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  • #16
    TMB: shortest version: your machine has enough juice but it can't get it into the job -- tungsten too small etc. It is being limited by the torch setup. and be anal about the cleaning.

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    • #17
      TMB: one last thing I forgot.... I've never seen a TIG job that needed more than 25 CFH on the gas, and often a lot less. In a non-drafty environment I've been able to go as low as 12 CFH. Back-purging (inside a pipe or vessel) can go as low as 3 CFH. Most of the "fixed" regulators don't give a choice of PSI, they are fixed at around 30 PSI. And the part you get to adjust is the CFH. Really, really expensive (NICE) regulators let you adjust both. Most people just crank them too high though.

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      • #18
        I have done a lot of large part aluminum Tig welding. Repairing destroyed parking lot pole bases, a 3" thick bending die for 4" pipe etc. My go to method is a plumbers lead pot stove that fits on a 20lb propane cylinder. Heat the part until solder melts when you touch it to the part and you are about right. I did quite a few with a 250 amp lincoln IdealArc before I got a 350 amp machine which saved time.

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        • #19
          Mig welds on aluminum are so often seen to done wrong. You need to use spray transfer not short arc like steel. Here's what you need to see and hear. The sound is just like the sound if you are spray painting. If not turn the voltage up. When you stop there should be a sharp point on the wire, not a ball, turn the voltage up. There should be no white powder balls on the floor, turn the voltage up. The weld should not be smokey, turn the voltage up. The ripples in the weld bead should be smooth not sharp edged. It helps to have a helper turning the voltage up initially so you can just run a bead and watch the transition to spray arc. When the settings are right you'll be amazed, and your welding speed goes WAY up, while wire consumption goes down because all the metal goes into the weld.

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          • #20
            Originally posted by garyhlucas View Post
            Mig welds on aluminum are so often seen to done wrong. You need to use spray transfer not short arc like steel. Here's what you need to see and hear. The sound is just like the sound if you are spray painting. If not turn the voltage up. When you stop there should be a sharp point on the wire, not a ball, turn the voltage up. There should be no white powder balls on the floor, turn the voltage up. The weld should not be smokey, turn the voltage up. The ripples in the weld bead should be smooth not sharp edged. It helps to have a helper turning the voltage up initially so you can just run a bead and watch the transition to spray arc. When the settings are right you'll be amazed, and your welding speed goes WAY up, while wire consumption goes down because all the metal goes into the weld.
            I'm going to try a spool gun pretty soon here. It's only on a 210 amp welder, so idk if that will be enough.

            I also had a thought. I read that spray transfer works fine on CC power supplies, and for a while was even preferred... I have a very powerful CC supply. Theoretically, if I just hooked a spoolgun to that (with 24v for the feed I guess?), any reason I couldn't just use that?
            21" Royersford Excelsior CamelBack Drillpress Restoration
            1943 Sidney 16x54 Lathe Restoration

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            • #21
              Originally posted by The Metal Butcher View Post

              I'm going to try a spool gun pretty soon here. It's only on a 210 amp welder, so idk if that will be enough.

              I also had a thought. I read that spray transfer works fine on CC power supplies, and for a while was even preferred... I have a very powerful CC supply. Theoretically, if I just hooked a spoolgun to that (with 24v for the feed I guess?), any reason I couldn't just use that?
              I have seen spool guns driven with a CC supply. It can be done but its fiddly because the voltage floats. Practical upshot is you will only have a set narrow range you can work in. Max the amps out and then find out what the gun wants to feed. Have fixed semi trailers in this way, the gun didn't seem to care how thick it was... we were doing 3/8 plates doubled up. It could blow a hole thru that if I didn't keep moving. No need for a separate 24v power feed for the gun, just take everything from the welding cable. Most stick welders settle down (loaded) in between 24 to 28 volts anyway. Same rules about cleaning the surfaces tho -- soap-water and a brush. I think you'll want DCEN
              Last edited by nickel-city-fab; 03-18-2021, 01:04 AM. Reason: typos, details

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              • #22
                Lanthanated electrodes don't really ball, they just crap out if you attempt to ball them.

                3/32 is definitely too small for >300A AC.
                200A AC is pretty much maximum for lanthanated 3/32"

                For 350A ac I'd look for 5/32" electrodes or even 3/16" (sit before you ask for the 3/16" tungsten price)

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                Location: Helsinki, Finland, Europe

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                • #23
                  You are correct.

