Boxing your entire frame seems pointless now

[dyeager535]

Hate to come in on the backside of this thread, but I am currently working on my own k5 build and am currently trying to adress some of the same frame flex issues. I have an engineering background, and looking at the frame, I think a lot of the problem is poorly designed factory crossmembers, especially in the rear. Before I attempt to do the frame boxing job on mine, I am going to just weld in tubular crossmembers and see if that corrects some of the issue. I am trying to build a driver that will see some occasional offroad use, so I would want to avoid adding a roll cage if at all possible.

I'm interested in what you find. From what I got from looking at the underside, all I could come up with is changing one in front and one in rear to tubular vs. flat, maybe another one at the extreme rear, behind the fuel tank. The drop in the center of the frame ensures that the drivelines and exhaust interfere with pretty much any attempts to span the frame outside of where the factory did.

 

[JoshHefnerX]

I'm thinking boxing the frame would act like adding a shear panel to the structure.. If you have some method of cutting large holes with edge dimpling throughout the center of the plates you add, it could add some strength w/o huge weigh penalties. Similar to wing spars on an aircraft.

 

[K85 Octane]

The next street truck I build will have a “half cage” in it. Haven’t worked it out but I’d love to run a “cage” that stays lower than window/bed rail height. Even in the bed it only has to be over the frame, so almost right along the bed floor would still do wonders for rigidity.

 

[dyeager535]

I'm thinking boxing the frame would act like adding a shear panel to the structure.. If you have some method of cutting large holes with edge dimpling throughout the center of the plates you add, it could add some strength w/o huge weigh penalties. Similar to wing spars on an aircraft.

If I had access to the tooling to do that, I'd box then do both sides of the frame rail.

 

[kennyw]

The only down side to the dimple die holes in your boxing plate theory isn't strength or torsion related, you would gain 70-100% of the improvement from the flat, solid plate with 50% or less of the weight. What you would have issues with it crap getting trapped and accumulating in the frame causing corrosion.