andyb64
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| posted on 24/3/06 at 10:11 PM |
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Wanted : Tig Welding Tuition
Hi, I'm looking for a welder/fabricator in the Leeds area to give me a couple of evenings worth of Tig welding lessons. I have all the kit and
have done some Tig welding but feel I could do with someone who knows what they are doing to give me some pointers.
Alternatively if anyone knows of any evening classes local to me. The only one I could find was 3 hours a week for 26 weeks and I don't really
need a C&G in welding.
Anybody out there able to help.
Cheers
Andy...
[Edited on 24/3/06 by andyb64]
[Edited on 24/3/06 by andyb64]
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ed_crouch
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| posted on 25/3/06 at 04:10 AM |
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Well, Im hardly an expert in TIG, only having done a couple of weeks worth ( fulltime training course), but the big hitters I found were:
DC Electrode Negative for steel, AC for ally. DCEN puts about 70% of the heat into the metal, so the tungsten doesnt melt. AC puts 50% heat into both
the metal and the tungsten, which is why the Tungsten balls up on AC. The AC blows oxides away from the parent metal (some kind of electrolysis i
think), Thats why you use AC on Aluminium.
Red tag tungsten electrode for steel, white tagged for ally.
Choose an electrode of roughly the same diameter as the parent metal thickness
Its easier with a footpedal to control the amps
If you manage to dip the tungsten into the pool, STOP! Clean and regrind the electrode. dont try to carry on, it'll look sh1t and will fail.
Careful regrinding the electrodes, cos Tungsten is very brittle... and expensive! Ideally you would grind them on a diamond wheel, rather than
carborundum.
remember to hold the torch over the end of the weld until the gas shuts off. This is to protect the very reactive aluminium from oxidising deep into
the joint whilst its still hot.
Phew!
Ed.
P.S. there are probably pro TIGers round here who are more knowledgeable than me though!
I-iii-iii-iii-ts ME!
Hurrah.
www.wings-and-wheels.net
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