AboutEd Kerr Expertise I can answer questions about TIG,MIG and Stick welding, Oxy fuel and Plasma cutting. The affects welding and heat have on certain metals. Materials you can and cannot weld. What to do and not to do on pressure vessel and pipe repairs.
Experience 22 years Aviation and aerospace tooling and equipment fabrication, welding and repair. Aircraft airframe welding and repair. Welding exotic metals and alloys.Marine Aluminum and Stainless steel welding and fabrication. General welding and fabrication.
Education/Credentials H.S diploma
Awards and Honors American Welding Society Welding code certifications
Military Spec welding procedures and qualifications
Question QUESTION: Hi Ed, I have tig welded 6061-t6 aluminum quite a few times now. I always use 4043 rod. I am told this rod is good for vibration and strong, I know there is stronger rod but not good in vibration situations but stronger like 5356. My question is I just read online that when you weld 6061-t6 temper the area at the weld will loose 80% of it's strength. I read you can retemper piece to bring the whole part back to temper and strength. But can I do something different Ed to help me in the future for this? Is there a way I can bring temper back myself without buying some kind of big expensive equipment or maybe I should be using different rod? All your thoughts would be greatly appreciated Ed. Thanks.
ANSWER: Hi, 80% seems high to me. It will definitely become softer in the heat affected zone, but I don't think it will lose much strength. To be honest I think if your careful not to over heat the part, you won't lose enough strength to be worried about. I would stick with the 4043 filler, try to weld as cold as possible and the largest diameter filler you can get away with. A trick I use when I don't want to over heat a part is to use the pedal to manipulate the puddle, for example when I add filler I give it more heat then back off about 20-30% then so on. Be careful not to leave any voids though. It really depends on the thickness,size and weight of the part your welding,so it might take some practice. Let me know if you have any more questions.
Ed Kerr
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QUESTION: Ed I like to use 1/8 electrode all the time. I seem to weld aluminum from 1/8 to 3/8" thk. If I could do you think I should step up to a 3/16" electrode. Just to make the electrode last longer in the high heat situations. Even if I am welding a 1/8 thk piece does it really matter if the electrode is 3/16" long as the amperage is right going thru for the part?
ANSWER: I use to not give much thought about tungsten diameter, But it is important to use the right size for different jobs. Now I use the smallest diameter I can get away with, I'm using .020" in my rig right now, and it really helps to keep the appropriate size puddle, in this case the engineer is calling for a .040 fillet on a stainless weldment, and the smaller tungsten rally helps. When welding Aluminum 1/8" tungsten does, like you say cover allot of material and weld sizes. Last week I was welding some real thick stuff, 3/4"x6" I used a 1/8" pure tungsten in a #18 wet rig and a 2 to 1 Argon-Helium mixture. With a slight pre heat the 1/8" held up nicely, the Helium allows the use of the smaller tungsten,if you don't use it, you should. I strongly suggest using the right size and quality Tungsten for each job, you might be presently surprised. Lets say your welding 1/8" Aluminum material and the drawing calls out a 1/8" fillet, its going to be difficult to achieve such a small weld with an 1/8" Tungsten. Plus the extra heat needed to establish a puddle that big will really start to cook the part. With a smaller Tungsten you have much more control. But if you have some real thick material to weld, try 5/32" first 3/16" is huge! I also use the largest diameter filler rod I can get away with, this works for me, you might want to try it.
Ed Kerr
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QUESTION: Ed thanks for all the tips, just one last question. Since I am not a welding shop I want to keep my setup as universal as possible. I use straight argon right now. I like that argon, helium mixture. If I switch to that could I still weld steel and stainless steel with that mixture? Would there be anything I couldnt weld with that mixture? And would I really see a difference in welding with that mixture compared to the argon? What would I see?
Answer Hi, I mix my own gas, its simple and the ratios are infinite. When you don't need helium for your next job, you just shut off the Helium side of the splitter and the bottle. All you need is a regulater/flow meter for the Helium bottle, a "Y" gas fitting(splitter) and 2 18" gas lines(the green stuff).I never buy Argon/Helium premixed. Another thing, don't buy a cheap flow meter, get the glass/ball type, the dial guages suck, you don't have the control and leaks are undetectable. A big Yes, you will see a big differnce when using a spot of Helium. First off its a little louder, and more intense of an Arc, and the heat is all there. The puddle will be real shiny and clean, as will your tungsten when you break off. I only use it on Aluminum 3/8" and thicker. If you want more you just turn it up, if less....... Don't forget to turn your A/C balance from CLEAN to DIG or penentrate(if you have it).Any ? please ask,
