Welding Tips and Tricks

hello everyone
first time posting here so first of all thank you jody for this exelant site and forum, learned alot.

sorry in advance, i dont know how to explain in short.....
im from israel and have been welding with tig mostly stainless steel. from time to time i welded some aluminum mostly up to 3 mm. in the past months i've beed taking on more and more aluminum welding jobs.
the last job was welding 15 mm plate to 3 mm wall tubing and 5 mm suports.

im using a kemppi 2300 mls ac/dc
to max my machine capability i welded on 95% en. 50 Hz sinus wave. #5 cup with about 10 l/m or 20 cfh.
after tacking i welded the suports to the tubing first to let the metal soak heat but when i went on to weld the plate to the suports the plate was still not hot inough and the first bead was full pedal, verry slow, somewhat narrow and not as concaved as the following beads. also it had a very dull appearance compared with the others.

to those who lasted.....
1) is there an advice u can give on how to make all the beads shiny??? (the far bead in the pic is the first one)
2)because of the 15 mm plate i had to weld most of the way on 230 amp or i'll get llitle or no puddle, i focused the arc on the plate but my concern is the metalurgic properties of the tubbing not knowing if i dameged it or not. any advice there???

btw the gaps in the plate were designed that way which didnt make my life easy.........
thanks for the incredible patiance.
Eran

Those look pretty good. As for the shiny part of it, I would say it's not enough cleaning action. That's from my experience and my opinion. I don't do a ton of AL and unfortunately (somewhat) I don't have too many problems so I can't provide too much troubleshooting.

If you have access to a cylindet of helium to mix with your argon you will achieve a hotter arc and puddle so you can weld easier and also be able to introduce more cleaning action. Jody shows how to do this and there is plenty of discussion on the forum too. Search helium.

It sure looks like you know what you're doing. It's hard to tell from the pics but those welds are very nice and I don't think anyone would complain about a lack of shine. If that was my work, I would call it a day and walk away happy.

Looks like a pretty good job to me. Are all of the pieces made of the same alloy?

big gear head wrote:Looks like a pretty good job to me. Are all of the pieces made of the same alloy?

thank you all for your answers.
the plate and the suports are 6061 and the tubing is 6063.

my welder is vary borderline on this thick aluminum so i'll probably go for a 350amp one.

Coldman wrote:If you have access to a cylindet of helium to mix with your argon you will achieve a hotter arc and puddle so you can weld easier and also be able to introduce more cleaning action. Jody shows how to do this and there is plenty of discussion on the forum too. Search helium.

i bought a small cylinder filled with 75% he and 25% ar and had some trouble with it, something just doesnt work.
there are a few types of helium grade here in israel and its usage for welding is very rare so there wasnt anyone who can tell me which kind i need.
people never use it because its very expansive in relation to argon. i think that the cost is less relavant if it gets u beter results especialy like pentration. the price to fill a 300cf is today about 240$ which i think is a rip off but thats the way it is.
same tank size in argon goes here for 65$ to 80$.

i will try to get the specs for the helim types here maybe than you cold say which tipe/grade is good.
thanks

If thats US dollars,it is within 10% of what pay in MPLS, MN 55407.Lots of creative price gouging every where.

rick9345 wrote:If thats US dollars,it is within 10% of what pay in MPLS, MN 55407.Lots of creative price gouging every where.

for argon its ok. but helium 240$ a tank??? i figuerd it has to be atleast double than argon but not 240. well If its the same over where you are than i must be mistaken........

That's a good looking weld especially given the ridiculous material thickness miss-match - I'd be happy if it was me though we all want perfection! only real solutions I've seen work would be preheat the 15mm with a propane torch to start with or as others have said add helium - it really does make that much difference - I agree cost is stupidly high ( maybe due to how much Len & Steve waste ! ) I have a half size bottle & blend a bit when needed but it's tricky getting a consistent mix ratio - if you are going to do more ally work I would invest in a proper mix bottle - BUT not 75 he / 25 ar - some welders will run this but most really won't - once you get up even to 50 / 50 the arc will be hard to start & erratic when welding - if it were me I'd try to find some 25 he / 75 ar - this will usually run great on any welder - puddle seems cleaner / wets out well / mostly leaves less surface erosion - on the subject of shiny beads if your using 4043 filler & a lot of heat it always goes dull for me - if you can source an alternative that is acceptable to the client I'd try it - the new Maxal wire gets talked about here with great results but I'm not sure it's available outside the US of A - I never found any so far - best of luck with the welding - can we ask what is this part that requires such a thick base on such thin tube ? also unless it's just for looks it would probably weld easier using Mig.

thanks for the tip noddybrian. ill try 75% ar/ 25% he i hope it will work. btw i used 5356 filler wire
i dont know what the part is for, it a welding job i do for a big fab shop, they work with the big name companies so i didnt ask.
i get about 5% of the welding jobs they have, they do almost all themselvs but give me the ones they dont have the time or know how to do.
this part is part of the job also. two posts and two bended tubes attach to some kind of arc.
im working on a new project now, stainless steel part, big run,its 2 mm wall thicknes eccept the machinin in the middle, there it 0.6mm . i wanted i big cup for my #20 but no luck.... nowhere in israel.
for now im using a #7 cup.
gonna get me some furic cups that i've seen some of the welders here use and have awsome results......

any way thank you all its nice to have an input from proffesionals and realy learn.

Here's an earlier post I made on helium grades / problems ;

http://forum.weldingtipsandtricks.com/v ... 171#p71344

My .02c is that the balloon grade helium could be filming the tungsten. When we were using pure helium ( from memory it was welding grade 99.998% purity ) with a Syncrowave 350 on AC, it would film the ball and you had to sort of scratch start; wipe the ball on the part and hit the pedal when you were lifting. With a fresh tungsten, no problem. And if you have any 2% thoriated, use that.

http://askzephyr.com/what-are-the-diffe ... -used-for/

Try grinding it clean, also up the flow rate to around 40-45 cfh on an argon meter. It was always my understanding that only welding grade helium should be used. If you do get a puddle, you will probably get, at best , a very sooty weld.

I respectfully disagree that 40 > 45 CFH is ever needed when Tig welding - generally high flows will cause turbulence problems not give better shielding & if we are talking measuring Helium flow on one calibrated for Argon then absolutely NO !

If I misread your meaning - sorry in advance.

Cup sizes available to fit a small torch you should find No.10 fairly easily - probably 12 in specialist stuff - sure it's a wait on postage but they can be ordered online & posted virtually anywhere.

That was using straight helium with an argon flowmeter, as we were waiting for helium meter.

The rep who advised the ratio increase ( 2.5 to 3 X ) was formerly a welder at Lockheed Marietta and we had no problems.

I have noticed that when I use certain filler wire it dulls the appearance of my beads on aluminum. They most shiny beads I get are when I have a lap joint or corner joint that does not require filler wire. But some wires are better than others as far as bead appearance. I am welding on 4043 mostly.

To me, it looks like the parts may be a bit too cold while welding. Preheating thick material before welding can help the beads shine more (and/or use a bit more amperage when welding) .The thick material may be sucking too much heat out of the weld puddle immediately after you move forward, allowing the weld bead to cool too quickly. Notice how the bead looks even duller/hazier at the start of the weld when the material is coldest:

When I weld thick material, I'll start the puddle and wait several seconds before adding filler rod and moving forward. This gives the material some time to heat up.