[danielbuck]

This is a representation of a 3 foot long piece of 1x1" steel square tubing with .065 (1/16") wall thickness, with a gradual 90 degree twist along the length.

Assuming a sturdy jig that holds both ends tight on the inside of the tube and twisting with proper leverage, would the tube just kink somewhere in the middle? Or would you get a gradual twist? Would you need to pack it with sand?

Anyone ever tried something like this before? Not solid bar, but hollow tubing. A gradual twist, not tight twists.

[Otto Nobedder]

I've never tried this. I would suggest, to keep the axis straight, finding a cold-rolled rod that "just" fits inside the square tube (to keep the axis straight as you twist), and cut your piece 3'6", so you have three disposable inches each end to be boogered up by the fixtures you use to twist it. Expect to twist it past 90, as it will spring back when you take the torque off.

This is what I would try first if it were my task, and just a suggestion.

Steve S

[danielbuck]

the metal shop was already closed today, so I'm making two solid pieces that fit in the insides.

Yea I suspect the ends may not be pretty where the dies are in either end.

[Bill Beauregard]

This is a representation of a 3 foot long piece of 1x1" steel square tubing with .065 (1/16") wall thickness, with a gradual 90 degree twist along the length.

Assuming a sturdy jig that holds both ends tight on the inside of the tube and twisting with proper leverage, would the tube just kink somewhere in the middle? Or would you get a gradual twist? Would you need to pack it with sand?

Anyone ever tried something like this before? Not solid bar, but hollow tubing. A gradual twist, not tight twists.

Never on purpose.
Seriously, I might try a piece of pipe with an end welded on offering plenty of leverage and a square hole in it. Were it me I'd weld it to something heavy, make a square wrench to twist the other end. I expect it to bend along with twist unless inside a heavy wall pipe to keep it straight.

[Otto Nobedder]

Actually, Bill offers a reasonable alternative to my suggestion of a rod inside. A pipe who's ID matches the diagonal (ouside) dimension of the square tube would work just as well to keep the axis straight.

You could do both, but that would be overkill...

Steve S

[danielbuck]

Ok, well, it works! I'll post a photo in a bit. But yes, me yanking on a big breaker bar, it's difficult to keep the axis straight up and down. Even dispite that, it's actually a pretty even twist! It's weighted a little bit towards one side, but that's probably because I couldn't keep the axis straight.

I think what I'm going to do is somehow mount it to my JD2 tubing bender, use two sets of roller bearings from an axle, and put a bottle jack on the under-side bearing to keep it inline. Then I can use the ratcheting action and 'gearing' of the bender, it would require alot less force that way, AND possibly the degree wheel. I'll have to look at that and see. I've not yet permanently mounted the tube bender yet (just got it a few weeks ago).

[danielbuck]

Here it is! I used the bumper of my jeep to mount the little bench vice. And a 4 foot piece of fence post (my cheater bar) as leverage on my large crescent wrench. I put clamps on both sides of the tube to keep it from wanting to go round, as my square slugs weren't exactly a tight fit. Now that I know this works, I'll find something solid that's a much tighter fit.

Photos of the twisted tube are after i cut off the ends.

[Otto Nobedder]

Not bad at all!

The axis stayed straighter than I expected with no additional support (My internal rod idea or Bill's external pipe idea).

What's the purpose for this? A decorative touch on a door or gate? Or something more complex?

Inquiring minds want to know...

Steve S

[danielbuck]

Well, it did actually bend/curve slightly, I just leaned on it before I unclamped it, and it straightened out. While yanking on the end of the cheater bar, I had my other hand pressing forward on the head of the wrench, to try and keep it in place. Without doing that, It might have just folded over

It's for furniture. Not exactly sure what just yet, the most obvious thing would be for table legs, or maybe a tall lamp support or something. I more or less just wanted to know if it was possible, now that I know it is, I'll find a use for twisted tube for sure


The last part of this, is a little strange. I want to try putting this twisted tube inside of a round tube, (something cheap, like maybe chain-link fence tubes?) and then BENDING the round tube on a tubing bender with the twisted tube inside of it. I have no idea if that will work or not, the twisted tube may kink a bit? But I'm just exploring, seeing what I can and can't do. I don't have any round tubing dies to try it out just yet, but a friend of mine does, and said I could borrow them if I wanted. Obviously I'd have to carefully cut the fence tubing open to get the square tube out of it. It's just an idea, though I want to try it. I might also try tightly wrapping the twisted tube in maybe some towels or something, and putting that through a tube bender. I don't have as high hopes for that though. I think being inside of a round tube would have a better chance of working.

[Otto Nobedder]

Look through the topic on forge welding.

With a simple propane or natural gas forge, you can make the bends you want by hand, assuming the bends aren't too close to the ends. (Gloves required anyway...)

This borders on art, like glass-blowing, to get "just" what you want, but I'd have suggested this in the first place if I'd though artistic design was the purpose for the twisted tube.

TamJeff's posts can show you designs for hardwood bending jigs (you don't always need dies, even without heat) for the profiles and radii you are after. He does amazing "practical art" for fishing boats.

Steve S

[Bill Beauregard]

Do not bugger up that low rust CJ2-A. I'll get together with all the jealous Vermonters who want it, and beat you within an inch of your life. It's a beauty!

[Braehill]

Daniel,
Have you looked at the Harbor Freight picket twister? Might work for what you're trying to do. I'm not sure if square tubing will fit in place of square stock or not but it might be worth checking out.

Len

[danielbuck]

Just looked it up, I don't know why I didn't think to look up picket twisters.

The HF adapter is for 1/2" pickets, I could make something that would attach my slug to it instead. I'll see if I can come up with something first though.


The jeep I wouldn't call "rust free", floor pans have already been replaced sometime in the passed (fiberglass now, for some reason??) and it's quite full of holes and bondo. But I love it! I normally drive it every day to and from work, but it's parked for a week or so while I wait on parts to rebuilt the passenger steering knuckle that is very wobbly right now.

[Bill Beauregard]

I've had one since 69. Mine is a 47, my first welding project. I cut the body at the seam below the windshield and replaced everything from there back. 45 years later, the paint is starting to look pretty dull. The body is still solid. I used 16 gauge hot rolled, all done with acetylene.