Truck flatbed frame design?

[BMB]

Have a friends son who is restoring a 65 Ford F250 2wd and may want a flat bed for it.

I'm sure he would haul some stuff in it, but it wouldn't be a work truck.

I thinking of a frame of 2x2x3/16" angle with 2x2x3/16" angle cross supports and 2 "backbone" runners of 2x2x3/16" square tube.
The bed would be 2x6"s.

Thoughts on this design (see drawing)?

 

[TheEquineFencer]

It'd probably work until someone put something 1/2 way heavy on it and then it'll fold.

You use something like at least 3-4 inch channel for the main frame rails. It depends on if you plan to add a dump/lift later on. The last one I built I used 1x2 tubing for the cross sections welded to the 4 inch frame. I used 12 gauge sheet steel for the surface of the bed. It was an 8x12 dump bed for a F350 Ford. I laid the (3) 4x8 sheets of steel on the shop floor and got it all square, tacked the sheets at the seam so they wouldn't move and built it upside down until I got the bottom of the bed finished. After the sheets were tacked I tacked the 1x2 in place to the sheet steel then laid the frame rails on and tacked them. Once everything was tacked in place and looked right I went back and completed the welds. You move around doing the sheet steel welds so it doesn't warp and swell on you. At the sides of the bed where the 1x2 was I cut the 1x2 shorter than the sheet steel and welded a 1/4 inch x 4 inch plate to the side of the 1x2 so the plate tied the 1x2 and the 12 gauge together. I used 4 inch channel and tubing for the frame of the front headboard. I used a 4x8 sheet cut into (2) 2x8 section one to cover the front, the other to build a tailgate.

There's a lot of different ways to do what I did. I did this one as light and strong as I knew would work for what the truck was rated for. I've seen angle iron used for the cross ribs and channel too. It depends on what realistic loads will be applied to the bed plus a "fudge factor" IMO.

There's probably some regular chassis builders in here that can give more insight than I can.

 

[davidoff]

It'd probably work until someone put something 1/2 way heavy on it and then it'll fold.

You use something like at least 3-4 inch channel for the main frame rails. It depends on if you plan to add a dump/lift later on. The last one I built I used 1x2 tubing for the cross sections welded to the 4 inch frame. I used 12 gauge sheet steel for the surface of the bed. It was an 8x12 dump bed for a F350 Ford. I laid the (3) 4x8 sheets of steel on the shop floor and got it all square, tacked the sheets at the seam so they wouldn't move and built it upside down until I got the bottom of the bed finished. After the sheets were tacked I tacked the 1x2 in place to the sheet steel then laid the frame rails on and tacked them. Once everything was tacked in place and looked right I went back and completed the welds. You move around doing the sheet steel welds so it doesn't warp and swell on you. At the sides of the bed where the 1x2 was I cut the 1x2 shorter than the sheet steel and welded a 1/4 inch x 4 inch plate to the side of the 1x2 so the plate tied the 1x2 and the 12 gauge together. I used 4 inch channel and tubing for the frame of the front headboard. I used a 4x8 sheet cut into (2) 2x8 section one to cover the front, the other to build a tailgate.

There's a lot of different ways to do what I did. I did this one as light and strong as I knew would work for what the truck was rated for. I've seen angle iron used for the cross ribs and channel too. It depends on what realistic loads will be applied to the bed plus a "fudge factor" IMO.

There's probably some regular chassis builders in here that can give more insight than I can.

This is good idea!

 

[TheEquineFencer]

This is good idea!

Thanks, even a blind squirrel gets a nut once in a while.

A buddy I grew up with built truck bodies and beds. I get/got a lot of my ideas from him and his dad. His father has done this type of work for over 50 years now.

The main thing I learned from them is understanding how loads are applied to a bed or anything for that matter, then ways to spread the load along the entire body so you can make it lighter.

 

[sberry]

On that truck 3 and 4 inch channel are needed as it needs to have that much elevation so the tires don't hit the bed before it hits the bump stops. The frame isn't straight and linear. You can measure some crossmembers on a factory box.

 

[brownbagg]

just find a flat bed in a parking lot and look under it

 

[sberry]

30 yrs ago on a 78 250

 

[countryroad82]

Something to think about is including stake pockets and maybe a low rise headache rack. The pockets for getting straps in or even for sides you could fashion up. The rack more to keep cargo from bashing the back of the cab when some ***** pulls out in front of you. But Fencer is right on with his suggestions.

 

[Spareparts]

3" or 4" channel legs facing out down both sides of the bed with a radius around the tires with flat bar welded their mainly for looks and strength, great for attaching ratchet straps or chains across the bed. When you said 2 X 6 for the floor, I assume wood, if so recess the wood so it is flush with the frame of the bed, looks much better. I used 1 X 6 deck boards on my flatbed, plenty strong and lighter and cheaper, if you go that route get them early and let them dry, they shrink causing gaps.

 

[BMB]

You use something like at least 3-4 inch channel for the main frame rails. It depends on if you plan to add a dump/lift later on.

I had thought some about channel instead of angle and will look into it more.
No dump bed and no steel decking, just 2x6" boards.

On that truck 3 and 4 inch channel are needed as it needs to have that much elevation so the tires don't hit the bed before it hits the bump stops. The frame isn't straight and linear.

Yeah, I had thought about that and would be including some type of mounting to give it more clearance.

Something to think about is including stake pockets and maybe a low rise headache rack. The pockets for getting straps in or even for sides you could fashion up. The rack more to keep cargo from bashing the back of the cab when some ***** pulls out in front of you

He does want stake pockets and some sort of rack.


Thanks for the responses. I've got a while before he decides on anything an another year before he can drive.