Welding on Axle Tubes

[james j]

Hi Guys!
I'm a little new here, but I am finally getting back to my project. I'm have a '68 charger and am putting the spring relocation kit coupled with mini-tubs.  While I have the new spring pockets are already installed in the frame rails, I have the new leaf spring perches just tacked in place on the rear end (which still has its axles in it). As such, I just wanted to see if you have any advice on how to finish the welds on new perches. I figure that it would be easier to ask, since I am concerned about warping. The rear end still has it's original axles in it, but they will be replaced before they go back in the car.

Any hints or advice would be greatly appreciated.

Thanks,

James

[c00nhunterjoe]

I have not had warpage problems welding on my rears. Be sure to check your pinion angle before welding the perches

[John_Kunkel]

 
Lots of folks come on these forums and claim if you weld it "correctly" you won't get any housing warpage. I wonder if they actually checked the housing with a full-length jig rod. Any welding I've ever done, including simple perch relocation, resulted in noticeable housing warp.

[ws23rt]

^^^I'm with John on this.  Any welding task will result is some "warping" as well as induced stresses.
This is why in most fabrications that require welding --the welding is done as soon as possible in the process. Stress relieving and final machining follow.

An example of a case where a final (critical weld) was needed on a job I was working and final alignment needed to maintained.---It was an eighteen inch HP steam connection from a steam turbine.
I was monitoring the turbine movement at the drive coupling with dial indicators.  The welder and I communicated at every inch of tig weld root pass.

The welder made the first one inch of weld and I told him which way the coupling alignment moved. We then decided where the next weld needed to be to counter what we saw happen.

It was impressive to me what the expansion from the heat of welding (just a one inch root pass) did to such a large piece of machinery. The contraction that followed a short weld pulled it out of alignment and our task was to guess at the next best place to weld needed to bring it back to spec.

This process went on for many hours until the weld was finished. We both knew that we were just making sure the final stresses from welding were balancing out each other.

I've been a welder of all kinds for nearly forty years and this experience stays with me. Just thought I would share it.

BTW when working in a proto type fab shop for 7 years as a welder of one off stuff it was a constant battle predicting and fighting the movements caused by welding.

My advice for the OP is to have all the parts where they need to be and make several tack welds that oppose each other. Stop and make sure things are still where they should be. Continue adding weld a little at a time in opposite locations. This should work out fine.

If one were to just start welding heavy passes where it's easy to reach it could call for unanticipated grinding and or shimming to follow.

[RallyeMike]

You can keep sheet metal from distorting if you go slowly enough and keep the heat down. Warpage, if any, will be less the original tolerances of Chrysler's manufactured unit I'm sure.

[six-tee-nine]

I bought a Dana 60 for my 69 recently. The guy I bought it from got it from under a drag car so he rewelded the perches back in the stock location.
I already wondered why the axles were not mounted in the tubes, because he dialed in a new ring and pinion kit and installed new bearings. did'nt take me long to find out....

Trust me, its not because its no sheelmetal it wont deform. metal tubing warps easily. I guess its perfectly possible to spot weld them in place.
Some people tend to believe that when you weld without stopping that stuff is stronger, but i tell you is you do that on one of these axle tubes you're screwed.

[skip68]

I sometimes do shorter welds and a spray bottle of water to cool.  You don't have to have one continuous weld.   

[james j]

Thanks Skip. Have you had any issues with the tubes warping or excessive bearing wear?  Thanks!

[skip68]

I'm talking in general for avoiding warping.  I have welded an axle once and also welded a perch for springs on an RV.   I just took my time and did short welds and water to keep it from getting warped.   

[ws23rt]

Some things to be mindful of about welding.

When the metal is heated by the arc or flame it will expand in that area. Visualize a flat bar that is heated on one edge.--It will get longer on that edge and gain a curve. As it cools it will contract back to --about-- where it was before the heat.

In the same example when weld metal is added to that heated area that extra metal will have it's own added contraction as it cools along with the bar. This added shrinking force will tend to pull the bar into an opposite curve.

This is a very general description but is helpful in predicting where a part will end up after a weld.

Welding on sheet metal panels can be tougher to control because the very soft metal (in the heated area) tends to be randomly pushed/mushed  around by the surrounding contracting area.

Much control over warping can be had by keeping in mind what the metal will do as it heats and cools.

[John_Kunkel]

I'm talking in general for avoiding warping.  I have welded an axle once and also welded a perch for springs on an RV.   I just took my time and did short welds and water to keep it from getting warped.   

OK, not trying to be a jerk, but did you actually check the housing alignment with a full-width jig bar after welding?

[skip68]

No I didn't.   It didn't seem to need is far as I thought and I don't have a jig.    I just did small spots and let it cool.   I did the same routine on my son's buggy axle for fear of it warping.   Everyone has their own method and limitations.  One can do it without trouble and another might mess it up.   Best thing to do is if in doubt have someone else do it.   I'm not a professional welder by trade, but have done quite a bit.    

[ws23rt]

No I didn't.   It didn't seem to need is far as I thought and I don't have a jig.    I jus did small spots and let it cool.   I did the same routine on my son's buggy axle for fear of it warping.   Everyone has their own method and limitations.  One can do it without trouble and another might mess it up.   Best thing to do is if in doubt have someone else do it.   I'm not a professional welder by trade, but have done quite a bit.    

 Skip you are like most of us. We like doing stuff for ourselves and even if it doesn't always work out as hoped we gain for the next time.
I learned about left hand threads by breaking three off on one wheel before a friend helped me with the other two.

Learning from others is helpful but learning for ourselves is a lasting adventure.
I will also add ----If fear of screwing something up is too great we are not gear heads and miss a lot of good fun.  I always gained value and memories from what went wrong.

[skip68]

I know.  I've always figured since I have the tools I'd better learn how to use them.   I've warped enough 1/4 inch steel to know how to get it right.  
Years ago when I bought my first wire feed welder (Lincoln) I would still have my buddy help me with welding.      I got a Miller a few years ago and love that machine.  Now I don't care what it is that needs welding I'll do it myself.   I actually enjoy it.  Unless I'm welding upside down.      
I'd honestly be more concerned with getting all the measurements right than warping the tubes.  Because I'll take my time with 1" welds and not overheat it.   

[six-tee-nine]

Problem with this is that lots of less expierienced people tend to think that the material is thick enough and they go full steam ahead.

[John_Kunkel]

Everyone has their own method and limitations.  One can do it without trouble and another might mess it up.  

That's where we disagree, I used to narrow housings and respline axles. Trust me, without a jig you probably warped them but not enough to notice by eyeball.

[skip68]

From just welding on perches?    Obviously you have by far more experience with axles then I do John.  I'm sure you're right.    
Listen to John James and play it safe.    Like I said I've done it but not an expert.