View Full Version : bending square tubing...

04-30-2006, 07:11 PM
i've got hydraulic benders for tubing/pipe, and i am buying a flatiron hand bender. however, i was talking to an old timer some time ago andwe were discussing bending sqaure tubing. of course, the new fangled way is to use one of them computerized mandrel-specific machines, but he was saying you can also plug one end of the stock, fill it with sand (dry sand- very important), and then plug the other end. use a rose bud and bend using pegs on your table. the sand keeps the short end of the radius from caving in (think extruded patio furniture)....



04-30-2006, 09:11 PM
I tried it with round tubing without the results I wanted, the sand acted like cement & would not move

I think the trick is very little sand not packed in :D

05-01-2006, 02:07 AM
i haven't done it yet, but i think that if you got the long radius hotter than the short side, the metal should stretch...


05-01-2006, 02:11 AM
Yeah I here you

2 torches would be easiest & dotn even heat the one side, just the heat from the others should be enough to anneal it for an easy bend.

Funny you mention this, I was at westec machine show & they had some of the coolest tube benders I ever seen, up to 6" tube tied in knots, square also. They went 20 to 210k Maybe next lifetime :lol:

05-01-2006, 04:08 AM

I've used sand with round tubing several times with pretty good success. I think that square tubing would be more difficult, especially with a short radius bend. Does it have to be bent or can you weld segments together or cut three sides, bend and weld or remove a segment where you have cut three sides and weld? I always use dry silica sand because it has a uniform grain size. I weld a plate or cap on one end, fill the tube and compact the sand by tapping on floor or with a metal object. When you can't get any more sand in weld a plate or cap on the second end. Removal of the dry sand has never been a problem.

I bent the handle on the back my plasma cutter cart using this method.


05-01-2006, 05:08 AM
thanks....i don't have anything cooking right now- i was just seeing what everyone thought...i have the benders for everything but sqaure tube, so after i spoke with that guy i was thinking i'd ask if anyone else had done it,,,,,