The Stovebolt Site Forums The Shop Area General Truck Talk Welding Frame Reinforcement Plates

After cutting my longbed frame to shortbed specs, I am now welding in reinforcement plates on the inside of the frame for extra strength.

A friend of mine says I should not weld along the vertical edges of the patch, just the horizontal edges. He says welding across a beam will weaken it.

Any thoughts on this "theory"?

Thanks!

Larry

I'm no metallurgist, I have heard/read the same theory,,usually folks use a diamond or "Z" shaped reinforcing plate(fish plate) for this reason,,the welds are then at an angle to the beam. brian

I think if you let everything cool naturally after you weld it, you'll be fine. Just be sure you are getting the proper penetration and don't weld in long intervals.
Scott

Used to work for a fellow that was a well known chassis builder and very safety concious. Here are a couple frame splicing tips I picked up: frames are designed to flex so never box a short section of "C" channel frame, this will make that section rigid and set up stress points that will crack at each end of the boxing plate. Next, don't use plate that is grossly thicker than the frame itself--same reason. The diamond shape reinforcing plate is preferred with a hole halfway between the point of the diamond and the part thats over the splice so it can be rosette welded. This prevents humping or twisting in the area between the perimeter welds. Taper edges of the frame joint so you can get 100% penetration without excessive heat from your weld. Now I just wish I had paid closer attention to anti-dive and Ackerman angle from a master but a teenage kid has other things on his mind, especially if it's in tight jeans.

Coilover,
those are some excellent tips. The first point seems to be something poorly understood by many people, judging by the articles I see in magazines.

Hopefully when you cut/chopped the frame you made a Z cut or offset cut and not a simple one.
It's much stronger than a verticle or diagonal cut. Then if you'd like weld a second plate over the z cut.