proper TIG technique - HAVE MERCY ON A NEWBIE!

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Man, I'm having a rough time with my inside fillets.  Material = 0.125" Aluminum (5052).  Setup: TA 185 (Inverter, AC, Squarewave) 150 Hz, 150 Amps, Thoriated Tungsten (3/32).My question - when I'm trying to get the two edges to meet & flow should I be rocking the torch back & forth, or just moving it up & down.  In other words, should I be twisting my wrist back & forth in a fan-like fashion?  Or just keeping the angle consistent & move my arm up & down to "stitch" the two sides together?   And a follow up question - to what extent can I hope to just fuse these together without filler?  This isn't a structural weldment - strictly decorative.I plan to post some pics soon, but you guys don't even want to see the mess I've made so far....tx!Hobart BetaMig 1800Esab Handy Plasma 550TA Pro-Wave 185 TSW
Reply:I'm definitely a rookie too so don't pay too much attention to what I say.  I've been having trouble with fillet welds too.  I'd say that you want to just move your hand up and down and keep the angle constant.  When we get better we should be able to just run straight down the piece and get it.  You may end up having to do a couple of covering passes to get it just right.  I'd think that you would be better off using the filler rod instead of just fusing the metal.  I think it would look better seeing as it is decorative.  One other thing.  You might want to try a pure tungsten tip.  That is what I have been taught in class to use for aluminum.  Although I have seen someone here say that the 2% thoriated should be used for advanced squarewave.  I'm going to stick with the pure (green) tungsten for the moment though.
Reply:Well Ive been welding a while, but my tig is not that thorough,  so bare with me but I think I can still help you with what I know.  First of all you are asking a question to folks that you really need to ask yourself.  However, I also understand the feeling of not making real great welds and thinking that if you could change your technique youd automatically make better welds.  First of all thats not true.  But at the same time heres some tips.  For one, with aluminum in particular use your filler rod.  This will help prevent cracking particularly at the end of your weld.  I don't quite remember the name of this, star cracks seem to ring a bell but its been a while for me.  What it is mostly is where you get a crater  most certainly at the end of your weld.  From that crater it cracks and once a crack starts the whole weld breaks.  So for starts use a filler rod,  not necessarily the whole joint, but for most definately the very end.  Next is while your actually welding what I would do is to use a circular motion with your cup.  Sometimes the C motion with the open end of the C going forward.  Othertimes a box works, or even an oval.  It all depends on the puddle though.  On aluminum and V-groove Tig I like the C motion.  This is because you can heat up the sides prior to the puddle moving in.  You should speed your motion up as you reach the open section of the C, and slow down as your in your puddle.  This allows you to heat up the sides of your joint without getting a puddle established and yet you keep the C small enough your puddle is shielded and it just keeps running.  This for me seems to work.  Most new heli-arc'rs I know like to use circular motion though.  I think it makes it easy for them.  Most important is try differnt things.  A good welder will use differnt weaves depending on how the puddle moves.  The way a puddle moves will vary becuase of position, material, thickness and sometimes joint design.  I hope this helps you out.  A lot of guys swear by a certain weave pattern,  I think its all just personal prefernce.   Just find find something comfortable that you can control you heat and your puddle.  Good luckCHRIS
Reply:declan,am i correct in assuming that you are having problems getting the vertical and horizontal pieces to wet at the start of the weld?if so, a couple of suggestions:1)  make sure the material is clean just prior to welding.  a stainless wire brush and acetone should do the job.2)  the pieces could be welded without filler but for a first timer it's going to be difficult to get a nice bead without a lot of undercut.  the filet will be very shallow.  also, a little trick i use to get the initial flow going is to feed in a little rod just as the two sides start to melt.  with the ta 185 you should be able to get a nice tight bead, but i suspect that you will be adding filler rod until you get the hang of recognizing manipulating the puddle.  btw, i don't like the thoriated electrodes for this work.  i use the 3/32 lanthanted sharpened to a point.  practice, practice and practice ---
Reply:you dont really want to use the "fan motion" you want it to be i nice angle so keep it that way and just practice practice practice
Reply:Thanks for all the input.  I burnt through the one electrode that came with the machine and should be receiving a new pack (1.5% Lanthanated) tomorrow.  I figure it's just a matter of practice, so that's exactly what I plan to do!  thanks again - I'll post pics soon.Hobart BetaMig 1800Esab Handy Plasma 550TA Pro-Wave 185 TSW
Reply:I just got shown Millers Tig Handbook plenty of handy info in there you might like