So i found a small transformer that converts 120 into 8 volt amps. Im no electrician but that seems ballpark of what everyone is using. Is that too much for nichrome setup with a 36" cutter?
Looks like there is some confusion here. Volts are not the same as amps.
I think what you have is a transformer that takes 120 volts and puts out 8 amps. Whether this will burn out your wire remains to be seen because it depends on the thickenss (and therefore the resistance) of your wire, which is not stated.
FWIW I have used an 8-amp battery charger with some stainless wire and it worked so-so. Problem is, I forget the wire thickness. Anyway, it wouldn't be relevant because your wire will have a different resistance than mine.
Use the search function, I think you'll find your answers there. Or risk it all and hook up the xfmr to your wire. If it starts to glow red, you should consider cutting the power immediately. Work in a well ventilated area. Please.
Get a variac.
Like the man said, it might be, it might not be. Check the volts, amps and watts listed on the transformer. Watts/volts=amps , amps*volts=watts , watts/amps=volts . If you have any two, you can find out the third.
Now, whatever amperage/wattage you have, it may or may not be too much for the nicrome wire, depending on the gauge (diameter) of the wire you have. I have found that the tables here are of use: http://www.wiretron.com/nicrdat.html
You can always put a rheostat in your circuit if the transformer puts out more current than you need. You want the wire hot enough to cut foam without dragging/offering much resistance. But if it's too hot, it can weaken and stretch, and where the hot wire stretches, it thins, gets hotter, thins more, gets hotter yet and breaks. That ain't theory, that's from busting more than a few wires.
And yes, do it with plenty of ventilation. The smell alone is bad enough, let alone the bad effects of the styrene vapors and smoke.
hope that's of use
doc...
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So i found a small transformer that converts 120 into 8 volt amps. Im no electrician but that seems ballpark of what everyone is using. Is that too much for nichrome setup with a 36" cutter?
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Get a variac or get another hobby!
Sorry there are short cuts and there is the sure thing.
If you have ask don't take the short cut.
Serious do is right and you will be happier with your results.
Surfding
Ever get a broken wire stuck in a block of foam? Yes they do get stuck when they break................................Do as Surfding says.
sounds like a variac for now. My father in law is a master electrican and said the math works out but you never know for sure how hot you need the wire to cut the foam and ect… We may use some different size cutters too so that would need a variac.
Thanks guys you are awesome as usual.
Gary Geist (LuckyLab) showed his 'down and dirty' method of controlling the electricity to his hotwire. He used a series of different sized light bulbs to get it right and cut some fine blanks.
Living dangerously, he used straight 120 AC current from the wall outlet and made sure he didn't touch the wire!
Again, pics lost in space....