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Old Apr 01, 2012, 09:57 PM
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Southern Vermont
Joined Feb 2007
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Quote:
Originally Posted by gmwahl View Post
Steve. I wonder if a watt meter can be used for this. I am in the process of putting a new cutter together, two actually if you count a hot wire scroll saw that I'm also making the power supply for, so I may be in a good position to measure the voltage and amps while actually cutting as long as it doesn't take electrical engineering level skill

My two wires that I plan on using are stainless jewelers wire from Michaels, and .010-.021 guitar strings. I don't use nichrome to cut with but I am curious as to other types of suitable wire. I hope that the info that you get back from others includes some other nonconventional wire types so that we can actually see what readily available options we have out there.

If you think of a way to easily measure the V and A let me know and I will be glad to test and post my numbers

Thanks

Mike
Hi Mike!

Well a wattmeter would work, too if it's accurate enough and it's in line with the hot wire . The longer the wire, the more accurate it's going to be, so a short scroll saw type might not register much on the wattmeter, since it's designed to measure a lot of watts in a motor system.

But in a battery powered brushless ESC type power supply (like I think you have) it is often placed between the battery and ESC, and that won't give as good an indication of what the wire is getting because of losses in the ESC.

But any data would be appreciated!

Another way to measure the voltage and amperage is to just check the voltage across the cutting wire contacts with a multimeter. Record that. Then switch the meter over to amps mode (assuming the meter has at least a ten amp scale), disconnect one of the power supply lines to the cutting wire, and insert the meter in series with the power supply and the cutting wire (ie between them). This will then read the amperage figure. Record that. Done.

BTW when I said I wanted these figures while cutting -- I should have said when it is set for being able to cut. You don't actually have to be cutting foam! I just want those figures for when the wire is properly heated at cutting temperature.

Oh also, when making and breaking connections to meters, be sure to turn your power supply off. Natch.

Thanks for asking Mike!
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Last edited by vtdiy; Apr 01, 2012 at 10:15 PM.
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