Trailer build/restore order of operations

[Ryan_S]

What is the best order to start repairing/rebuilding an old M416 trailer? Is it best to get it sandblasted and cleaned up first, then tackle the patching/welding? I'm thinking sandblasting will give me a better idea of what I have to work with, but do I need to get it primed right after? Then I would need to touch up everywhere I patch.

It has quite a bit of rust perforation along the top of the tub, so I'll need to patch that. Someone cut the tailgate, so I need to work on that to get it how I want.

I'm new to welding as well, so there is going to be quite a learning curve here.

Thanks for any help.

 

[Titanpat57]

and the trailer bug bites another unwary victim...:ylsmoke:

Depends what the plans are for the trailer itself. What you describe now is a great start though. I was relatively new to welding when I started, but with the help of some members got on the right path.

 

[greentruck]

The M416 bed is bolted to the frame, so to get a good clean slate, taking the bed off would be the first step, allowing you to get at all the rust effectively.

I would then get it sandblasted. Our M101 CDN was in pretty clean condition, but its bed is welded to the frame, so they did as good a job as possible. There was some rust showing in the front floor of the bed, from the puddling of water sitting out in the elements. It was mostly surface rust elsewhere.

The sandblasting took things down to clean, solid metal, which revealed a series of small pinholes in the floor where the water had puddled and rusted it at the front of it. I'm not a welder, so I used body caulking and riveted a reinforcement underneath to seal and strengthen it there, closing and sealing the pinholes.

Thus, if you do want to repair all the bad spots, you need to sandblast first to remove all the rust damage and show where all the repairs need to be done. It's also possible to do just a light sandblasting mostly to remove loose paint and rust, but then you'll overlook getting it in as good as shape as possible before you proceed.

 

[TacoDell]

When I started my M100 project...

I used a flap disc and the cup brush (nylon) to clean up the metal surrounding the holes and corroded areas.
Once cleaned of rust, I re-welded (filled) what was necessary...
Then shot that with primer to keep it clean.

If you are going to need to fill any holes in the sheet metal of the tub...
I recommend purchasing a copper or aluminum backing plate or spoon...
Many places, including harbor freight, carry an copper spoon for cheap.
It works... but doesn't dissipate heat as well as something that is thicker.
Copper spoons are usually about an 1/8" - 3/16" thick.

Something better would either be... a copper or aluminum buss bar or a spoon of greater thickness... ie: 1/4" - 1/2".
The thicker the better, as that will make it easier and faster, for your weld fills.

If it were me... I'd do a blasting after I had the major work done...


because, it will need to get a primer coat immediately after the blasting, or it might start to show signs of rust. ~dependent on the humidity percentage of your location~
Here in SoCal (southwest) I can get away with bare metal for quite some time... as long as it doesn't get wet.

If it were my project.. I would work on the specific areas in need of repair...
when that area is completed... rattle can some primer on there and move on to the next priority...

Whence you get the worse damages repaired...
Then have it blasted and primed...

and then come back and do the final touch up work... re-prime those areas that were worked again...

and when you feel satisfied... bring on the paint. :2cents: