Straightening front bumper

[wrndln]

I have a 28/29 front bumper (both bars) that are bowed inward about 1/2" in the middle. The bars have been rechromed so I don't want to damage the plating. I believe the bars are made of spring steel, so it seems like they would tend to return to the original position easily, so they would need to be "over" bend it seems. Has anyone found a way to straighten front bumpers?
Thanks for any useful suggestions

 

[John Duden]

You can adjust the bumper hangers so they pull back, if you do it correctly it will straighten it, that’s what I did with my 28

 

[Tom Wesenberg]

i separated the 2 bars and supported the on 4 x 4's at the outer curves, then jumped on each bar until it was straight across. This was on a nicely replated front bumper. Too bad it now went through the fire.

 

[jw hash]

I`m with john on this one. your front bumper irons, if the ends are bent wrong they can pull the center of the bumper in or out, and it does not take much to do it.

 

[Pete]

If we assume the mounting horns are spaced properly to factory specs and not twisted or skewed, then the bumper will be under some slight stress when installed due to being bent.
These bumpers can be bent in the middle very easily, just by placing on 2 blocks and stepping on them. HOWEVER, that is not a good idea without some way to know how much pressure to apply.
A highly scientific way to do this is, place the bumper on 2 padded 2 x 4's on the floor. Place a pad on the center of the bumper with a bathroom scale on the pad. Measure the height of the bumper from the floor in the middle. Record that number. Step on the scale with ONE foot and press to some value you think will move the bumper slightly. Take a new measurement. Repeat process till you get the bend you want. If you over bend, turn the bumper over and go at it again.
Using the scale the bending force is somewhat repeatable without going too far.

 

[wrndln]

Thanks to all that responded. I like Pete's method. I was thinking of using a bottle jack under a solid opening above to force the bow downward, verses stepping on the bumper bar. That way I could control the "bend" a little easier - a little at first and then more until it is straight. I will report back the results.
Rusty Nelson