Rolling steel tube

[gib]

Sand doesn't really work, its hard to pack it in the tube and get it packed in there with enough force to be dense enough to work. If you can pack it in at minimum you have to cap the end to keep in in there and not flow out the ends when you try and bend the tube.
I just bent some thin aluminum tube with cerrobend alloy. It work very well. It has a low melting point, I believe around 150f. Melt it pour it in bend it re-melt it and pour it out and your done. I put vegetable oil in the tube to keep the cerrobend alloy from sticking to the inner wall of the tube. The aluminum tube I just bent was 3/8 diameter with an .028 thk wall. I bent it with a 1/2" radius tube bender that I made. There is no way to make that small of a radius in a tube of this nature without spending a bunch of money or finding a specialist to do it. http://csalloys.com/products-cerrobend-alloy.html Take a look at the link and see if this would work for your application.

[Mike S]

Cerrobend----------haven't heard of that stuff for 40+ years.

When I worked at Garrett/AirResearch, we used to use it to support the blades when machining turbine wheels, many unsupported blades would get a resonate vibration from the cutting tool.

[gib]

Up until recently I haven't use cerrobend in 20 years. I used it to bend the small diameter tube just a few weeks ago. The forming department at work saw me using it and they are going to try it on something similar to what you were using it for Mike S. If I am not mistaken Garrett (Honeywell) does not allow the use of Cerrobend anymore.

[Mike S]

Originally Posted by gib

If I am not mistaken Garrett (Honeywell) does not allow the use of Cerrobend anymore.

They probably dont have any more of these old beasts anymore either.

[gib]

I don't think they have to much of that kind of stuff anymore Mike. At least not the places I go to in Honeywell. I do have a picture of the tube I bent. I was wrong when I said it was a 3/8 diameter, it is a 5/16 diameter tube.

[flynwest]

I have a hossfeld mandrel bender that will work. I think the smallest radius die I have is 6". If you have a sprint car shop around they use them for the nerf bars.