Warping and unwarping a trailer

[rmball28]

A couple of weeks ago my dexter torsion axle arrived and it was time to put wheels on my home welded frame (2x2 14 ga). I had ordered weld on side brackets and so I, well, welded them to the frame. I bolted the axle to the brackets, mounted the tires, and then flipped the trailer upright so that I could bask in the glory of my new home made trailer. After strutting around the back yard a bit and informing our dog of my trailer building prowess I noticed that the right left corner of the trailer seemed to be drooping. Surely it had to be an optical illusion since when i welded the frame I measured here there and everywhere with a level and strings stretched from corner to corner. Unfortunately when I pulled out the 6 foot level and laid it along the side rail the rail now had a bend in it that resulted in an inch and a half droop at the end of the trailer. The bend was clearly in the area of the welded on side bracket. I said bad things. The dog snickered. I had hurried while welding on the side brackets ( my daughter was helping me out between calls to her boyfriend and I knew the phone was due to ring soon) and the heat had warped the side rails. After a week of sulking and pouting I decided to try a technique I had read about in Welding fabrication and repair by Frank Marlow (recommended) called flame shrinking. It involves heating the outside of bent tubing to a dull red with an acetylene torch while keeping the other side and surrounding areas cool. Lo and behold after several gingerly applied heatings it worked! If you have a warped trailer it may be worth a try.

[PaulC]

Good tip The same can be done with an arc welder. You just have to be careful of not applying too much heat. Spread your strip welds along the area that has bent and keep an eye on it. Grind them off once you have it straight enough.
Cheers
Paul

[2bits]

Thanks for posting your horror story! It can (and will) be a help to others! (Like ME I am very glad you got it straightened out. Tack this up on the wall as Reason #116 not to distract daddy while he is working!

[cuyeda]

Just for the record, what type of welding was used for the initial installation?

[Dean in Eureka, CA]

'Nother way to do it is how a certain Norwegian went about it...
1. Clamp an I-beam with very fat or tall spacers at the high spot & any other non bent areas to the bent frame member.
2. Attach a "come-along" to the low spot on the bent member and the nice straight I-beam.
3. Tighten the chain on the "come-along" to where you actually have a reverse bend, then loosen... If you guessed right, the frame member will now be straight.
4. Repeat #3 if neccesary...

[rmball28]

The original welding was done with .035 flux core wire in a lincoln 175. Usually I use mig but it has been too windy to use mig outside.