For those who may remember, I've been working on building a large open car trailer. I had warped/bowed the frame from poor advice about welding the diamond plate decking on. The original bow measured 1 3/16" in the middle over a length of about 17'.
I used an oxy/acetylene torch to heat the bottom of each main rail similar to how the weld on the top was done in an effort to duplicate the heat input/warpage from the welding. I divided the rail into 6" long sections and heated 6", then skipped 6" and so on. I let that completely cool and measured for any improvement in the bow. I then went and filled in heating the areas left from the first heat session.
When I finished, the bow was reduced from the initial 1 3/16" down to about 1/8". It's not perfect, but I can certainly live with the final outcome.
Many thanks to those who gave me input and encouragement on fixing this warpage. It's nice to know that you fellas are here to help out when such situations arise.
Again...thanks.
Todd G
http://www.malibumotorsports.cjb.net.