MasterOfNone

I have a build thread started while waiting on my motor to get back from the machine shop. But wanted to make a new thread for the frame work I’m hoping to get done in the meantime.

The rust isn’t bad at all, but the very rear crossmember is very thin and has a few holes rusted through it.

Plan to buy a flux 125 welder from harbor freight soon and learn to weld. Any tips on how to fix up that rear crossmemeber a little bit? What type of metal to use? Do I cut out any or just weld a thin slab on top? I’m clueless. Would hope to avoid cutting it out and adding a round tube there as it’s still pretty solid. Just don’t want to do nothing and leave it as is.

Once the welding is done and the rear frame is cleaned up and degreased, I plan to paint it with POR-15 & their top coat(will be a while before it sees a bed $$$$)

I also have plans to build a flatbed flatbed once I know how to make a decent weld. Have done a ton of research on this but feel free to share your flatbed build and any tips.

I will include pics of my frame and pics of several flatbed builds that I’d like to sort of combine ideas from each and make my own custom one.
Id like to make a rack up top to put a canoe/Kyak or boards and still have the flatbed freed up.

MasterOfNone

Bought the welder and spent a few minutes practicing here and there. Am able to lay a decent bead but am still learning how different metal thicknesses weld and how to set the machine accordingly.
Have decided to scrap the flatbed idea, but will still consider it down the road or maybe on a 4x4 truck(plan to buy one some day).
For now, due to all the $ being spent on this truck, I’ll just treat the bed rust, weld patches where needed and paint the bed floor and underneath with por-15 with the top coat on areas where sun will be on.
Spent an hour today dregreasing, scrubbing and wirewheeling the back half of the frame.
Plan to do this several more times until I feel as much of the grime is off as possible. Not sure if there was some type of factory rubbery coating or if it was added aftermarket, but it took the wire wheel and drill to remove. Going to hit the bare metal spots with ospho to etch before painting if they haven’t rusted by then.
-(Should I paint the brake drum & backplate with a high temp paint? Do you think the POR-15 will melt off there?)-

Still sort of want to brace the weak points where rust has started.. (the round tube crossmemember & the rear thin crossmemeber that the spare tire mount is bolted to).
Thinking of inserting a 1 1/4” steel bar inside the round tube(after cleaning out the rust inside and sending some ospho through it) (May tilt the truck to one side, cap one end & fill the tube with ospho and let it soak for a day or two, then rinse).
The 1 1/4” bar could be welded at either end after being pushed through the existing tube. Figured it would add some strength in case the outer tube rusted through.
Not sure what to do to re-enforce the rear cross member. Any suggestions?
The engine build I’m doing should last me 10++ years and just want everything else to last that long as well.

So to thise whove done some frame reemforcement or have any ideas how to strengthen and add a longer life to mine, please chime in.
Thank you

MasterOfNone

I’ve scrapped the flatbed idea for now and am just going to try to strengthen the crossmemebers and touch up the bed rust until I get better at welding.

what would you do for the very rear crossmemeber if this was your truck?
Weld a similar thickness slab of metal across the whole top, cut to the shape of the topside of that crossmemeber?
Weld small patches for the missing material only?

And the round tube crossmemeber in front of it is still strong, but rusted inside and out. Was thinking of sliding a 1 1/4” pipe inside and welding at either end. Would you suggest this or setting else?
My goal is to beef things up so that the frame will last as long as the engine I’m rebuilding for it.

Thanks

raf

Hi @MasterOfNone I'm curious how this frame repair went for you. That circular cross member on my truck is almost completed eaten away so I'm looking at a similar project. Did you end up welding plates onto the existing structure or did you remove and replace?

MasterOfNone

i left mine in place, ordered a very thick walled steel tube, smeared it with wheel bearing grease and shoved it in the existing tube.
cleaned off the ends and welded it from either side, up and over the old pipe and onto the outer face of the frame.

But if mine were like yours and almost gone, I’d have cut the old out, ordered a pipe that fit the leftover hole, and if the frame was rotted where the old pipe went through, I’d add some thick plates, and drill a hole in them to accept the new pipe.


Mine wasn’t that bad, only had one or two very small holes in it which I welded up.
basically have a steel tube/grease/steel tube Sandwich now. Even if the original rots away, it’ll take forever to get to the new pipe. I’m no expert, this was the first welding job I ever did. Bought my first welder the day I took my bed off.

MasterOfNone

As far as that rear crossmember that holds the spare tire, I bought some plate steel from lowes, traced and cut 3 pieces that made up the width, hammered the edges to follow the rounded edge and welded.
Etched the whole rear frame with phosphoric acid, washed off while it was still wet.. and painted with POR-15

raf

Thanks for the update. I like this idea. I'll know more once I get the bed off, but I think my frame in the area where this cylindrical cross member attaches is in good shape, so I may do this tube-in-a-tube approach. I can probably find a new pipe whose OD is close to the ID of the rotted pipe and fill any remaining gap with a shim.

Thanks again for the suggestion, it's very helpful.

MasterOfNone

no problem, I forget what website I ordered mine off of, but it shipped right to the house fairly inexpensive. I went wayyyy thicker walled than needed but know it’ll outlive the truck haha
good luck man. Post pics in here if ya do it.