                  However, they are my preffered flavor atm and survive for a little while, so 1/8" should do a good while.
                  21" Royersford Excelsior CamelBack Drillpress Restoration
                  1943 Sidney 16x54 Lathe Restoration

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                  • #24
                    Originally posted by nickel-city-fab View Post

                    I have seen spool guns driven with a CC supply. It can be done but its fiddly because the voltage floats. Practical upshot is you will only have a set narrow range you can work in. Max the amps out and then find out what the gun wants to feed. Have fixed semi trailers in this way, the gun didn't seem to care how thick it was... we were doing 3/8 plates doubled up. It could blow a hole thru that if I didn't keep moving. No need for a separate 24v power feed for the gun, just take everything from the welding cable. Most stick welders settle down (loaded) in between 24 to 28 volts anyway. Same rules about cleaning the surfaces tho -- soap-water and a brush. I think you'll want DCEN
                    I tried it out this weekend. I was doing 1/4" plate, and the welder recommended 1 notch down from full output (215 amps). That seemed to burn in fine, and I only screwed one tip getting my wire speed in. I ran it in spray transfer mode, which is a very strange sound for mig indeed. I'd learned a few thing's from Doug Jackson's videos before he went and (didn't) blow him self up. I could try max output like everyone says, but I don't think I was lacking in penetration. I tried on some unbalanced material thickness, but I couldn't stop from melting down the thinner stuff. Everything is just happening way too fast.

                    After re-reading Mr. Lucas's post, I may want to go up that final notch. I did get some black soot build up, but I reckon that is normal. I also did get some of the powder balls, but only when I let my angle get to long and it transitioned to globular (?) transfer.

                    I thought my spoolgun was a cheapie as I couldn't find any brand or model, but after researching it is a LINCOLN - MAGNUM SG, so it should be fine for anything the machine can throw at it. That is good to know. I can't believe we've had that welder for like 6 years and this is my first time welding aluminum with it. Dang!



                    I've also made significant strides on my Tig work. For one I don't get nervous anymore! that's pretty huge as it's hard to do smooth work when you're shaking. I'm now steady enough I can do completely unbraced welding if I have to. I even did a little bit of overhead work. It's also made for a lot less trips to the grinder. I still haven't gotten my 1/8" in yet, but I'm getting along well with the 3/32. It doesn't ball like Matti said, but I just grind a small chamfer on it and give'er the beans. No melting at all under 200 amps. I've also gotten pretty comfortable with rolling into the power quickly like Nickle suggested, wheras previously I was not.

                    I learned something new about the 330A/BP. I thought that the power dial set the power within the range you were in, and the pedal did basically zero to 100% of that. But how could to welder do that? Instead the pedal just goes from 0% of the range to the set value. This is a problem in high range at low percentages. If say I was welding at 30%, I'd hit it full to get the puddle going, then taper off as it was getting hot and then... click! I'd backed off all the way and turned off the contactor. So what I found instead, is that I can generally get away with running in the mid range at 100%, which lets me go down to 30 amps and up to 230, so no issue.

                    I've been preheating the thicker stuff to right at 250F, which makes a world of difference. I absolutely love the McMaster temp crayons. I thought they were overpriced, now I think they are a bargain. I intend to acquire a "full" set in the upcoming years. The largest thickness disparity I did was 1/2" to 0.065" tube. With the preheat, I had no issue, though thankfully it was a smaller piece of 1/2". I've also gotten my helpers to start cleaning parts better which makes a big difference.

                    So yeah. Everything is going well. I thank you all kindly for the advice, it was useful. And if it seemed like I skimmed over your post, I've been coming back to this thread from time to time as I get more experienced. Some of it was over my head at first, now I know enough to comprehend the advice and see how incredibly accurate it was. So thank you all. ❤


                    Not many pictures, I was focusing on my tasks. But here's a few.

                    A few tig welds I am not unhappy with at all. They could be prettier, but I feel confident that they are strong.

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                    The 8 wishbones partially tacked up:

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                    The lower set uses 1/8" wall tubing to account for bending load, the uppers are the 1/16" wall tubing.

                    And finally, the first few inches of Aluminum mig in my life:

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                    I know undercutting isn't recommended, but for this application (and this was a practice piece anyway), I don't care.
                    21" Royersford Excelsior CamelBack Drillpress Restoration
                    1943 Sidney 16x54 Lathe Restoration

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                    • #25
                      Massive improvement! Yea arc time is all it takes... the black stuff, and the powdery stuff, is pure aluminum oxide, now you can make your own lapping grit! Some of it is unavoidable with the MIG, it seems to always happen.

