feedback on flatbed design

Unless the OEM hitch is in your way, I'd leave it. That hitch is STOUT. 2nd gen's came with a class IV hitch, which is pretty ridiculous for a vehicle with such a low towing capacity. Overkill for sure.

 

Thats what I meant. I really like the hitch design in my rear tube bumpers so I am planning on just using that without the tubes. Hitch and recovery points frame mounted, everything else flatbed mounted.

This is an excellent point. I didnt even consider this due to it being low hanging fruit offroad

 

Have you considered any diagonal bracing or gusseting? Not sure how much you plan to wheel where you might smack the side of the bed, but a little bit of diagonal bracing/gusseting can strengthen a structure like this significantly without a whole lot of additional material.

Additionally, have you considered mounting points? Do you plan to use fasteners or weld straight to the frame? Make sure you have decent load paths for any forces you expect (from the structural weight itself, items you'll put on the bed, wheeling, etc.). You may want to shore up the frame in certain locations as well. Do you have access to any FEA tools (and someone proficient in FEA to do the analysis)? Would be good to validate the design against anticipated forces as well.

Another concern would be weight, as others have mentioned.

Overall, looks like you're headed in the right direction.

 

Does anyone have dimensions of this bed

 

you bring up a good point. this might not be what you mean, but I might try replacing the standard cross section of the upper frame with diagonal supports, and this might also help to reduce weight a little, especially if I try experimenting with C channel.

I have vertical 3x3 tubing that I plan to weld to the chassis, across around 4 points on each side. im not sure if this is be best method. I was also considering two long beams than connect directly to the chassis, but I'm not sure how good that will be, and it will be adding more weight.

I am also unsure about what you mean by this, thanks.

 

Years ago I worked briefly for a company that installed equipment on work trucks. Service body's, dump beds, built hydraulic for heavy equipment and such. We used large flat bottom U bolts to clamp the flatbed to the frame.

 

interesting. do you know how exactly they were mounted/how liberally they were used?

 

Not really. This was about twenty years ago, and I only worked there about 6 months. Iirc, the threads were down. So the saddle was on the c channel of the flatbed. These were mostly 1 tons and 1.5 ton trucks. Seems like there were 4 per side, but I can't remember for sure.

 

I dont see any reason not to use the oem mounting points...

I wouldnt do this with a tacoma. The frame is flimsy as it is. Cab and chassis trucks actually come with specific directions on how to mount stuff to the frame and how to load it.

 

Nice find.

 

Maybe I missed a reply on this. Long time flatbread owner user speaking.

What are you doing for a head board/headache rack? You’ll want something connected to the bed that keeps things from hitting the cab.

As you build/design keep in mind that having the option to put sides on the bed is really handy. Stake pockets or hinged mini sides are key. Makes going to the dump or picking up some soil a lot easier.

Lots of tie down points are key too. Personally I would think about rope hooks as well as places to secure straps. You’ll want to be able to tied to that head board from time to time as well.

Looks good so far. Go for it!

 

glad you sent this. I might not have thought about covering the fuel tank, yikes.

and do you know if I will need a new fuel filler neck? or could I re-orient the old one?

I saw this person do something like this, but im not sure what modifications they did to orient it like that:
https://www.tacomaworld.com/threads/flatbed-information-thread.558179/page-3

 

Oh, that wasnt the point of sending that... I just meant cab/chasis trucks are alot different then even 3500 duallies and even more different than a tacoma.

Filler neck will need some tinkering from what i have read. No details cause I havent done it yet.

 

Hello, tis been a while life has been busy, and I'm lazy :/.

I have tried to re-design the main structure and bumper, putting in thoughts of removing some weight and making bumper good, still iffy on the bumper.





I switched from using a big sheet of whatever, to using 2x6's resting on 2" c channel and bolted on. I also added the strut channel for more tie down opportunity. I will add D clips in the corners potentially and on the outer 3" c channel.


this is the main frame under the boards, the two central bars are 3x3 tubing, the outer are 3" channel, and the cross channel is 2".


I connected the bumper directly to the chassis this time, and will used 1/4" plate to connect it to the chassis. I added some some 1/4" plate to additionally hold the hitch and provide support, as well as to provide some shackle points. its currently pretty far under the bed considering I extended it a lot:

I've seen some long hitch extensions, but I don't know how much I trust that/how much they can take. I've experimented a little bit with using 3x3 to extend the bumper and hitch out more so that its right under the edge of the bed, but it looks sketchy:




I plan on adding a headache board and some side railing, still not sure about how i want to design that though. I will also add a license plate spot and some rear lights. I might still do the long middle drawer, and I do want to put some other storage under the sides.

here are some of my ideas: