critique my aluminum welds please

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been doing bead welding for about a daytrying to do some lap/butt/t joint weld... is there a trick for doing the t joint? Some reason I'm just blowing thru them. Htp221 120amp 65% Bal 180 freq 3/32 2% ceriated tung on the Pyrex cup.  3/32 4042 filler
Reply:How thick is the aluminum? It looks like you need to turn the amperage up a little, you want to get a puddle started quick and get moving. If you look at the start of the beads, you can see the large etched area where you had to sit and wait for the puddle. That makes it a little harder to control the puddle when you get going because the aluminum has already started getting saturated with heat.Other than that it looks like you are doing good with the beads, but need to work on the craters at the end. Back off the amperage slowly and add a little extra filler to keep from getting crater cracks.With the T joint, I think your problem was low amperage. Because of the joint there was allot more aluminum you had to heat before forming a puddle. From the picture, it looks to be near 1/8", if that's about right then you will want to use around 150 amps or up to around 175 (depends on the joint/size) to get the bead started. Back down the amperage as needed when the puddle gets too large.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Use enough amps to puddle in 3 seconds or less - then get moving and back amps down as needed.If it takes longer than 3 seconds you are saturating your piece with heat and that will make it hard to control heat during welding.Like squirmy said, 150+ amps for a quick start on 1/8" aluminum.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Thanks guys, yea didn't know there was a rule of 3sec or less. Makes sense cuz I do sit on it for a while to wait for the puddle to form. It is a 1/8thick al. I'll try it again at a higher amp tomorrow as I get more Al scap.
Reply:The 3 sec rule is what I go by, but I likely stole it from someone else at some point On thin stainless it's more of a one second rule from what Jody said in a recent video.Good luck and burn lots o rod - this is a very long learning process - but it's worth it.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.