Stainless Tubing Bender

drewpster

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Oct 17, 2006
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2,059
Every now and then I re-post this question to see if anyone has come up with an easy way to bend handrails. I have looked in to some benders that look like they could handle the pipe, but I have found none of them that have a provision for bending finished, or polished pipe. I have also looked in to having them made but geeesh its expensive. I would be willing to drop some cash into a tool I am sure to use in the future, or sell later. ($100 or less) Has anyone attempted it using a heavy conduit bender? I have a small conduit bender I bought from a friend because it was cheap. But honestly don?t think it is going to do it. Especially without marring that expensive polished pipe. Any thoughts?
My handrails are aluminum, I want to go back with stainless.
 

Bob_VT

Moderator & Unofficial iBoats Historian
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May 19, 2001
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26,084
Re: Stainless Tubing Bender

I do quite a bit with SS and I really like it. Most of it comes coated with a plastic coating ....so why couldn't you coat the pipe/tube with tape?

Stainless steal takes very well to polishing too
 

Woodonglass

Supreme Mariner
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Dec 29, 2009
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25,930
Re: Stainless Tubing Bender

Well, I have never bent Stainless but... I WOULD try to tape it with duct tape, fill it with sand, seal the ends and give it a go with a normal conduit bender.

I'm just sayin...:D
 

fstorm08

Senior Chief Petty Officer
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Aug 2, 2010
Messages
686
Re: Stainless Tubing Bender

Thanks for the suggestions. :)

At some point, I'm going to need to get a new piece of railing and put a little bend in it as well. :D
 

D.spencer

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Sep 5, 2008
Messages
200
Re: Stainless Tubing Bender

Those real nice smooth bends you see are usually made from hydo-forming. a high pressure liquid is pumped into the pipe and it is bent around a mandrel that is been highly polished that will keep it from collapsing. I might suggest the sand but use extremely fine ashtray sand or aquarium very fine sand OR/ use a oxy/acty torch, heat it up-not too much and bend it around your own mandrel that has the shape you want-a piece of wood should work. it will be blue at the heating point but it can be polished back
 

Coho Ghost

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Feb 26, 2010
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Re: Stainless Tubing Bender

Don't want to step on anyone's toes here, but do not use heat, especially red hot heat, to bend 300 series stainless steel.

I would think you are using type 316 stainless tubing. It can only be cold worked. High heat will cause it to rupture and tear at the highest stress points in the bend.

Someone correct me if I am wrong here.

Coho Ghost
 

Mark42

Fleet Admiral
Joined
Oct 8, 2003
Messages
9,334
Re: Stainless Tubing Bender

304 soft temper (annealed) will work well. Easy to bend, a plain old conduit bender will work, and no heat needed. 304 will resist corrosion very well, but you can always upgrade to 316 if you want.
 

archbuilder

Vice Admiral
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Sep 12, 2009
Messages
5,697
Re: Stainless Tubing Bender

I bent my stainless rub rail around a tight corner by heating it. The problem was that it laid over as it made the corner, so the top needed to be shorter than the bottom. I heated it the carefully bent/hammered it around a red oak jig I made till I got it right. After that I wet sanded it from 120 to 2000 and polished. Turned out a lot better than I thought. The tubing challenge will be of course to keep it from collapsing....or kinking. I have heard of people bending steel tube around jigs by filling them with sand, "corking" the ends heating then bending. The IMPORTANT part was that the sand was dry, otherwise it explodes from the water turning to steam! It seems like without supporting the inside of the tube, it will be almost impossible to bend. Mild steel conduit is a lot more ductile than most stainless. I'm not sure that was much help, but maybe it will give someone an idea.
 
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