Bending tubular sway bar.

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The Artist formerly known as Turbo84
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I'm trying to modify a junkyard rear swaybar (off an old Oldsmobile FWD car) to fit my '69. I need to bend the arms inward a bit more (they're about 15* outward from a right angle, and I need to bend them so they're about 15* inward), but it's a tubular bar (metric, about .600" diameter and .100" wall), and I'm trying to keep from collapsing the tubing at the bend. Looking for suggestions on how to to do this. I've seen guys fill tubing/pipe with sand to keep the bend from collapsing, but I'm upen to any intelligent suggestions. If I'm sucessful with the bend change, I still need to modify the arm lengths and end link terminations.

Thanks for any help.
 
I'll take a stab at this with the understanding that I have never done this. However I have tried to tweak tube bends a little with really poor results.

Suggestion 1: Maybe you could bend 15 degrees (in 2 places) just outside the original bend?

Suggestion 2: If you have access to the inner diameter, maybe you could put a mandrel inside and bend it 30 degrees? I have done this (with smaller tube) and it took a while but worked really well.
 
I tried bending a sway bar, the steel they use is something else. Maybe if you made custom dies for a hydraulic press.
 
ARB Spreadsheet

I've done the "sand trick" on Bimini-top tubing - much thinner wall than I'd expect on an ARB. Worked ~ OK. But a much larger radius of bend I'd expect than you are looking for.

There are kits but are not Junk Yard prices, like 200 bucks but you then pick the length you use. They are all heat treated too, so that might also be an "unbending" issue.

Have you "speced" the size you need? Diameter, wall thickness, etc? Somewhere o an HDD I have a spreadsheet I can look for if needed.

Cheers - Jim

Found It -- Attached! :beer:
 

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Got a bit of excess cabin fever today, so I spent the afternoon at a local u-pullit junkyard, looking for an assortment of goodies, in addition to a swaybar. One conclusion I came to today is that swaybars shaped like three sides of a rectangle are out of vogue these days. Damn near every one I ran into had multiple bends to clear shit, which meant they had more bends getting in the way if I tried to use them on my '69. After a couple hours I did find a couple rear bar candidates under Dodge/Jeep SUVs (acceptable diameter and outside width, but will require arm length/shape changes). I'm going to spend a bit more time under the car this weekend, and then head back to the junkyard next week to pull one out. Junkyard price is $26, so I'll take a gamble.
 
I've done the "sand trick" on Bimini-top tubing - much thinner wall than I'd expect on an ARB. Worked ~ OK. But a much larger radius of bend I'd expect than you are looking for.

There are kits but are not Junk Yard prices, like 200 bucks but you then pick the length you use. They are all heat treated too, so that might also be an "unbending" issue.

Have you "speced" the size you need? Diameter, wall thickness, etc? Somewhere o an HDD I have a spreadsheet I can look for if needed.

Cheers - Jim

Found It -- Attached! :beer:

No, I haven't narrowly spec'd what I need yet, as right now I'm just trying to come up with a configuration that will actually package under my car. Through a bunch of suspension and steering/alignment tweaks I've gotten rid of most of the understeer issues I had when I first put the C4 suspension under my car. But right now, with the f/r weight bias I have (about 52/48) I just need a touch of extra rear roll stiffness to take some of the work and understeer off the front. I'm going to start with a 1/2-9/16" rear bar (because that's similar to the factory rear bar, and that's about all the size/shape of bars I can find that will package with my setup). Once I (eventually) get a bar worked in and some miles on it, I'll have a benchmark so I can see if I need a stiffer or softer setup.
 
I'll take a stab at this with the understanding that I have never done this. However I have tried to tweak tube bends a little with really poor results.

Suggestion 1: Maybe you could bend 15 degrees (in 2 places) just outside the original bend?

Suggestion 2: If you have access to the inner diameter, maybe you could put a mandrel inside and bend it 30 degrees? I have done this (with smaller tube) and it took a while but worked really well.

I understand that in a theoretical sense, but are there places to buy single pieces for small-time guys like me?
 
Well, getting some work done to mount the Dodge SUV rear swaybar. It's narrower than the stock C3 bar (to fit the narrowed C4 suspension), so I had to make a small crossmember to mount the bar pivots/bushings. This crossmember just bolts to the original C3 swaybar mounts under the frame. I just got four small heim joints from McMaster-Carr (damn fast shipping!) to make the links between the bar arms and the suspension knuckle. I'm also making the link brackets for the knuckles, but the time consuming part is the odd shape for them, as they mount under the stock C4 location, due to no room to run the bar arms on top of the knuckle. Once I get the bar and the knuckle brackets mounted, I can then figure out the final arm shape (bend & weld) that I have to come up with to connect the bar ends to the links hanging from the knuckles.
 
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