Repairing single wall truck bed?

[MushCreek]

I have an early 8' Ford step-side (flareside) bed in need of repair. The 8 footers are rare, and I got it cheap, but it does need work. I need to weld in some patches, but how do you do it when both sides are visible? The only thing I can think of is to make the outside look good, and put bed liner on the inside to disguise my work. This is going to be a farm truck, and doesn't need to be show quality, but I'd like to do a lasting and passable repair job. The worst part is at the bottom where it attaches to the floor. I figured I could cut the bottom inch off cleanly, and make up a bent piece and weld it on. Kind of like angle iron, only the same thickness as the bed walls. I'm wondering how to make it look at least OK.

Years ago, I custom made a 6-1/2' bed, but the bed walls are flat. The 8' bed is several inches wider, with an inner wheel well, so making a bed is out of the question for a shade tree hack.

 

[NYBODYMAN]

If you know how to weld and metal finish properly, the repair wont be visible. Takes a lot of practice.

 

[gearhead1]

Weld and grind, then sand the joint. You’ll never tell it was done unless you distort the metal. Use a Mig and spot, then go back and spot more. Then go on the other side and do the same thing. If it’s thick enough you cam almost weld continuous but if it’s thin, spot welding will work. Otherwise the sheet metal will be wavy.

Now on the bottom angle, put a step in one of the pieces so the outer surfaces line up.

I use ones of these in a air chisel (air hammer):
https://www.eastwood.com/pneumatic-...MIp7bliabB5AIVCRgMCh1gTwqTEAQYBSABEgIp2_D_BwE

HF has something similar, but dedicated tool:
https://www.harborfreight.com/air-p...MIp7bliabB5AIVCRgMCh1gTwqTEAQYAiABEgLb2fD_BwE

 

[MushCreek]

The metal is pretty thick compared to a regular car body. Will that tool handle thicker metal? And of course, there will still be a step on the inside. I guess if it's consistent, it won't be noticeable.

 

[gearhead1]

I’m guessing 18gage or thinner. 18 gage is about .050” thick. Do you have calipers or something to measure thickness?

 

[bad_idea]

**** weld the repair in. Fit the steel up with a consistent .040" gap all the way around the patch panel. Tack the panel in every few inches, then tack onto the tacks, then sand welds down with a Roloc disk. Set your mig right and you will get a good weld that has the same size bead on each side of the panel - only need to weld from one side.

 

[e015475]

"MP&C" is a frequent poster on the GJ and I've learned a lot from his write-ups on metal patching.

Suggest you look up his thread on this forum for additional tips on welding in patch panels. It is excellent.

M&PC uses a MIG welder with EZGrind wire and gets excellent results. The method I've used is a line-on-line **** fit welded with gas or TIG, but they're several ways to skin the cat.

Whatever welding method you use, it is going shrink the panel in the heat affected zone pretty severely. The only way to 'make' more metal to compensate for the shrink is to hit weld with a body hammer using a body dolly as backup. This will flatten the weld and stretch the metal.

Ideally the 'shrink' from welding is compensated by the 'stretch' from hammer and dolly work, but my experience from flat panels is that I chase the shrink too much and the panel starts to 'oil can', then I have to spot shrink with a torch to get some semblance to flat.

Flat panels are much more challenging than crowned panels to get straight after patching and you'll need a fair amount of hammer and dolly work on the weld joint. MIG weld beads are usually quite hard compared to those from gas or TIG, so gas welding might leave it a little more workable.

My experience with patching old single wall truck beds was that it was easier and more economical to buy a new on from MarK in Oklahoma than pour a bunch of labor into an original. You might give them a call and see if they make bed sides for your truck.

 

[MushCreek]

The 8' bed sides are not available. The problem is that they have an integral inner fender because the bed is about 3" wider than a short bed. I have no idea why Ford did this (I have no idea why they did a LOT of things), but I doubt anyone will ever duplicate those bed sides. I have fabricated a short bed before; I could simply make an 8' bed in the same width as the short bed. The 8' bed is an oddball; you can't get the wider crossmembers for it, either. You can get repop bed fronts and tailgates, though.

One of the rarest bits is the steps that go in front of the fenders. No one seems to reproduce those; not even in fiberglass. I've thought about making a mold and seeing if there's any market for 'glass ones. I have a good set of short ones as well as the long ones.

I measured the metal, and it seems to be about .057 thick, but I have no idea how much of that is paint. The sides are quite heavy, though.

I'm going to call around and see if I can find a sheet metal shop that could bend up some sides for me. The way I made the last one, I had the top flange bent, then welded a piece of tubing to create the roll. If I can get the sides made, all of the other parts are available for the narrower bed. Or I could add wheel tubs if I wanted to go with the wider width.

 

[metlmunchr]

Allowing for paint and primer on both sides, the sheet metal is probably 18 gauge (.050" thick).

I agree with the idea of getting new bed sides formed. By far the most difficult places to patch are dead flat surfaces. The more curvature, the easier it becomes to get a good job on a rust patch.

The bends can be formed either with a sufficiently heavy manual leaf brake (10 ft X 16 ga is a common manual brake in sheet metal shops) or in a press brake. I'd look for a shop with the capability to shear the 8 ft sheet lengthwise as opposed to one that would use a cnc plasma cutter to cut the sheet. Air plasma leaves a nitrided edge on the cut that needs to be ground off prior to welding. Thicker material is not a problem, but on thin stuff the edge makes for problems when welding.

Also, if there are any beads formed in the original parts, it would probably be good to duplicate those in the new parts using a bead roller as such features make a big difference in the stiffness of an otherwise flat sheet.

 

[MP&C]

How wide is the integral inner fender (offset from bed side)? You could make the bed side, cut out the inner fender opening and use a tank roll die to form half the radius inward, then form the inner fender and use a tank roll outward and **** weld the two together in the middle. What part of SC? I may know a guy..

 

[MP&C]

Example of tank roll dies...

By using same dies on your piece but going opposite directions with the radius it would provide your offset.. They also make tank roll dies for bead rollers.

 

[chilow]

That's clean!

 

[MushCreek]

I haven't measured the offset- maybe a couple inches? As I said, I could just buy wheel tubs and cut them down to the right size, or I could simply make the bed the narrower width of the short bed. I'm not sure why Ford made the long bed 3" wider.