1912 Clamshell issues

[michaelb2296]

Hello,
I have two issues that i ran into after purchasing this 1912 clamshell at Luray, Va.

1. Small crack across rivet hole on the pumpkin not on the torque tube.
2. Brake flange at other end is at .98” depth instead of .8125”

Here are some pics:

After looking at everyones comments here on the forum it sounds like brazing will warp the pumpkin so i should j.b. Weld it and screw it back together and enjoy the ride? The local welding shop even suggested j.b. Weld. Lock-n-stitch says 900F bake then weld (sounds like a devastating warping situation to me.) idk.

As for the outside flange (backing plate) , should i care about 1/8” off??? Whoever started repairing this 1912 clamshell obviously cracked the pumpkin but managed to smash the crap out of the rivets on the outside flange to a point it looks “good ‘nuff” but will the hub be an issue?

Thoughts?
The more i want to jump in the more im thinking its better to drive it than let it sit in a machine shop because of all the things that could go wrong….

[RGould1910]

Ive had a few early (10 -13) rear ends that have been brazed around the rivet holes to stop grease leaks. It was accepted practice years ago. Warping was a common occurance and in my case created a real mess.
If I were you, Id V the crack and use slow setting (regular) JB Weld.
FWIT, I'd also replace the smashed rivets near the backing plate.

[Allan]

The small crack at the rivet hole may well have happened when the rivet was set during initial manufacture. A professional welder should be able to fix it without distorting the housing. It is not an extensive repair. Or, just seal it up and carry on.

The housings in my 1912 van were cracked between four rivet holes, on both housings. Beautifully hand formed crescent shaped reinforcements were riveted over the damage. Welding up those extensive cracks did indeed result in warpage. This required the making of a mandrel on which to mount the welded housings so they could be machined back to true, both the thrust washer facings and the mating surfaces for the axle housing tubes, and then the joints in the centre.

I believe the riveting process to fit the centre castings and the backing plate ends to the axle tubes was a custom fit for each assembly, so mating another casting form a different tube will never result in alignment of the respective rivet holes. Your brake backing plate is evidence of this. When attempting this, it would be easier to weld up the holes in the axle tube and position the casting as it should be, and re-drilling the tube holes using the casting as the template.

Hope this helps,
Allan from down under.

[Dollisdad]

No bigger than the crack is, I would dremmel the crack and mig it shut. You’re not going to get a lot of heat. Media blast the inside pumpkin area, replace all the rivets and coat it with gas tank sealer. Assemble it to be sure the axles are centered in the tube ends. You can then see if you need or want

IMG_9164.jpeg (138.89 KiB) Viewed 1198 times

to move the backing plate.

[Allan]

Just a word of caution on media blasting the housings. I would not do this unless they had been hot tanked to remove all grease residue. Any stuff left in the housings will soak up grit, and it will get through everything. By all means, blast them after tanking so you have clean metal to work with/weld. I suspect Tom's housings went down this pathway.

Allan from down under.

[Jerry VanOoteghem]

If I understand correctly, you have that 1 small crack at one rivet hole? I can't see how that would ever be a problem. As Allan stated, I also believe it's been like that since day one. Why has the rivet been removed?

[michaelb2296]

Where do you find the round (cold rivet) headed bolts to screw the torque tube onto the clamshell housing? I see
Round hex drive bolts but not the others. I guess i could fill the hole with bondo to look round afterwards.

There are other issues with the backing plate needing a repair where the paddle (brake tensioning) bushings are. They are wallowed out holes for sure. They will need welding or brazing shut then reamed.

Would a mig weld fix those or would you have it brazed shut and re-tapped?

[Allan]

Michael, the round head rivet problem is easily fixed. I have replaced all the rivets in my 1912 van axle with 1/4" UNF bolts and nuts. I machined the bolt heads to mimic the rivet heads. Then the threaded end of the bolt is slotted with a hacksaw so a screwdriver can be used to hold the bolt as the nut is tensioned. Nutlock from Loktite will hold the nut in place, and you can always open up the cut slot a little as insurance. It worked really well in 1994, and the axle is still oil tight today.

The bushed brake cam hole is often worn as yours is. A simple fix is to fit a new bush and cam, with a thin washer between the backing plate and the cam.

I have never seen a brake shoe pivot bolt hole flogged out like that! It is a threaded hole to take the bolt, and the nut becomes a locknut when fitted. The hole needs to be filled, drilled and then tapped to take the bolt. You will need to be careful making sure the drilled hole is in the correct position so the brake linings are concentric with the backing plate/brake drum.

Hope this helps, Allan from down under.

[Dollisdad]

You’re right Allan, I forgot about the hot tank step. Very important. Because you can’t blast all the grease out. It needs to be dissolved first. When I did the ones in the picture they were all beaten down like Mikes. I used an air chisel to knock the heads off the outside. Then drove them thru with a drift punch. I left two in place opposite each other to anchor. Then my helper held the housing with a new rivet on the buck, while I used a torch to heat the rivet shaft on the inside till red hot and then mushroomed it with an air hammer. When done, went back and did the two anchors. There’s many ways to get things done. Follow what works for you.

[Erik Barrett]

Early rear end housings are rare for a reason. They are junk and whenever a Ford owner had a problem they were replaced with newer and better parts. So now we have to go to great lengths to repair them and make them work for period correct cars. My solution on these is to replace or reset the rivets and then drill holes into the cavity between the pieces. After steam cleaning the cavity out I inject it with expanding epoxy sealant. After that sets up I put the housings in my lathe and straighten them. All of them are bent.