Ok I know this will sound like a very easy repair, however I am new to this side of things, so I am in unfamiliar territory. I am in the middle of swapping a new axle in my bronco, and need help on new installing new spring pad mounts on the axle tube. I have a Miller 120 volt mig running solid wire with mix gas. I have made small repairs and very minor fabrication pieces, but this is my first run at something that is critical. What tips do the fabricators have for ensuring a good job? Controlling heat? making sure about adequate penatration? I know I will need to bevel the edge on the spring pad so that I get good penetration. Should I run short beads skip some space and then another short bead, and then come back after those have filled and fill in between those beads in order to control heat?And do I need to be careful since the new pad is going on in almost the same location as where the original pad was welded to the axle tube? Could it weaken the tube in that area? I am not planning to beat the snot out of this axle however safety is key! Any help for a newbie welder, wanting to do his own work instead of having to pay to have it done would be greatly appreciated. All have a great weekend and easter!

Chris

Not a guru but no way would I do this task with a 120v machine. I'm not a good enough welder to burn that in with that light of a machine and say it's good. It's too critical of a part. Think about when you lock up the brakes on the pavement at 70... that force goes through those mounts to the springs to the chassis. Bad time for something to let go. I'd get a machine with enough current to burn it in.

*i am not a fabricator, yet, so keep that in mind, but i have taken C level welding course so i do have a little knowledge on it*




id say get a scrap piece, and crank it up. try a few beads and see how it feels. id also try and practice on a couple of junk scraps to get a feel for what you are going to do.

use the bevel, which you already know, and it would be good.

i would try and do a little preheat atleast, just to be safe. run one or 2 beads, and let it sit a few mins to cool, and keep doing that. optimumly, one on one side, one on the other.

thats what i would do with the 120, if that was all i had available, but i would try and prefer to use a larger machine for something with a little more power.

remeber, that is just little advice from the novice, and i am sure the more experienced will chime in if i am off.

heat the pieces with a torch like a hot damn, dont think they need to glow but get that tube real hot. Run a few beads with that thing cranked. Dont worry too much cuz you still have u bolts backing up that weld. I know people that build all kinds of trucks with a 120 volt welders, with preparation they will work ok on stuff like that but I still prefer big power and still pre heat cuz my shit will never break. Breaking parts is ok but breaking Fabbed parts - no excuse

a 120 v welder can lay a pretty decent bead with good pentration, but its all in the PREP WORK, clean everything to a mirror shine, bevel the spring pads, do one side of one pad then do a side on the other pad etc, make sure you have an angle finder thingy so you can make sure the pads are at the same angles.

Just my .02$.

IIRC, dinky little welders like that get more penetration with flux-core wire, don't they? Wonder if that might work a bit better (it certainly won't be as pretty though).

I'd still use (borrow, etc) a bigger machine for axle work.

Change it over to flux core wire or let someone else do it.

Ive welded several spring pertches with my 120 junkbox, and im telling you there is no way you will get adequate penetration on a rear housing with the bottle on that welder. Also, as mentioned earlier, have the housing cleaned down to bare metal at the point you're gonna weld.

exactly. 120v welders have about half the penetration or so with solid core wire. If you preheat the brackets with a MAPP gas torch, you can get good penetration with a 135A welder (extra 1/8" - 1/4" depending on how hot).