Bed Support "Cross Sill" Options

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etc86

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If you're not looking for a 100 point trophy, what about box/rectangular tubing? I will neither confirm or deny I've used PT 2x4's.
Happy to use toothpicks and spit if it gets the job done. I’m just trying to get as close as I can so I don’t have to spend days trying to get the body lines right. Or extra days.
 

DanMcG

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So the one’s between the wheel arches, are they around 1.5?
I measured 7/8" on the short ones, I'll check again when it's a little lighter out. And they don't ride on the frame rails but maybe 3/16" above it
 

etc86

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I measured 7/8" on the short ones, I'll check again when it's a little lighter out. And they don't ride on the frame rails but maybe 3/16" above it
Ah ok. So they’re basically just a structural support to stop the middle from bowing in or twisting. I really appreciate the help with this Dan, and I’m sure the next person that runs into this will as well.
 

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Seems like the best bet is spend the $15 for a new set of bed bolts, so you can just cut the old ones off and flip the bed over and tack the appropriate size tubing or some other steel shape to the bed.
I can’t imagine how you’d one piece anything up in there. Presuming you’re planning on doing more than just some redneck engineering. In which case if you’re doing that shove some treated lumber blocks cut to height in the offending spots and screw the truck bed to them so they don’t fall out.
 

etc86

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Seems like the best bet is spend the $15 for a new set of bed bolts, so you can just cut the old ones off and flip the bed over and tack the appropriate size tubing or some other steel shape to the bed.
I can’t imagine how you’d one piece anything up in there. Presuming you’re planning on doing more than just some redneck engineering. In which case if you’re doing that shove some treated lumber blocks cut to height in the offending spots and screw the truck bed to them so they don’t fall out.

The current set up is a flat tray and that’s basically square tube, rectangle hollow and steel plate but I’m going back to a stock style fleetside bed. I’ve got the front, side panels and tailgate and I’ll make a hardwood wood floor to fit. Definitely going to do it properly though which is why I need cross sill measurements. It’s the easiest way to get the bed lines to match the body. Everything else I can adjust by shimming or spacing but the less times the tub needs to be on and off the chassis the better. I generally over engineer but if it’s strong enough, lasts and works then I’ll go way outside the box.
 

etc86

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I’ll reiterate that I’m in Australia and freight on the rest of the panels was already pretty excessive but the freight on a floor by itself was quoted at 5k. For that money I can basically finish everything I want to do to it and then buy enough beer to celebrate with everyone that’s contributed. Also, another downside of being in Australia is that while there were a few of these made here there were a bunch that got made into flat trays for practicality and heaps of the tubs sat in paddocks or just rusted away. Then the boom in restoring these happened so any good condition beds were snapped up pretty quick so anything left is high priced and needs a bunch of work anyways.
 

Grit dog

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Wow didn’t pick up on the Australia part. I was about to suggest that you find an actual OE steel bed floor.
The front and back are just shy of 3” 2-15/16 looked like. Middle is just over 1” about 1-1/16”
Pictures are at an angle a little.
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DanMcG

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Middle is just over 1” about 1-1/16”
I'll have to recheck the short ones on mine, I'd swear they were just under an inch.
 

Grit dog

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I'll have to recheck the short ones on mine, I'd swear they were just under an inch.
Could be. I didn’t mic it. I measure or with a tape in the dark and cellphone flashlight. And everything has paint and original undercoating under it.
1” and 3” would be as close as anything else lines up on a squarebody, lol.

But I think the OP should mock up the bed on blocks, especially since he’s doing an uncommon modification. Idk if the number is totally applicable to what he’s doing anyway.
 

etc86

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But I think the OP should mock up the bed on blocks, especially since he’s doing an uncommon modification. Idk if the number is totally applicable to what he’s doing anyway.

That’s exactly what I’m doing Grit. I managed to find a scale pic and the measurements that came through from Dan matched so they’ll do. Sills are getting bent up anyways so it will have to. Basically I’m going to build it off the truck, get it all to the point where it can bolt straight on and then if anything needs fixing I can just shim here and there as needed. The sill height still matters because they’ll sit at the same height on the fenders as ones built into the body. Everything sits on top of those so if they’re close then theoretically the rest should be. If that all doesn’t work though I’ll set it on fire and pretend I never bought it.
 

etc86

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Built into the bed floor I meant.
 

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