un-bending box section

[finyuk2005]

any tips on unbending box section?
tried it in the press, but 30 tonnes didnt seem to do anything!

maybe need to heat and then use the press?
other than that i wondered about cutting a pie out of 3 sides and welding it back up.

 

[Onoff]

Heat and shove a slightly smaller box down inside. Use as a lever. Push in a bit further, repeat.

 

[skotl]

Is that definitely bent, rather than two pieces offcut and welded together?

To be honest, if it was me and I was happy to bodge it (no significant structural challenges) then I'd slit the outside radius and then re-weld it.

(or bin it and make a new one)

 

[Hitch]

2 blocks of wood underneath, about 300/400mm apart, bend up, and press it. 30 tonnes shod be more than ample. What is it 60mm?

You'd have to take it a fair way past where it needs to stay.
And it'll probably have a little kink in it too.

 

[outofthefire]

I'd just cut and weld it, but you could try running welds down the side nearest the front of the vice, opposite the centre of the bend work out either side of the first weld, grind and repeat till its straight.

 

[finyuk2005]

had another go in the press after tea, i was being stupid before, had it across the press table width wise, or the shorter gap if that makes sense, so i fed it in long ways from the side of the press giving it a larger gap,
this time 10 tonnes was plenty to straighten it,
not the best job but hopefully should do the trick, will go find the tractor and trial fit it now!

cheers for the ideas!

 

[stuvy]

Make another?

Is it worth it???

 

[finyuk2005]

success! needed a little fettle with a BFH but it fits!

 

[Barking Mat]

What is it, just out of curiosity.

And what's it's purpose ?

 

[m_c]

Support leg for something by the looks of it.

 

[finyuk2005]

yeah its a support leg for something along these lines, mounts on the back of the tractor tidies things up nicely after plowing

 

[Alan Reynolds]

I remember when I started mt C&G welding course and mentioned I had an engine crane with a bent leg. The instructor said to bring it in. He produced this thing he called a pepper pot and within seconds the bent section was red hot and it straightened as easily as pvc conduit. Still working over 30 years later.