Bending square tube

[Dirtyrat]

So far I have not used any of the bends much that I made, decided to go another way...
I think the big issue come in with wall thickness versus size of tubing. the inner area of the bend must be strong enough to not collapse when bending.

I'm not sure how well that bender would work on square tubing honestly...

 

[bob w]

I'm anticipating the need to bend square tubing in the near future so all this information is valuable. DR, your approach looks good. Try tacking a piece of gas or tig welding rod to the inside surface, the surface that faces the rotor, and then bend. My understanding is it will push that surface in a bit and keep the other surfaces from bulging.

 

[Todd]

I think the brother-in-law did something like this, making a relief cut that ran along the inside face then welded it up after bending. He said it helped the sides from distorting.

 

[Dirtyrat]

Yea if I get the silly idea in my head on another build where I want curved square tubing, I'll buy a bender... There are a lot of variables that go into whether or not a form will work based on the tubing size, wall thickness, and the radius of the bend... Even with heat, 1" sq tubing with a thin wall can be very trying to bend consistently...

I imagine if I had more room to setup my jig, I would have tried more pieces, but steel aint cheap...

 

[Neverdone]

I have seen a lot of people that use old wheels and rotors to bend and get it to work, I tried it once and gave up..... I started building a blind chicken racing bender and some day when I get a nice shop I will finish that and hopefully my troubles will be over.... But I don't know how that will work for square tubing!

 

[Dirtyrat]

I'd much rather have the tubing roller with square dies so you can work the tubing into shape in multiple passes, vs working it right to shape in one motion...

 

[Artboy]

I built this on the weekend to bend square tubing. Just made it from scraps laying around ( never throw away an old piece of scrap right.??)
Found a piece of old galv pipe that fitted the top of the jack type bender ( lathed the ends flat cause I just bought an old lathe and will find any excuse to use it!), cut an inch wide piece of bigger radius old galv pipe (lathed again cause I can and want to!), cut it in half, welded the half to top of the first piece of pipe, welded some square tube to the sides to act as fences and then bent and welded some small round bar down the centre. To keep the square bar from moving when bending I just used some small pipe that happened to fit the 19mm pins, cut to length(and lathed!) and then jammed it into some square stock that just happened to fit. Practiced on a piece of old square one inch and it worked. Most of what I need are gradual bends that I will do gradually to suit a template but I will try it on some tighter radii also. I think the trick is to do it gradually.

 

[Skip]

Looks good. What does the round stock down the middle do?

 

[Artboy]

Home made di for bending square tube

The round stock folds the inner face in to prevent kinking.