Cheap TIG

[Jan]

I'm considering adding a scratch start TIG gun to a stick welder as a cheap go at DC only TIG welding before (maybe) going on with a dedicated TIG/arc machine.

My first question is about the gas flow. Do the little switches on such guns control a gas valve or something else?

Then is a simple on/off foot switch a good idea?

What are the odds that a used gun will be well past it's use by date?

What's the best size (model number?) to go for if I don't expect to go much over 100 amps?

Obviously there will be other things I haven't thought of, so the answers to them would be much appreciated.

Many thanks in advance.

 

[Jan]

In the same vein: Apart from the gas used - and maybe flow rate - what's the real difference between a TIG gun and a plasma torch?

 

[shenion]

A WP17 torch will do up to 150 amps. A Cheap Chinese one a bit less.

You can use a switch or pedal to control the gas flow. Jody at weldingtipsandtricks.com used a big knife switch for a footedal to control the current. I think it was ab battery disconnect for an RV.

Plasma is completely different, they run hundreds of volts (my small 25A one says 280V.) They also have complicated arc starting methods.

 

[Jan]

A WP17 torch will do up to 150 amps. A Cheap Chinese one a bit less.

That's nice. I've just bought a Murex WP17 on eBay.

You can use a switch or pedal to control the gas flow.

It comes with a gas valve on the torch body.

Jody at weldingtipsandtricks.com used a big knife switch for a footedal to control the current. I think it was ab battery disconnect for an RV.

Just the kind of thing I was considering.

Plasma is completely different, they run hundreds of volts (my small 25A one says 280V.) They also have complicated arc starting methods.

Oh well ... Never mind.