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Welder experts
splitrivet - 13/12/09 at 01:21 PM

Am I right in thinking that one of these http://cgi.ebay.co.uk/JG-50-A-Air-Plasma-Cutter-torch-50A-12-feet_W0QQitemZ350273313192QQcmdZViewItemQQptZLH_DefaultDomain_3?hash=item518dea99a8 providing the connections are OK could be fitted to my DC Tig welder and turn it into a plasma cutter or am I just being dillutional.
Cheers,
BOB

coozer - 13/12/09 at 01:32 PM

Don't plasma cutters use compressed air as well??

MakeEverything - 13/12/09 at 01:33 PM

I dont think theres any reason why it wouldnt work on an AC TIG as well.

Might consider one for myself at that price!!

MakeEverything - 13/12/09 at 01:34 PM

quote:
Originally posted by coozer
Don't plasma cutters use compressed air as well??


Or oxygen mix, but its only purpose is to "Blow" away the molten slag.

splitrivet - 13/12/09 at 01:44 PM

quote:
Originally posted by coozer
Don't plasma cutters use compressed air as well??

Combined with a compressor of course.
Cheers,
Bob

wilkingj - 13/12/09 at 01:49 PM

Plasma cutters use compressed air, not O2 or any other gas.

I think you cant use a plasma torch on a std TIG. I think the voltage is different for a TIG to a plasma Cutter.
I am not exactly sure, but I think the plasma cutter uses a mugh higher voltage than a TIG set.

Unless you have a special Dual Mode set, it wont work on a Std TIG machine.

flak monkey - 13/12/09 at 01:49 PM

Welders are high current, low voltage (30v open circuit). Plasma cutters are low current high voltages (10,000v+) so no, it wont work.

David

mark chandler - 13/12/09 at 02:06 PM

dillutional, sorry

daviep - 13/12/09 at 02:45 PM

quote:
Originally posted by MakeEverything
quote:
Originally posted by coozer
Don't plasma cutters use compressed air as well??


Or oxygen mix, but its only purpose is to "Blow" away the molten slag.


That's not really an accurate description.

The high voltage DC ionises the gas so that it forms an extremely high temperature "plasma stream", it is the plasma stream which cuts the workpiece. It does also carry the melted material out of the cut.

MakeEverything - 13/12/09 at 04:57 PM

quote:
Originally posted by daviep
quote:
Originally posted by MakeEverything
quote:
Originally posted by coozer
Don't plasma cutters use compressed air as well??


Or oxygen mix, but its only purpose is to "Blow" away the molten slag.


That's not really an accurate description.

The high voltage DC ionises the gas so that it forms an extremely high temperature "plasma stream", it is the plasma stream which cuts the workpiece. It does also carry the melted material out of the cut.


splitrivet - 13/12/09 at 08:06 PM

Well thats another bag of chips well and truly pee'd on then.
Cheers,
Bob

MikeRJ - 13/12/09 at 09:06 PM

quote:
Originally posted by flak monkey
Welders are high current, low voltage (30v open circuit). Plasma cutters are low current high voltages (10,000v+) so no, it wont work.

David


They only use that much voltage to start the arc, just like a TIG with HF start. Voltage when cutting is much lower (~140v), though still higher than a TIG.

flak monkey - 13/12/09 at 09:10 PM

I thought they maintained a high voltage to create the plasma stream?

Or is it a case of once the plasma is flowing it doesnt need a big voltage differential to maintain it?

JoelP - 13/12/09 at 09:57 PM

think it will be like a lightning machine, huge volts to create an arc but once the air is ionised the resistance will be much lower.

MikeRJ - 13/12/09 at 10:14 PM

quote:
Originally posted by flak monkey
I thought they maintained a high voltage to create the plasma stream?

Or is it a case of once the plasma is flowing it doesnt need a big voltage differential to maintain it?


It's just like a TIG arc, once the arc is struck the resistance drops significantly so lowers the voltage required to maintain the arc.

Peteff - 13/12/09 at 11:50 PM

quote:
Originally posted by mark chandler
dillutional, sorry


Delusional ? Sorry the tig won't power a plasma arc or there would be a lot more tigs being sold as dual purpose machines.

flak monkey - 14/12/09 at 08:00 AM

quote:
Originally posted by MikeRJ
quote:
Originally posted by flak monkey
I thought they maintained a high voltage to create the plasma stream?

Or is it a case of once the plasma is flowing it doesnt need a big voltage differential to maintain it?


It's just like a TIG arc, once the arc is struck the resistance drops significantly so lowers the voltage required to maintain the arc.


Now I know Thanks for that

[Edited on 14/12/09 by flak monkey]