A little anti-crater help please

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Well, finally got some gas and been tigging up a storm. Everything seems ok but I keep having craters on aluminum. Don't seem to have the same problems on steel.Tried what the books say and a few other things (filling with more rod, backing off on the pedal, lifting the torch) but I keep getting craters of one size or another just as the arc goes out. Any tips?Thanks,Gary
Reply:I remember one of RockyD's post on the darkside that said mild steel has a tendancy to do that, i forgot the reason though.StangnetShop Full Of Stuff. Joey
Reply:Have you tried stopping then starting an inch ahead and running back into your bead?
Reply:what i do is i will back off the pedal but still hold the arc and puddle and dip, dip dip that seems to work the best for  me...... also remember that the heat travels so quickly with the aluminum  by the time your at the end you might have just melted it away dawg
Reply:Are you sure you got all the oxides off first?  Scotchbrite pads on a whizzy wheel followed by an acetone wipe work wonders.  And that should be done within 2-4 hours of welding, depending upon the cleanliness of your shop environment.  Also recommend 4043 filler rod, if you aren't already using it.
Reply:Thanks guys, I got it figured out by moving the torch in a cirlce as I backed off the pedal. Seems to work OK as long as I feed in rod at the same time. The trick is to not end up with the rod frozen in the puddle. I'm using 4043 and clean the oxides just before welding then wipe with acetone. I would think the AC would clean them up anyway during welding. Am I wrong?Tried starting an inch down and backing into the weld. Just ended up with a crater there instead.OlPilot.....you claim 2024 can't be welded? I've read it can't many places but I've also read it can by using 4145 filler. Any comments? I have a cracked gear door on my L39 I need to repair. It's non-structual. How about brazing?
Reply:My boss used to ride me pretty hard when I welded aluminum.  At the end of a TIG weld, if you weren't careful, you would leave an @sshole(as he would put it).  The only way I can put it without showing you is after your at the end of your weld and done with your filler, either let off the juice slowly or if you don't have a pedal, do a swirl and pull away as you cut the juice.Common sense in an uncommon degree is what the world calls wisdom.