I've just bought a TIG set...

[Cruxi]

...but I'm struggling a bit. I bought it (Murex Tradestig 161is) secondhand and had a little go at the seller's house - with reasonable success (he had done some lovely work with it).
Now I have it at home, I can't get the arc to start. It starts OK if I touch the work and I have done a couple of runs (badly!).

I have the earth clamp in the +ve and I do have the HF start setting on. The only thing I can think is that I am using Argoshield Universal, rather than pure Argon. Would this prevent the arc from starting?

I've fiddled with all the other settings, current, starting current %, gas flow etc.

Any thoughts?

Cheers, Steve

 

[shenion]

You need pure argon, you will contaminate the tungsten very quick with argoshield.

 

[Cruxi]

Argon

Thanks for that Shenion. I had begun to get that impression from reading some other threads. The thing is, do you think that the incorrect gas would prevent the arc from starting?

 

[shenion]

It will probably start once; then the tungsten will quickly get a non-conductive oxide. Probably why you had to scratch start.

 

[fingers99]

I'd not have though so.

Is the HF working?

Any other settings?

 

[snowcat]

Also gaped points on those old transtigs, so moving it may mean it could do with a regap...