Hi everyone so been practicing for a few days and I'm still getting really poor welds. I'm running c25 @20scfm and 0.025 wire. I'm practicing on 23 gauge donor car metal (which I cleaned both sides) and trying to do butt welds. Machine is a Lincoln 175 @220. I'm using Cooper sheets in the back with some heavy Earth magnets to line up the metal and prevent heat warpage. I'm stitch welding one for at a time and moving to another party of the coupon.
Machine says to use a2 settings, I have done that and gone up on the wire speed and even tried b setting. I'm keeping the gun as close as possible, trying to stay less then or closer to a quarter inch. I'm angling the gun about 10-15%. Still getting crappy welds. The last image shows my last line, not getting penetration on the back and the arch seems pretty violent. Occasionally I get a good weld and it sounds perfect and smooth, but not most of the time. What should I start focusing on?
Last run below not penetration on the back. Cooper stop does the back side
IMAG2226.jpg (73.8 KiB) Viewed 1875 times
IMAG2225.jpg (86.14 KiB) Viewed 1875 times
Previous run no penetration on back on the final lines
Thin gage can be tricky but you have done right goin for 0.025 wire. Skip the magnets, will disturb the arc if close so you'll struggle getting the heat where you want it.
I usually run very short bursts when patching cars, rather like tacking but overlapping. That way you can crank up the amps to get penetration without burning away the edges.
Also check your cable connections and make sure they are well tightened and have good contact. Bad ground can mess up your welds.
I am clamping directly to the test pieces. So its possible that the earth magnets I am using are causing interference with the arch (they are very strong), I guess that somewhat makes sense.
Also I could be pulling too much heat using the heat sink I conjured up, I'll give all these changes a try.
Literally looking to tack piece by piece perfectly. I am working on a lower fender so I want to be perfect before I start on that. I have seen a bunch of youtube video and it seems that when guys are stitching they hold the gun at all different angles. Since I am tacking, I shouldn't have to pull or push the molten puddle right? Its a quick zap and stop.
A car friend told me that the way to do it is to do one small bit, maybe two zaps with the welder and then leave it to cool completely. It's takes ages and it's frustrating but you need to manage the heat input and distortion
Not sure which one, but Jody has a vid explaining distortion in thin pieces. The gist of it was that slower welds have a wider heat affected zone, hotter, faster welds have a narrower heat affected zone.
I think you need to crank it up a bit and go in hot and fast, dont dally around. Do short hot fast beads.
It looks like the beads you ran out of the joint worked better. Sort of like tightening bolts to JUST before they strip
Run your bead at the point JUST before it burns a hole, then move.
Try this approach: 12” long piece. One hot tack at either end. One in the middle. Then, divide each 4” section in half with another tack. Then divide each 2” section with another tack. Rinse and repeat. Moving several inches after each tack minimizes the distortion, reduces the overall heat soak, and lets you reposition. Connect the 1/2” tacks with short beads, skipping several inches between them. (Weld 1/2” and the move 3” and weld the next 1/2” section). It will take longer to weld, but save you heaps of time on grinding and bodywork.
Try this approach: 12” long piece. One hot tack at either end. One in the middle. Then, divide each 4” section in half with another tack. Then divide each 2” section with another tack. Rinse and repeat. Moving several inches after each tack minimizes the distortion, reduces the overall heat soak, and lets you reposition. Connect the 1/2” tacks with short beads, skipping several inches between them. (Weld 1/2” and the move 3” and weld the next 1/2” section). It will take longer to weld, but save you heaps of time on grinding and bodywork.
Try this approach: 12” long piece. One hot tack at either end. One in the middle. Then, divide each 4” section in half with another tack. Then divide each 2” section with another tack. Rinse and repeat. Moving several inches after each tack minimizes the distortion, reduces the overall heat soak, and lets you reposition. Connect the 1/2” tacks with short beads, skipping several inches between them. (Weld 1/2” and the move 3” and weld the next 1/2” section). It will take longer to weld, but save you heaps of time on grinding and bodywork.
Not sure that math works
In re-reading, you’re right. But cut me a bit of slack. Was up at 3:00am to fly to FL for the day, then flew home at 12:00am. After 21 hours and a few drinkers, sitting in an airport trying to think with all the commotion, it got away from me. Point is: divide and conquer (no matter how you add it up)
Most newer vehicles are completely hot dipped so the zinc soaks right in I've had the best luck with hot fast tacks work up and down as far apart as you can back and forth about every two inches they should almost be counter sunk most cars are spot welded from new keep in mind you'll have to grind anything above the panel so hot clean short welds are the best also place the lower panels over the uppers so as not to create a pocket in the back for condensation keep at it
I agree with others, skip the magnets. Even welding magnets messed with my arc, I'd imagine a rare earth magnet is even worse. The welding magnet being within an inch or two messed up the weld, so a rare earth magnet could affect the weld in a larger area?
Lincoln Weld-Pak 180
Lincoln spool gun
Everlast PowerUltra 205p
AHP AlphaTig 200X
Assorted stuff
I'm purely an amateur so take it with a grain of salt but I set my Miller 211, one step hotter than the actual metal calls for so, if I'm welding 20 gauge, I set if for 18, then I just spot weld and cool. I leave a gap the thickness of the wire between the butt weld ends too.
I never stitch because it distorts and burns through.
I've had the best luck with hot fast tacks work up and down as far apart as you can back and forth about every two inches
Quade wrote:
I never stitch because it distorts and burns through.
Try a push angle. Having the wired feed ahead of you can help with thin material welding, and uphill MIG. Essentially you are throwing more wire onto the area that is heating up, before it’s hot enough to blow out. Sort of.
Adding filler to the puddle always cools the puddle. With a push angle, you're throwing cold wire onto a puddle edge that is getting hot, where with a drag angle you're adding filler to a puddle that is hot. It's a technique for helping with thin gauge to prevent blow-outs.
