The Stovebolt Site Forums The Shop Area Engine Shop Anyone Used Mig for Rear Spring Perches?

On my 56, PO had set up the rear axle and tacked the spring perches in place. Not knowing any better, I cranked up my Lincoln 135 Mig and welded the rest along the outside of the tubes. I've driven the truck for a couple hundred miles or so, and all appears fine and dandy. After doing some reading, I see that perhaps my Mig welding was not a good idea. I now have a Hobart 235 220V spark box and am wondering if I should augment my Mig welds? Or should I even worry about it at all, since everything seems to be holding fine?

I did on mine, same welder as you have. I don't give it a second thought, the u-bolts are what hold it together. Joe

My Dana 70HD had the perches welded from the factory with a MIG welder, and I am sure of it, as I took a tour of the factory.

I cut them off and moved them, used a stick welder because that's what I had at the time, no problems.

I have also TIG welded some on someone else's axle, again, no problems.

If using the MIG be sure you have good penetration, and some of the smaller machines may not give it to you?

Grigg

Clint,

As Grigg pointed out, material thickness to be welded is usually limited by the 'oink' of the machine...the maximum output in amps, and type of wire used.

If your MIG had instructions with it, take a look at them. I just bought a little Lincoln 140C and it tops out on 5/16" material...and this is with flux core.

A 135 amp machine might be hard pressed to properly weld a thick spring perch to a heavy walled axle tube. The welder not only melts the filler wire, it must also melt some of the parent material so all that soup can joint together as one.

I'm sure your job is OK, but for general info, this is how it sort of works.

Stuart

Any of the welding processes should be adequate if properly done the reason some people steer away from MIG in structural situations is it is easy for the novas welder to get a good looking weld that isn’t really very good at all. Pay real close attention to the point that the weld bead meets the parent material it should flow in to the parent material at a very light angle without dipping below. The weld bead should be a slight raise above the parent material about 1/8 it’s thickness on ¼” material.
Identifying a good clean weld with proper penetration takes some practice, in welding school you have to make countless welds that the instructors will pull / cut apart and analyze with you not only to sharpen your welding skills but to also make sure you can tell a quality weld from a poor one.
No matter what the process used to make the weld it should be as strong as or stronger than the parent material, when pulled apart the weld should not be the point of failure.
If you are questioning your welding ability get a good instructional book and some scrap pieces of metal like that you will be welding on most and practice compare you welds to those pictured in the book and then using whatever method you may have pull it and cut it apart and see what you get, practice makes perfect.
You can even take short classes at your local technical school or community collage and have a lot of fun doing so; DIY is a lot of fun especially if you can do it better than the pros.

I think the welds are probably OK. I made multiple passes with the highest amperage setting. I used the same setting and process welding a hook to my tractor bucket which has supported V8's and yanked everything from t-posts to power poles with no sign of breaking. I also used the same setting to repair the upper shock attach fitting on the rear where it is riveted to the frame crossmember and had fractured. I know I got very good penetration there. My spring perches appear to be 1/8-5/32 metal. Essentially, you have a T weld on each outside surface where it meets the axle tube. As I said, I made multiple passes, building up a 1/4 to 3/8" radius fillet.

All that being said, if I ever have to do this again, I'll use the 220V Stick Welder.

All I use is my Mig welder since it's all I have. I have done several spring pads & have never had a problem. Just be sure you have good penetration and everything will be fine...Joe

I prefer the stick to the mig but the mig held up good enough that I peeled open the axle tube on my pickup.... but even though the weld didn't give up I did the next one with my stick.