Steel bending

   / Steel bending #11  
I have got some rectangular tubing that I need to bend a tight radius. It is 1x2x.125 Rectangular tube. I need to bend four pieces that are 30 inches long. The image below shows two of the pieces as they will appear finished. Wondering what would be the best way to bend something like this. I would like to do it myself, I did phone some machine shops and they wanted a lot of money. Any suggestions would be appreciated.

View attachment 310193

Very tight radius you are attempting to bend. Won't say it's impossible, you'll need to experiment to see just how tight a radius you can accomplish.
Bends like this are usually accomplished by mandrel bending.
You can "approximate" the mandrel bending process at home by filling the tube to be bent with molten lead (melt down a car battery or two). Lead is way better than sand.
The lead can be removed by simple heating the tubing.

Cerrobend is better than lead, but costs $15.00 - $20.00 a pound.

Make a jig on your shop press or rig a hydraulic cylinder to essentially emulate a press break. It's going to take substantial pressure to bend the tubing.

Another method is enclosing the tube by welding the ends shut, on one end fit it with a 3/8" hex socket screw or pipe plug.
Fill the tubing with water, screw in the plug and bend. The pipe can also be frozen to increase the internal pressure, being careful not to burst the tubing.

Please let us know how you make out.
 
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   / Steel bending
  • Thread Starter
#12  
Bending the tube was purely cosmetic, but I'm thinking that I'm going to lean more to cutting and then welding it. But you have given me some really good suggestions. I've attached two renderings of what the difference would be, I've just always been a little picky about how things look as well as how functional they are.

It was 107° bend with a 1 inch radius. Really tight.

CUT.JPGbend.JPG
 
   / Steel bending #13  
Bending the tube was purely cosmetic, but I'm thinking that I'm going to lean more to cutting and then welding it. But you have given me some really good suggestions. I've attached two renderings of what the difference would be, I've just always been a little picky about how things look as well as how functional they are.

It was 107° bend with a 1 inch radius. Really tight.

View attachment 310305View attachment 310306

If weight is not a problem, 1"x2" flat bar stock would bend nicely to the radius you desire.
 
   / Steel bending #14  


If you make 6 cuts over 2-1/2" (1/2" apart) each about 0.2" wide at the inside of the wedge (mark each at 1/8" and cut outside the marks with an 0.040 cutoff wheel will get you pretty close to that), you'll have a pretty close approximation...and you won't have to hold the metal in place like you would if you did a cut-and-flip.
 
   / Steel bending #15  
Sand workquite well in most cases, but if the piece to be bent is short enough I'v found that filling it with water and freezing solid works better tha sand without resulting in a concave area on the inside of bend.
 
   / Steel bending #17  
He could just use two of those side by side...
 
 
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