Distortion problem

[eggster71]

Hiya,
I'm using 80x80x3mm box section to build replacement heater channels (big bloody sills) for my offroad VW beetle.

With a 30x30x3mm addition on the side to take the outer bodywork.

The problem is that over the space of a metre I've discovered 10mm distortion,
roughly shown here:

I'm thinking ( I have MIG and ARC sets) Of running some heavy beads across the "inside" face of the box section (where the measurement in the above photo was tahen) to attempt to pull it back into shape. Does anyone have any thoughts on this?
I don't have acces to oxy acetylene which would be the obvious weapon of choice.
Cheers,
Simon

 

[rtbcomp]

I've used carbon arc electrodes to heat metal to bend it.

What I did find was that I couldn't get a good arc directly to the metal, but I ran a weld bead where I wanted to bend and used the carbon arc on that.

 

[eggster71]

Cheers for the reply. Tried everything to straighten it but ended up clearancing the mounting holes. Seeing as I'm not fitting a specifically shaped part I think I should get away with it!