in the foam.

Just about any wire will work. I started using steel wire from the hardware store. Nichrome wire definitely work better & last longer.

This website has all the information you need, they have great prices on wire & transformers.
https://www.jacobs-online.biz/nichrome_wire.htm

@Merv , I see that U built a Jacobs cutter. Have U posted any of your builds using it? I have built one years ago and made the wings and tail for this thing. I misplaced it and had to build another and now I really want to make use of it. Still in the learning stages and looking for ideas. My current project is on my post https://forum.flitetest.com/index.php?threads/pink-foam-kind-of-sort-of-f-5.67758/. The swept back surfaces R posing a real challenge. Is there a foam cutter forum?

 

[Merv]

I see that U built a Jacobs cutter.......Is there a foam cutter forum?

I built my own cutter, I didn’t run across Jacobs until mine was finished. Ended up using his nichrome which makes much easier cuts, better temperature control. His transformers would have been cheaper than the ones I found.

I’m not aware of a foam cutter form.

 

[skymaster]

Yes, I believe it could be used. It would be nichrome, but it will be coiled, not sure if you can make it straight enough. It might make ridges in the foam.

Just about any wire will work. I started using steel wire from the hardware store. Nichrome wire definitely work better & last longer.

This website has all the information you need, they have great prices on wire & transformers.
https://www.jacobs-online.biz/nichrome_wire.htm

a few months ago i stopped at a goodwill store and grabbed a hair dryer for the purpose of taking the wire out and make a hotwire cutter. and yes i did came to the problem of making the wire straight. while trying on a small piece of the wire i found out what you are talking about making the wire straight, so i ruined that piece because i tried pulling it to make it strait and it got ruined. but i found the solution to this. for me the wire was wound up in small coiled pieces, so what you do is you get a nail and stick it into the coil and grab the end of it and pull the wire uncoiling it from the nail and what you get is a nice uncoiled wire and ready to use.

 

[Merv]

There is another trick to get straight wire. Hold one end securely, like in a bench vice or on a nail, chuck up the other end in a drill. Pull the wire hard & give the drill short a spin, be careful not to spin too much. Done correctly the wire will be straight as a string, like music wire straight.

I regularly do this with steal wire, to make great push rods for indoor planes. I’ve never tried it with nichrome.

 

[skymaster]

There is another trick to get straight wire. Hold one end securely, like in a bench vice or on a nail, chuck up the other end in a drill. Pull the wire hard & give the drill short a spin, be careful not to spin too much. Done correctly the wire will be straight as a string, like music wire straight.

I regularly do this with steal wire, to make great push rods for indoor planes. I’ve never tried it with nichrome.

so what type of transformer should i get to build a hot wire cutter. what did you guys use to build one?

 

[Merv]

so what type of transformer should i get to build a hot wire cutter. what did you guys use to build one?

It depends on the gauge of wire & how long of a wire you want to cut with, the longer the wire, the higher amperage you will need. I have 3 different transformers that I use depending on the application.

These two web pages should get you going in the right direction.
https://jacobs-online.biz/wire-xformer_selection.htm
https://jacobs-online.biz/calculators.htm

Here is a picture of my transformers, I use 26 gauge wire for wings & 16 gauge wire for forming a profile of something.

 

[cyclone3350]

so what type of transformer should i get to build a hot wire cutter. what did you guys use to build one?

I would watch this video to see if U want to go this specific route. Most of the parts can be purchased from https://www.jacobs-online.biz/nichrome_wire.htm as @Merv stated earlier. There are many videos on youtube that have many ways to build a power supply. Watch a few and see what looks feasible for U. I built the one on the video and found it to be very complicated. Probably more than it needed to be. Plus U R using household 110v A/C which could be very dangerous. I will say that I am pleased with the way this one works for me. I went with the XFE0512E 12/24v transformer so that I can power a 30" bow. After building one, I am finding that it is a huge learning curve to using it. Plus there are a variety of foam choices and I am slowly learning which one suites me. My first cuts used white insulation boards for the wings on the Cassutt racer and for the wing core on my prop F-5.I used craft white foam from HobbyLobby for Russian PropJet. Right now, I am using Dow Corning pink insulation as I have used on the pattern plane on my previous post. Maybe we can start a forum for others out there to way in on foam cutting. I see a lot of potential here for an alternate way of building.

 

[Merv]

Great looking planes

 

[cyclone3350]

Thanks @Merv

 

[stereodreieck86]

Hey guys,

I am currently living with my sister and nephew in a less than optimal Livingsituation, I now longer have a room for myself or a workshop.
Because of this I put all Foamcuttingprojects on hold, but I am still working on some projects that require very little space like a Conversion of my Robbe Skyflex 2000 to a Nightflyer and finishing my RobbSkyflex V.

Thanks for all the tips.

Cheers
Nik (from Germany)

 

[Pieliker96]

Hey guys,

I am currently living with my sister and nephew in a less than optimal Livingsituation, I now longer have a room for myself or a workshop.
Because of this I put all Foamcuttingprojects on hold, but I am still working on some projects that require very little space like a Conversion of my Robbe Skyflex 2000 to a Nightflyer and finishing my RobbSkyflex V.

Thanks for all the tips.

Cheers
Nik (from Germany)

I love Rogallo wings, they're so cool