Unbending Steel tubbing

[tparker]

I got a new transmission line and it has a 90 degree bend that needs to be unbent. Apparently to be cheaper to ship. Any one have and tips on unbending with out kinking it? I have a handheld tube bender, but I don't think I can get it to unbend. I'll have to double check. Any thoughts?

Tom

[pschlosser]

if it's a wide enough radius, let's say 6-inches or more (think around a 5-gallon bucket) one can straighten it back pretty straight so you cannot tell it was bent.  But if it gets smaller than that, I think it will be pretty hard.

[YellowThumper]

Really depends on how tight the bend is. I have used a hand bender in reverse by inching it around until straight. Also have used a pully as a leverage point.
Best to have sidewalls of tube supported as you are bending.
Do a little at a time.
Plenty of patience required.

[pschlosser]

straightening will likely result in at least some collapse of the tube.  I doubt you can get it perfectly round, again, but even if its slightly oval, it will still function properly.  going slow is the ticket.  trying to bend too much, too fast seems to result in the dreaded kink, despite jigs, coils and support.

[jimynick]

An old school method was to fill the line with a fine silicate sand, full and then carefully bend it straight. The sand supports the tubing and minimizes kinking. If there's fittings on both ends you could also use water as long as you could seal the tube during the operation. My SS brake lines came bent and I just straightened them by hand, so who knows? Good luck! 

[pschlosser]

An old school method was to fill the line with a fine silicate sand, full and then carefully bend it straight.

I've used that method, but for larger pipe, like 1/2-inch conduit.  I would not, if I could help it, introduce sand, dirt or anything into a brake or transmission cooler line

[tparker]

I found a few videos on line after all. They are called shipping bends. Apparently they are easy to do. I watched several videos and all hadd the same basic idea. Just bend it back.

https://www.youtube.com/watch?v=0ke-avFlh8Q

[Racer57]

Call the company and ask what they recommend. I'm sure you wouldn't be the first to call.

[YellowThumper]

No pics of fixture but I made a plate with U shape rollers and bearings. 2 solid mounted and one adjustable.
Bend yours straighter and run it thru. Used mine for coiled SS 3/8 tube.
Made my own but pic is similar that can be purchased.

[Mrbill426]

That's how we used to do it, with fine sand to support it from the inside.

An old school method was to fill the line with a fine silicate sand, full and then carefully bend it straight. The sand supports the tubing and minimizes kinking. If there's fittings on both ends you could also use water as long as you could seal the tube during the operation. My SS brake lines came bent and I just straightened them by hand, so who knows? Good luck!