Hot wire cutter wall wart not working

[agupt108]

Would it be possible to take the circuit of a hot glue gun and use it to build a hot wire cutter? Thank you!

 

[Merv]

Would it be possible to take the circuit of a hot glue gun and use it to build a hot wire cutter? Thank you!

Maybe, I don't know.
You are making this much much harder that is needs to be. Take an old 5v transformer, the kind that plugs in to a wall outlet, I call them wall warts. Get the largest one you can find, the big ones provide more amps. Take a board and put a couple of screws about a foot apart. Then take a thin wire and attach to the screws, attach you transformer to the wire.

5V and 1 amp should be about right for a foot of thin wire, about 26 gauge.

Here are 3 of my hot wire bows. They are nothing fancy, the small one, top left, has about a foot of wire and runs off of either a 5 or 12v wall wart, can’t remember which. This is the one I use the most often, it just easer to handle. The bottom one has about the same cutting wire but is long reach. I use it to break down 4x8 sheets of foam. I have another with even longer reach, not pictured. The long bow, top right, is used for cutting wings, runs on 24v.

I have other cutters that are for forming things, it used much thicker wire, about 16 gauge, it runs on 2V but 50amps. It's great for hogging out servo holes. Just bend the wire to the shape you want and cut away.

As I said before, Get the voltage about right then use a simple dimmer switch to power the transformer. Dial the heat in with the dimmer.

 

[danskis]

To answer you question: No

OK I was wrong. Look at this.

Hot Wire Foam Factory Crafter's Scroll Table | BLICK Art Materials (dickblick.com)

 

[agupt108]

Maybe, I don't know.
You are making this much much harder that is needs to be. Take an old 5v transformer, the kind that plugs in to a wall outlet, I call them wall warts. Get the largest one you can find, the big ones provide more amps. Take a board and put a couple of screws about a foot apart. Then take a thin wire and attach to the screws, attach you transformer to the wire.

5V and 1 amp should be about right for a foot of thin wire, about 26 gauge.

Here are 3 of my hot wire bows. They are nothing fancy, the small one, top left, has about a foot of wire and runs off of either a 5 or 12v wall wart, can’t remember which. This is the one I use the most often, it just easer to handle. The bottom one has about the same cutting wire but is long reach. I use it to break down 4x8 sheets of foam. I have another with even longer reach, not pictured. The long bow, top right, is used for cutting wings, runs on 24v.

I have other cutters that are for forming things, it used much thicker wire, about 16 gauge, it runs on 2V but 50amps. It's great for hogging out servo holes. Just bend the wire to the shape you want and cut away.

As I said before, Get the voltage about right then use a simple dimmer switch to power the transformer. Dial the heat in with the dimmer.

View attachment 235785

Thank you! I found a 12 volt 2 amp wall transformer...is that ok or should I use some resistor to dial it down?

 

[Piotrsko]

Thats 24 ish VA and expect the transformer to get hot really fast. Use a light dimmer to control. $17 for a router speed controller at harbor fright. Find a length of stranded extension cord wire and seperate a strand out.

 

[Merv]

Thank you! I found a 12 volt 2 amp wall transformer...is that ok or should I use some resistor to dial it down?

That will work for a test cut. With 12v, make your cutting wire about 2 feet long. Make sure to do the test in a well ventilated area, you don't want prolonged exposure to the fumes.

For testing, any thin wire will work, something like 26 gauge. You will eventually want to get nichrome wire, it is so much easier to control the heat and make great smooth cuts.

 

[agupt108]

That will work for a test cut. With 12v, make your cutting wire about 2 feet long. Make sure to do the test in a well ventilated area, you don't want prolonged exposure to the fumes.

For testing, any thin wire will work, something like 26 gauge. You will eventually want to get nichrome wire, it is so much easier to control the heat and make great smooth cuts.

I have steel fishing wire...will will that work?

 

[Merv]

I have steel fishing wire...will will that work?

Only one way to find out, I’d give it a try. You may need to play with the length of the wire, I’d tie your transformer wire to one end of the cutting wire, then slide the other transformer wire along the cutting wire until you get the temperature right. You are looking for the wire to just start to turn red. If it’s a bright red, that’s too hot. Start with about 2 feet of cutting wire, then slide you transformer wire along the cutting wire to shorten the cutting distance until you get the right temperature. You can also have a hunk of foam and place it on the cutting wire to test the temperature.

 

[agupt108]

Only one way to find out, I’d give it a try. You may need to play with the length of the wire, I’d tie your transformer wire to one end of the cutting wire, then slide the other transformer wire along the cutting wire until you get the temperature right. You are looking for the wire to just start to turn red. If it’s a bright red, that’s too hot. Start with about 2 feet of cutting wire, then slide you transformer wire along the cutting wire to shorten the cutting distance until you get the right temperature. You can also have a hunk of foam and place it on the cutting wire to test the temperature.

The steel wire conducted the electricity very well so no heating...I checked its resistance at 2.1 ohms; should have checked that before. Maybe get some 26 gauge nichrome?

 

[Merv]

The steel wire conducted the electricity very well so no heating...I checked its resistance at 2.1 ohms; should have checked that before. Maybe get some 26 gauge nichrome?

Most hardware store have some go look for some 26 to 30 gauge steel wire and give that a try but if you want to order some nichrome here's nothing wrong with that.

 

[cyclone3350]

The steel wire conducted the electricity very well so no heating...I checked its resistance at 2.1 ohms; should have checked that before. Maybe get some 26 gauge nichrome?

You definitely can't go wrong with the nichrome. That's all I use. However, one night, when I was out, I took the lower E string off an old guitar & was surprised that it actually worked.

 

[agupt108]

Most hardware store have some go look for some 26 to 30 gauge steel wire and give that a try but if you want to order some nichrome here's nothing wrong with that.

@cyclone3350 The guitar string heated up but very little; I could still touch it like metal on a particularily warm day, but nothing that would come close to melting foam. Maybe something wrong in my setup? Would a photo help?

 

[agupt108]

You definitely can't go wrong with the nichrome. That's all I use. However, one night, when I was out, I took the lower E string off an old guitar & was surprised that it actually worked.

I measured the amps that the transformer is putting out and the multimeter reads 0.3 ish; the transformer is supposed to put out 2 amps...

 

[Merv]

@cyclone3350 ...Would a photo help?

Can't hurt anything.

 

[Merv]

I measured the amps that the transformer is putting out and the multimeter reads 0.3 ish; the transformer is supposed to put out 2 amps...

If the meter is correct, that is way to low to be effective. Something near 2A is needed.

 

[cyclone3350]

@cyclone3350 The guitar string heated up but very little; I could still touch it like metal on a particularily warm day, but nothing that would come close to melting foam. Maybe something wrong in my setup? Would a photo help?

When I first started experimenting with foam cutting, I used an inexpensive table cutter from Hobby Lobby. It was on that one that I used the guitar string. After I did a few small projects, I upgraded & built one using Jacob's Online plans. U can see the set up here.

https://forum.flitetest.com/index.p...m-cutters-please-feel-free-to-weigh-in.69325/

 

[agupt108]

Can't hurt anything.

 

[Merv]

Can't see anything wrong. Must be a bad wall wart.

 

[agupt108]

Can't see anything wrong. Must be a bad wall wart.

I am not sure if I am on the right setting is 20m (DC A) correct? - of the multimeter

 

[agupt108]

Dont know if this helps but the first few times when the two leads touched they sparked; now it does not spark when touched. Might have shorted? Getting a steady 12.24 v though