Getting bubles in my TIG beads

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I am a newbie welder, and very new to TIG.  Got a little cracker box stick/TIG so I could work anywhere there is an outlet.  I was practicing with it by welding some 1/8" coupons to 1/4" thick square tubing.  Everything was new and I used a 60 grit flapper wheel to remove everything within 2" of my chalk lines (wax).  Don't know all the terminology, but I had a relatively small cup on the torch - about 1/2" opening, with the tungsten out about 3/8".  The tungsten (1.6mm) was cleaned and sharpened before I started, using a grinding wheel.  Argon was about 23 and I don't remember what current I had the welder set to.  I thought this was going to be a walk in the park, but I kept getting bubbles in my welds.  I did a little searching on the forum for clues and found a couple of clues that might be a good starting point.  I am using 70S-6 filler rods that I got when I got the unit.  This is what the guy at the welding store recommended for a project that involved welding regular steel to stainless.  Somewhere I read that moving to a 70S-2 will make things easier.  Any suggestions?Also, that particular day was especially windy.  I was working in a large barn with doors opened on both sides and the wind was really whistling through.  Enough to make the torch flicker (could've been my imagination).I know my technique needs a lot of work.  I move too slow and I work at the wrong angle most of the time.  I'll work on that, but if there are some physical changes I can make, then this will help.Thank you,Matt
Reply:Originally Posted by mshearneAlso, that particular day was especially windy.  I was working in a large barn with doors opened on both sides and the wind was really whistling through.  Enough to make the torch flicker (could've been my imagination).
Reply:What DSW said.By the way neither ER70S-6 nor ER70S-2 are suitable for dissimilar welds.
Reply:Thank you both.  After reading and researching a little, I came away with the feeling that TIG was not tolerant to any dirt, grease, or disruption of any sort.  These factors are nearly impossible for me to have where I am working.  I can close the barn doors and that will help I'm sure.  I didn't know it was that sensitive.  Am I better off staying with the small cup, or should I move to a larger one?Taz00 - Why do you suppose I was given the 70S-6 rods in the first place?  What kind of rods should I get for using on these barn projects?BYW - The stainless project I had was completed using stick and stainless rods.  This turned out well because of the advice I got on this forum.  Thanks.
Reply:Because they are cheap?Normally I would use 309L rods but if it is a non critical application the ones you have will be fine.
Reply:1/2 cup i/d sounds bigger than an 8 or 9.Start with a "7" size cup if you have it (most common starter cup size) and your gas 15-20. And best results are received when your tungsten stick out is no greater than the i/d of your torch tip. Helps to keep the shielding gas around the weld and tungsten.
Reply:Those cup size numbers represent the ID of the nozzle in 1/16 of an inch.   So a #8 cup has a 1/2" opening (#7 = 7/16, etc.).   When using a standard collet body (as opposed to a gas lens) the general rule of thumb is that the tungsten shouldn't stick out past the end of the cup any further than the diameter of the tungsten.   A 3/8" tungsten stick out using a standard collet and 15 to 20 cfh  probably wouldn't work very well even in dead calm conditions.  Throw in even a little bit of cross breeze or air turbulence in your work area I don't for see that ever working out well for you.
Reply:Thank you, next time I'm in town I'll pick up some more rods and a #7 cup (unless one came in the kit with the welder already).
Reply:if you can pick up a gas lens and an appropriate #7 or #8 gas lens cup, you'll be better off because you can stick the tungsten out further while still getting good argon coverage.  This will help you see the puddle better. 1st on WeldingWeb to have a scrolling sig! HTP Invertig 400HTP Invertig 221HTP ProPulse 300HTP ProPulse 200 x2HTP ProPulse 220MTSHTP Inverarc 200TLP HTP Microcut 875SC
Reply:Originally Posted by 4956When using a standard collet body (as opposed to a gas lens) the general rule of thumb is that the tungsten shouldn't stick out past the end of the cup any further than the diameter of the tungsten.
Reply:Originally Posted by OscarThat's a bit of a stretch.  That would imply that with a 0.040" tungsten you'd only have 0.040" of stick out.  Quite difficult to work with.   Unless you meant "cup" instead of "tungsten" in that last tungsten you wrote.  This I do agree.  3/8" can be a bit much unless someone uses a #10 or #12 cup with increase argon flow.  With a "normal" cup of #6-#8, stickout should be kept under 1/4" for the most part.
Reply:[QUOTE=Oscar;4259941]That's a bit of a stretch.  That would imply that with a 0.040" tungsten you'd only have 0.040" of stick out.  Quite difficult to work with.   Unless you meant "cup" instead of "tungsten" in that last tungsten you wrote.  I am thinking start with 1/2 to 1x the ID of the cup.I can't imagine working with 1/16th stickout. You'd never be able to do a fillet.You can always put up a wind screen, that way the air in the barn can keep moving, but the weld will be protected.Last edited by geezerbill; 06-04-2014 at 09:02 PM.
Reply:Originally Posted by 4956I didn't mis-speak.  That's something I remember reading in an old text book on tig welding.  I agree with you that, that kind of short electrode extension is usually extremely difficult PITA to work with.   I'm pretty sure though that before the development of the gas lens that was kind of the general rule on tungsten stick out.
Reply:Originally Posted by 4956And since you mentioned .040 diameter tungsten (which I've seen a lot of other reference to here on the forums)....what kind of manual tig welding situation is it that you think would require the use of .040 tungsten?
Reply:Originally Posted by duaneb55I think you need to find that old book and reread it.  Be kinda hard to hold a tight arc length and still be able to get the filler rod in there using your book numbers.
Reply:So, which would be better for a novice welding mild steel?  309 or 70S-2?  Or, is this novice not going to be able to tell the difference?
Reply:I'd suggest going with an E70 rod, either S2 or S6 vs 309 for welding mild steel to mild steel. I've seen some guys weld mild with stainless rod at the tech school on occasion ( usually when we ran out of E70 and couldn't get any more from the locked store room). It tends to be "sticky" and is more temperature sensitive than E70. Guys would have issues with getting the rod stuck more than when they used the normal E70 rod. It also causes an "odd" look to the beads that occasionally makes it tough to understand what is going on if you don't realize they grabbed the wrong filler at 1st. It's also a lot more expensive for practice.Having said that I had a friend who welded nothing but stainless. He'd use stainless rod all the time for small projects using mild steel.  Since the projects weren't use critical and all he really needed to do was stick piece A to piece B, there wasn't any problems and it avoided him having to keep an "odd" rod around that someone might be dumb enough to use on a stainless project where it really would matter as far as corrosion..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I've seen silicone bronze rods at TSC.  What are these used for?  Can they be used with TIG?
Reply:There are hundreds of different consumables and base metals but at this point trying them all out will only confuse you not to mention throw away money without purpose.I would suggest you stick to using mild steel rods and metals until you get a feel for the process.
Reply:Lots of good advice.  Stick to what I know and practice, practice, practice....Thank you.