Tack stainless

[rkde]

Hi guys,

Its seams less normal that I actually ask a question but here we go,

I have just purchased all the lovely 304L stainless steel to make an exhaust system, I plan to tig it all off the car and I am not worried about that, however I do not really want to be tigging under the car for tack welds.

I would like to know if I can use my MIG which has a good mild steel grade wire in and argonlite in to tack it up.

As I sit here an think about it I am sure this will give a rusty weld in time to come even if I linish it back... Have I answered my own question here?

Can I tack it with the MIG?
Should I just tack it with the TIG?

OR is there something better I can use to pin it together as my TIG set is currently not near the car. Maybe mark it up and walk it to the workshop tack it and try it on the car?

Suggestions - think the heat is getting to me

 

[Hitch]

The Mig with the correct gas and wire would be alright, you could fettle the tack away before Tigging it up to get a decent looking weld.

But steel wire, and argoshield light, isn't really the right consumables.
Wasting your money if you go down this route imo.

 

[madkayaker]

The weld will rut and most likely contaminate after it has been ground out, I would either ur TIG to tick it or get proper wire ns ga for the mig

 

[wheresmejumper]

recessing the tungsten in the cup,and resting the cup on the pipe,works well for consistent tacking.

 

[rkde]

Thanks all for confirming my thoughts. I will just drag the tig out and do it.

My last tig job on a car was welding an alloy gearbox lug back on under the car and I hated it as there was no room. Maybe this time it will be different...

 

[hotrodder]

OR is there something better I can use to pin it together as my TIG set is currently not near the car. Maybe mark it up and walk it to the workshop tack it and try it on the car?

Suggestions - think the heat is getting to me

Unless i have use of a car lift (rare) i normally usually use a variation on the above... mock it up in sections using tape/modified jubilee clips/homemade clamps* with witness lines as a back up for any joints that are a PITA to clamp securely.


* some examples

 

[Lawnmowerboy]

I believe it was langy or hotrodder that said when people ask about stainless wire for tacking up with the mig on an exhaust. He said to use a normal mig and mild wire and gas and grind the tacks out after?

 

[langy]

You can tack with normal mig wire and grind off but its far easier to use 2" masking tape around the joint and then tig in the bench, another method is to use stainless wire and a wide exhaust clamp with a hole in it, just tack through the hole

 

[rkde]

Cheers guys. Let's hope out goes well this weekend...