im making up a turbo manifold at the moment,when i come to weld the runners can the argo/co2 from my mig welder be used for backpurging and what effects does it have

 

Not unless you have PERFECT fit up, basically if your joints can't hold water the c02 will contaminate your weld, same thing with nitrogen. Your best bet is to just run pure argon.

 

i have argon for the tig welder only single outlet regulator though,just thought the mig welding gas would help when backpurging,i was going to use masking tape on the joints i wasnt welding to save losing all the gas

 

what he's saying is that the co2 thats in mig gas is actually a contaminate for tig welding
youre better off not back purging than using 75/25 to back purge


and you can always put a t after the regulator and maybe even a needle valve to control flow

 

purge with argon, co2 is simply going to break down in the weld and contaminate the **** out of it

 

thanks ,ive been to get a twin outlet regulator

 

twin regulators on a T i bought from central welding. i was describing what i wanted and he said they didnt carry it, we looked in books till he found what i was talking about and he put the number in the computer, turned out they had a few in stock but had never seen em.



the T was 30-40 bucks and the on off valve was prolly 10 or something (blue handle kinda angled funny)