Splitting a 68 C10 Trailing Arm

[WhiteCST]

I can’t afford an aftermarket tubular arm set and would like to keep my original arms. That said, I have a lot of built up rust inside of the arms and am wondering if anyone has ever split their trailing arms to clean out the inside. How is it done exactly? It appears that I have some rivets that go all the way through and some that don’t. Thanks in advance!

[dondb]

Clean them up as best you can and hit them with an epoxy and paint or some type of rust inhibitor. But before you paint I would tack weld the arms on both sides.

I highly recommend BlackStar rust converter— stops the rust and turns part into a nice patina dark brownish black. Lots of other good options out there as well.

[bubbasimms]

I separated mine...if I remember there were some spot welds to drill out and maybe some rivets. I wire brushed them real good and sand blasted where needed. I then treated the metal with Ospho rust converter and painted them. Then bolted them back together with grade 8 hardware in every place they were originally connected.

[Gromit]

Another option would be to use electrolysis - those electrons can fit in the space between the halves of the trailing arm no problem and will get rid of the rust with no acid residue.

I would submerge the arm in a concrete mixing tub full of water and a half cup of Washing Soda and connect the trailing arm up to the negative clamp of a battery charger. Then the positive clamp to a piece of mild steel approximately the same surface area as the trailing arm.

I use the two amp setting; even for larger parts like this - from the photo I'd say it would take about 8 or 10 hours in the tub - faster if you can position ) the mild steel piece close (1 inch) to the rusty part without risking it touching.

[WhiteCST]

Originally Posted by Gromit

Another option would be to use electrolysis - those electrons can fit in the space between the halves of the trailing arm no problem and will get rid of the rust with no acid residue.

I would submerge the arm in a concrete mixing tub full of water and a half cup of Washing Soda and connect the trailing arm up to the negative clamp of a battery charger. Then the positive clamp to a piece of mild steel approximately the same surface area as the trailing arm.

I use the two amp setting; even for larger parts like this - from the photo I'd say it would take about 8 or 10 hours in the tub - faster if you can position ) the mild steel piece close (1 inch) to the rusty part without risking it touching.

I’ve considered putting them in my electrolysis tank. I have one I’ve made using a large trash can, rebar, and solid core wire. I wasn’t sure how well it would get the large pieces of scale though however. Thank you for the suggestion!

[WhiteCST]

Originally Posted by dondb

Clean them up as best you can and hit them with an epoxy and paint or some type of rust inhibitor. But before you paint I would tack weld the arms on both sides.

This is likely what I’ll do. I have some chassis saver paint from my frame, and I think I’m just going to send it and save for some new arms in the future.

[WhiteCST]

Originally Posted by bubbasimms

I separated mine...if I remember there were some spot welds to drill out and maybe some rivets. I wire brushed them real good and sand blasted where needed. I then treated the metal with Ospho rust converter and painted them. Then bolted them back together with grade 8 hardware in every place they were originally connected.

That definitely sounds like the way to go. I’m not 100% sure where to drill though. I’ve knocked out all of the rivets that go through both sides, but I can’t find anything that looks like a spot weld.

[Grumpy old man]

Why ? if they aren't blistering all you have to do is media blast them and run a few welds and be done with it , Some epoxy prime and paint and your done .

[WhiteCST]

Originally Posted by Grumpy old man

Why ? if they aren't blistering all you have to do is media blast them and run a few welds and be done with it , Some epoxy prime and paint and your done .

I’m mostly just being a cheap skate I’m a college student and am trying to save a few bucks for the next time my 83 breaks down. They aren’t spreading apart, but I’m just not a fan of having rust underneath my paint. Even if it is rust inhibiting paint. That said, I don’t want to ruin them taking them apart, so if I have to save up and have them blasted, that’s what I’ll do.

[Astro-Balls]

Electrolysis, then take to powder coat.

[LockDoc]

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I have taken two sets of them apart, blasted them, painted inside and welded them back together. Drill out the rivets/spot welds and separate them with a chisel. Spray the front mounting bolt bushing with a good penetrating oil and twist the individual halves back and forth to get the penetrating oil worked into the bushing and work them apart. Being from Iowa mine were in a lot worse shape than yours though.

LockDoc

[mcampbell]

My first set off a 72 2WD Blazer fell to pieces as I pounded on them with a hammer to loosen the rust flakes.
I have modified 3 sets of these using Early Classic top and bottom plates. I heard they are a modification for a 3/4 ton.
Clean the old arms then you might even run a bead down the mating surfaces top and bottom. I added that step because I have a couple of 220 welders so no money spent just time.
The plates are about 3/16 steel with holes punched for the U-bolts. They weld on top and bottom and really add a lot of strength to the stock arms.
Price was very reasonable and a bonus is they come with new U bolts and new front pivot bushings.
Might be dreaming and might be the new springs but I think the ride and especially cornering felt tighter with a stronger arm.