                      On the TIG, yea you have to have a cat's reflexes but be steady at the same time. I always try to rest the butt of my hand, or my "torch elbow" on something. Sometimes you can "hook" your elbow on top of your hip and steady it that way. Welding pipe overhead was a challenge. Keep up the good work!

                      I dunno, maybe I'm used to the speed, the reflexes... usually I have myself and the weld stabilized in less than a second. Kinda like drag racing. It takes practice, and lots of it.

                      I've always set the machine to ~150% of the max the tungsten can take and then just use the foot pedal or knob on the torch. At home my stuff isn't so fancy, no pedal or knob -- just the heat you set on the machine, and scratch-start. I'm not rich enough (yet) for HF at home.

                      The wishbones look OK for a somewhat difficult job (compound angles in all 3 planes... but at least its on a bench instead of overhead. Or crawling up the wall) .

                      Good deal on the temp sticks and cleaning. Those sticks aren't cheap, but they last for years. Good job on the preheating and cleaning. Oh, did I say cleaning? LOL soap-water and stainless brushes for the win.

                      If you really want it to look pretty, I'm not ashamed to "re-flow" over a previous weld with the TIG. Figure you've already got the weld filled in, no need for filler. Just swirl the torch over the existing weld in overlapping circles with a shallow puddle.... comes out looking like a million bucks. LOL just one of my "on-the-job" cheats.

                      Good Job!
                      Last edited by nickel-city-fab; 03-30-2021, 01:50 AM.

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                      • #26
                        Wanted to say, I just *love* spray mode on steel, if the job calls for it, you won't get any better strength than that. Kinda makes a smooth "hissing" sound and looks like a 'cone" of plasma and metal spraying about 1/2" from the end of the wire... one of the recurring jobs at my old job, was to rebuild an impact mill. 1x3x12" MS bars onto a 1/2" thick plate. I used to crank the MIG up to at least 30 volts and 750 on the wire (.035) and you could watch it go like a fire hose penetrating halfway in thru the thickness.... that is where the strength comes from. The 1/2" plate would warp like an old newspaper after the 3rd of 4th rebuild, and was tossed out eventually for a new one. Stock item.

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                        • #27
                          Originally posted by nickel-city-fab View Post
                          Massive improvement! Yea arc time is all it takes... the black stuff, and the powdery stuff, is pure aluminum oxide, now you can make your own lapping grit! Some of it is unavoidable with the MIG, it seems to always happen.

                          On the TIG, yea you have to have a cat's reflexes but be steady at the same time. I always try to rest the butt of my hand, or my "torch elbow" on something. Sometimes you can "hook" your elbow on top of your hip and steady it that way. Welding pipe overhead was a challenge. Keep up the good work!

                          I dunno, maybe I'm used to the speed, the reflexes... usually I have myself and the weld stabilized in less than a second. Kinda like drag racing. It takes practice, and lots of it.

                          I've always set the machine to ~150% of the max the tungsten can take and then just use the foot pedal or knob on the torch. At home my stuff isn't so fancy, no pedal or knob -- just the heat you set on the machine, and scratch-start. I'm not rich enough (yet) for HF at home.

                          The wishbones look OK for a somewhat difficult job (compound angles in all 3 planes... but at least its on a bench instead of overhead. Or crawling up the wall) .

                          Good deal on the temp sticks and cleaning. Those sticks aren't cheap, but they last for years. Good job on the preheating and cleaning. Oh, did I say cleaning? LOL soap-water and stainless brushes for the win.

                          If you really want it to look pretty, I'm not ashamed to "re-flow" over a previous weld with the TIG. Figure you've already got the weld filled in, no need for filler. Just swirl the torch over the existing weld in overlapping circles with a shallow puddle.... comes out looking like a million bucks. LOL just one of my "on-the-job" cheats.

                          Good Job!
                          Thanks Nickle!

                          I'm getting a lot faster on the stabilization. There really isn't any reason I can't roll in fast, just a bad habit from when I was blowing holes in stuff.

                          Well... 330A/BPs are cheap! The HF isn't terribly strong on them, I do a lot of scratch starts as well, especially when the ground is first connected. Works good when hot though.

                          Hard to tell on the wishbones from such a small pic, but no, they aren't beautiful. Once fully welded they should stay together though.

                          I've done the reflow trick some in the past. But, it's not helpful if you're trying to keep the heat down to keep the strength up.

