cleaning/replacing tig nozzle

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Hey,When welding Al (1/8" 6063 with 3/32" 5356 filler) I have gotten a glaze on the inside of one edge of the #6 cup that I think is either Al or a combination of Al and Tn.  On one unhappy occasion the arc seemed to be jumping from the electrode to this glaze inside the nozzle, and then arcing from the edge of the cup to the work.  After shutdown the edge of the cup where the arc was forming was glowing red hot...  Continued use with a sharpened electrode had arc going where it was supposed to, but bad porosity and sugar coating issues, that I have not yet figured out.Under magnification it looks to me like Al is getting deposited on the inside of the cup and I have no idea how to remove it - stuck on there like something that is really really stuckon there.  Have not tried any kind of magic scraper.  (like a thin knife)I suspect that this happened from my dipping the electrode  into the puddle (I call this afoxtrot yankee moment) or occasionally hitting the needle with the filler.  So my questions:Is it plausible that this thing (the cup) is just unusable with this coating on it?Any sane way to clean it up?When do you replace a tig cup?  ( I've seen some vids of actually pretty good folks that havea truly horrible looking nozzle in terms of what I think is Al spatter growing all over the business end.)When you contaminate a needle, can you just grind off all the obvious Al and resharpen or shouldyou cut off some amount of the thing (I saw 1/2" on some site) and then resharpen?Thanks,m
Reply:as far as the cup goes if it is ceramic you can bead blast it to remove any deposits. I do this regularly, makes them like new again.for tungsten, any inclusions must be removed, by what ever means it takes.sounds like you are dipping your tungsten, or welding much too dirty material if you are getting deposits that badwhat tungsten are you using? make sure it is thick enough, pure tungsten is what I'd use, 3/32 @ 17-20cfhLast edited by sausage450r; 07-19-2014 at 03:30 AM.'14 HTP invertig 221Thermal Arc 201ts'15 HTP 2400'13 Hypertherm Powermax 30Esab 875Esab 251Clark Metal Servicespecializing in stainless steel exhaust systems
Reply:I think you're right on the dipping tungsten and dirty metal.  I tried a fresh unopened bag of filler and got better results by far.  Examining the old and fresh filler under a glassshows old stuff to be dingy looking - Don't know how to clean it really - degrease and brush presumably but brushing small dia. round stuff has me stumped.  Tried scotch britebut didn't help really.Also replaced the back cap which I had dropped.  It cracked the front part of the thing in a way I thought wouldn't matter but the new cap seems to help.  Not sure,chasing ghosts at this point.  Sometimes works, othertimes look like no kidding lava, so I file it and start over.I'm using 2% Lanth. tungsten from Amplify by way of Arc-zone by way of China.  3/32.  m
Reply:Originally Posted by mman Examining the old and fresh filler under a glass shows old stuff to be dingy looking - Don't know how to clean it really - degrease and brush presumably but brushing small dia. round stuff has me stumped.  Tried scotch britebut didn't help really.
Reply:Hey,Yeah, I tried alcohol and acetone and then did the scotch brite, either something else (like me) is broken or no help there.Maybe the scotch brite is leaving junk on the filler.I'd like to change my original question:Does anyone know the best paint to cover up porosity in Al welds?  Shiny aluminium color and preferably radio opaque.Thanks,m
Reply:HAHAHAHAHAhahahahaaa: popcorn:SqWave 200Millermatic 190Airco 200 ACHypertherm PM45Boice-Crane Band SawVictor O/A
Reply:Originally Posted by mmanI'd like to change my original question:Does anyone know the best paint to cover up porosity in Al welds?  Shiny aluminium color and preferably radio opaque.Thanks,m
Reply:Originally Posted by mmanHey,Yeah, I tried alcohol and acetone and then did the scotch brite, either something else (like me) is broken or no help there.Maybe the scotch brite is leaving junk on the filler.I'd like to change my original question:Does anyone know the best paint to cover up porosity in Al welds?  Shiny aluminium color and preferably radio opaque.Thanks,m
Reply:Originally Posted by mmanHey,Yeah, I tried alcohol and acetone and then did the scotch brite, either something else (like me) is broken or no help there.Maybe the scotch brite is leaving junk on the filler.I'd like to change my original question:Does anyone know the best paint to cover up porosity in Al welds?  Shiny aluminium color and preferably radio opaque.Thanks,m
Reply:Originally Posted by MinnesotaDaveCover porosity with paint??  ......um, what??Cut, or grind, it out and do it again......must work for a trailer company or Harbor Freight tools......
Reply:OK, some results in hopes it helps someone.Problem was occasional (like 2 out of 3) welds really ugly and various bad things happening on 6063 with 5653 filler.Also same result on 6061 test coupons with same filler.Looked at each of:  - cup contamination (arcing from contaminated electrode to contaminated cup to work)  - filler contamination  - leaky torch / gas path - Testing this was a bother - have to seal it with electrode in place and look for bubbles...  - crumby metal (the part) from the far side of Mercury  - suspect electrodes  - sabotage from evil racoons Real problem was a combination of  - leaky torch (maybe kind of a long shot, but did help some - new aft teflon gasket (where leak was) and new back cap)  - crudded up filler metal and  - a foot pedal that was possessed - it would randomly disengage the rack from the control pot so you'd never get to full heat,or you'd never come back from full down or (this one finally got even my attention) just run HF and no real arc at all.  Don't knowhow it was interacting with upslope/downslope.  Basura.  New pedal and other stuff above seems to have done the trick.  The job is a 2x1.5x1 Al block of 6061 slapped up against the side of a 6063 angle forming a cantilevered mounting lug.  (Has to support a human jumping up and down.)  Anyway thanks for the help.Regards,m