ratman

how do i back purge, run argon /co2 inside the tube while welding the outside? thx

ham_r_down01

iTrader: (1)

Yes, tape the far end and run an argon purge in the open end, tape around the hose. Make sure you poke a hole in the far end so it pushes the oxygen out. We do it all the time while welding stainless, inconel, ect.

ratman

will the fumes make more hair grow on my chest? or kill me?

gary cook

Not to jump in anybodys bowl of fruit loops of how to do this repair but this is what I do we build custom headers end exhaust so I have I bit of a clue of what im doing some days keep your comments to your self dave haha.
Grind were you are going to repair clean as good you can weather its ceramic or powder or paint it needs to be as clean as possible and if at all possible tig weld not mig you will get a nicer more controlled weld but if you mig remember thin tube it will burn away easy.
Remember the cleaner you get it and the better your fitups are the easyer the job will be have fun good luck.
Also the acid is a good idea we also do that sometimes if we are repairing old dirty stuff make it clean is the key and if you mig don't use flux core wire.

ratman

i have had my mig welder almost 30 years, so im much better with the mig than the tig machine i just bought. i have never needed to weld previously coated headers. the headers are in great condition, just gonna grind off the coating and have at it....thx for your input guys...rm

ham_r_down01

iTrader: (1)

So they are ceramic coated..?? Not alumnized tube..? I'd be positively sure it got ground to base metal before welding. Regardless of the process.

Practice that tig, if I have a choice ill tig it every time.

Cardinal rule with welding, cleanliness is next to godliness.

ratman

i hads some local bozo come over a few days ago to give me some tig lessons... the bonehead could not weld one thing together with the tig... zero, zip... i threw him out in about 20 mins... looking for another guy that tigs everyday to come over and work with me a bit....

ratman

i dont think its a coordination thing with the tig, nothing wants to stick together, i cant get the alum to pool at all when i put some heat to it. i know some of the argon is contaminated here. one guy i know that tigs a lot, hook up every bottle when they deliver it and runs a bead to make sure its good gas or he refuses the tank...

ham_r_down01

iTrader: (1)

http://youtu.be/UNAAhwieNhU This guy makes really good videos. If you get some time check it out.

DO NOT USE ANYTHING CHLORINATED TO CLEAN WITH!!!!!!
Everyone who welds any thing should read this article. http://www.brewracingframes.com/id75.htm


This tubing you are welding is ceramic powder coated(Jet Hot) mild steel? Correct?
You said you couldn't get the aluminum to puddle. Aluminum is welded on a/c high frequency. Mild steel is welded on electrode negative d/c. That may be part of your problem. What wire, size wire, tungsten type, tungsten size, and amperage are you running?

ratman

so far i have tried to tig alum and ss steel. what tungsten do i use for mild steel and what rod. 90% of my welding is mild steel, im building a pro street 48 anglia right now, and will be starting on my pro touring 67 camaro in a couple of months when i import it.... thx, rm