I borrowed my Dad's tig and decided I'd check it still worked after transporting it. So cleaned the tungsten ran a 2.5inch bead on a piece of scrap 1mm didn't blow a hole, so then decided to run one with filler rod seemed to go ok didn't touch the tungsten off the metal or the rod. So I decided to try a butt weld on some semi cleaned up zintec I cut in two. After each tack I had to clean the tungsten despite not touching the piece and although a ran a pretty neat bead for an inch I managed to blow a hole as I wasn't in a good position and stopped. It seemed like the bead ran ok with the zintec although definitely not a clean weld. Would me lifting up slightly at the end of the weld cause the tungsten to contaminate or just the zintec on it's own? I found the tig so much neater and easier than my mig for 1mm and even though this was my first tig weld it seems much more controllable than mig (for the bits I got the puddle going on anyway).
- Thread starter 1960bus
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Tom Orrow L
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TIG doesn't take nicely to "nastiness" on metal. I believe Zintec is cold rolled mild steel with a layer on zinc on it so its probably the zinc burning up and causing unclean weld & the tungsten contamination.
I don't know if giving it a run over with a flap discs & wiping it down with acetone would work but it might be worth a try if that is all you've got knocking about for practice.
The only thing that lifting up slightly at the end might do is leave a small crater at the end of your pass.
I don't know if giving it a run over with a flap discs & wiping it down with acetone would work but it might be worth a try if that is all you've got knocking about for practice.
The only thing that lifting up slightly at the end might do is leave a small crater at the end of your pass.
It's the zinc coating boiling off. Zintec can be TIG welded without constantly contaminating the tungsten but you can't hang about and obviously zinc fume isn't very healthy. Removing the zinc coating locally with a clean 'n strip disc makes it nicer to weld, something like CR4 saves messing about and is much nicer to work with from a shaping POV too
I'll get some cr4 and try that. I like the zintec because it's easier to store without flash rust. I didn't get any cratering until I reached the end I could see it starting to burn back so I stuck the rod in the pool which worked although I got it a bit hot but I don't think that was a crater from contaminants.