                          Originally posted by nickel-city-fab View Post
                          Wanted to say, I just *love* spray mode on steel, if the job calls for it, you won't get any better strength than that. Kinda makes a smooth "hissing" sound and looks like a 'cone" of plasma and metal spraying about 1/2" from the end of the wire... one of the recurring jobs at my old job, was to rebuild an impact mill. 1x3x12" MS bars onto a 1/2" thick plate. I used to crank the MIG up to at least 30 volts and 750 on the wire (.035) and you could watch it go like a fire hose penetrating halfway in thru the thickness.... that is where the strength comes from. The 1/2" plate would warp like an old newspaper after the 3rd of 4th rebuild, and was tossed out eventually for a new one. Stock item.
                          Oh wow, I didn't know that steel was every spray transferred. I don't think I'll be doing that with Dad's mig. It only does 24V, and I'm usually more of around 300 on the wire. That must have been a big mig!

                          Here was probably the best sample on the spoolgun work. I didn't really get any better after the first one, they all look about the same. It was very late in the day and I was tired though. You can see that I had one very nice little bead where it was in position. I had it clamped to the edge of a bench to keep warping down, and I didn't have access to the back, so I just freehanded those with the gun facing towards me, which of course didn't look the greatest. But all they need to do is be stuck on there, and they are.

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                          21" Royersford Excelsior CamelBack Drillpress Restoration
                          1943 Sidney 16x54 Lathe Restoration

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                          • #28
                            Was gonna say that spray on steel is the easiest thing of all to do. My work MIG isn't actually that big, its just a base model Miller CP-302.

                            I may be wrong about this, but how would heating it more than 1x in a reflow situation hurt the strength? Maybe I just learned something there. Is that an aluminum specific property? I used to do it sometimes on stainless too. I never do reflow on parts where the strength actually matters, its more of a cosmetic thing. If I get it wrong on a "strength" part then I grind back and redo it entirely. I like to see both crazy penetration (welder porn) combined with a really smooth wash-out fillet, with very even ripples. So yah, I'm hard on myself always trying to improve.

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                            • #29
                              Still learning. Starting to get some understanding though.

                              I got these parts of the buggy done. My jig was excellent, but towards the end of the day I was getting tired, so I welded on the end plates with a complete pass with no tacking. Should have tacked all 4 sides and stitched them only. I wanted it to loop pretty tho. So I'll either have to bend them back square or make a fair bit of adjust-ability in the tubes. Previously there was none.


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                              Finish welded:

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                              I did learn an a bit about Tungsten grinding. I had been sanding or grinding my dips off the side instead of snapping it off and starting fresh. Well, I noticed that that made the arc very wide, making it hard to get the rod close without melting it. So that's exactly what I did. I melted some rod, and it dripped off and fell right in my shoe. Youch! Left a nice blister, ruined my sock, and stank to hell. After that I started snapping them off had no more issue. Ok, lesson learned.

                              I also tried a bit of off-hand tig. Didn't go so well, but not terrible. I changed my strategy to avoid doing that. One of my assistants got a really good action shot.

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                              I've gotten much better at rotating the torch in my hand and keeping it at a consistent distance. I've always struggled with the rotation aspect before. Little by little.


                              Lastly some bad news. The tubes in post 12 did not "wick in good". They didn't wick in at all, at least this one didn't. I'm going to have to re-think those entirely after boring the remaining ends out. I'm thinking of leaving them sticking out 1/4-5/16" and doing an external pass with proper pre-heat, then turning them to size. That way I can ensure that there is actually some penetration, not just the filler getting close to the tube.

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                              P.S. The drivetrain holders in the second photo have to be line-bored now. I'm thinking of spinning them in the 4 jaw. 10 1/8" deep bore. I'm gonna need a longer boring bar lol. Alternately clamp them to the cross-slide on the Lagun and truely line-bore them. Wish me luck!
                              21" Royersford Excelsior CamelBack Drillpress Restoration
                              1943 Sidney 16x54 Lathe Restoration

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                              • #30
                                Yep you just found out why most shops won't let you in the door without steel toe leather boots
                                That's really weird about the penetration on that one, I wonder WTF happened?
                                Sometimes it's easier to get the torch right if you hook your first two fingers around the back cap, choking your hold right up next to the torch body. The length of the back cap can give you some "leverage" against the weight and drag of the cables etc. Gives you a fine finger-tip "twitch" level of control. You can get some nice "orbital" motions that way sometimes. Course they make robots that do it nowadays but they *aint* cheap.

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