Bent Bones

[oldskoolguy]

I have a pair of unmodified 39 merc rear wishbones that I want to use on my T. I will need to bend these out to match my frame. Any of you experienced Bucket builders out there who could offer some advice as to the best way to heat and bend the wishbone castings without breaking them?

 

[donsrods]

Well, you will want to bend the tubes out beyond the end castings. One torch may not be enough even with a rosebud torch, but you can try. Sometimes on something that size you need to use two torches, one on each side, to get it uniformly hot enough to allow a smooth bend. It needs to be cherry red in a pretty wide area, and allowed to cool slowly.

You will need to first make up some sort of jig to clamp the one end to, and some sort of a stop so you can bend one to just the correct place you need,and also to do an exact duplicate for the other side.

The tough part is keeping the hollow tube from collapsing and kinking instead of bending smoothly. That is why so much heat in a broad area is required. You could also pack the hollow tube with sand very tightly and cap up the open end temporarily to help it maintain it's shape. I think that is going to be needed in any case.

Wish I had better info to give you, but those are my thoughts on the subject.

Don

 

[Humidi-T]

I have a pair of unmodified 39 merc rear wishbones that I want to use on my T. I will need to bend these out to match my frame. Any of you experienced Bucket builders out there who could offer some advice as to the best way to heat and bend the wishbone castings without breaking them?

Don't bend the bones. Sell them off and build a set of hairpins or radius rods. If you are going to bend them, definately fill them with sand, as this will reduce crimping of the tubes, and hold the heat so they will cool slower. If you are doing anything more substantial than curving the bones, they may very well become weaker because of the thinning of the metal on the outside radius of the bend and the geometry.

Other than the bending jig, getting them hot, and staying away from the end, the only other thing I would add is you can use a ball peen hammer to find the end of the forging and the beginning of the hollow tube. Just tap from the tube towards the end of the bone, when the sound changes, you are there.

 

["The Bat" out of hell]

There are times some think they have one thing and have another or what ever,plus others read this,so heres a little thing,rear end bones from closed drive shaft cars are week and are not strong enough for open drive shaft use. It's far better to buy or make ,ladder bars,hair pins ,twin torqearms or 4or5 bar set up. Having the rear axle come out under power is as bad as the front axle braking off.
Just a note on the safe side.

 

[oldskoolguy]

Thanks everybody...

These will go up for sale shortly, bought on whim.........rats.

 

[Youngster]

I have been using re-shaped bones/closed driveshaft on the street for a long time and haven't had a failure yet. I would recommend removing the weld in the tubes and rewelding them. I have yet to find one that dosen't have porosity in the factory welds. Bending them behind the tube in the forged area seems to work OK. I don't see this to be any different that heating and bending spindle arms to drop them. You difinitely want to use some kind of swivel end to attach it to the frame ( a tie rod end or Hiem joint ). A bushed end won't give enough travel causing too much torsional stress in the tube. The best setup is to set them up so they attach to the driveshaft tube simular to Henry's design.

With an open driveshaft, You won't be able to phase the U-joints, which will cause them to wear out quickly. If you are building a trditional rod, you might look at the idea of cutting the forging off and welding in a sleve for a nylon bushing and adding an upper arm creating a 4 bar set up of sorts.


Ron

Tip...Cut the front forging off a couple inches behind the factory weld, shape the tube to the axle housing, and you have a cool lower shock mount.

 

["The Bat" out of hell]

Maybe my poor writing was unclear,sorry,if your using a closed drive shaft the bones that come with them are fine and strong enough as long as you keep using a closed drive shaft,what i was trying to say is bones that come with open drive shaft cars/truck are stronger,they are designed that way as the closed drive shaft tube is no longer used as part of what is hepling hold the rear. When you spliting bones,there is a twist that will happen in the bone as the frame rolls to one side or the other,that did not happen when they were center pivoted,this adds to load on them over as they were built,and now we add a lot more load with over extra HP V8's. This is the forces we deal with.
More then a few of us have lifted the front wheels off, and that's super load going on to rear bones or what ever holds rear in place,safe is real good to do. Do I just have a real big right foot.