Fighting rust on hat channels

I am prepping my body to finally throw back on my m38a1. I realized everything will get painted and duralined, except the inside of the hat channels. Can i squirt oil in there or something to prevent them from rusting from the inside out? Any options?

 

I squirted as much Rustoleum heavy rust primer in mine as a I could. Not sure how much good it did, but made me feel better.

 

Ospho. http://www.ospho.com/ Might have to call around to your local hardwares stores to see who has it. Usually Ace or True Value. It's essentially phosphoric acid, and it changes rust from iron oxide to iron phosphate (or something like that). It kills rust by chemically converting it to something different. Turns rust black, and it can then be painted over.

It's water-thin, and can be sprayed, brushed, or you can put it in a squirt bottle if you want and hose everything down. I'm going to soak every nook, cranny and seam on my tub before I paint it, even after I have it media blasted. Especially the hat channels and tailgate seams. I'm planning on long, skinny round brushes and rag mops on coat hanger wires to swab around the insides of tough areas. You could probably put it in a pump-up garden sprayer if you wanted to and spray it into the hat channels.

 

weld through zinc rich primer

 

Amen to what Ron said! I neglected to mention I sprayed Ospho in mine first...just the way he suggested. Then the Rustoleum (brush/roll on). Sprayed Ospho in every nook and cranny underneath before painting.
We used Ospho years ago in plants on tanks where we couldn't sand blast because of process concerns. Then painted the tanks. Not quite as good as sand blasting but a close second.

 

Yeah, use the Ospho first on the bare metal or rusty areas you can't reach, before any primers, sealers or paint. You could even coat the whole tub with it if you wanted, treat all the bare metal before priming as a first line of defense against rust. Sure won't hurt.

After I'm done with my chassis and I can put it in storage, I'm planning on building a tub rotisserie just like TommyB's, so that will make the bodywork mucho easier. I'm even taking it to the sandblasters mounted on it. When I took my frame in there was a guy unloading a car body on a rotisserie, they just wheeled it right into the booth and they can blast every inch of it. Making his job easier will save me big bucks.

That thing is sooooo sweet!

 

I couldn't get ospho without ordering it, so being the impatient son-of-a-gun I am, I use a product called Extend. It applies the same and reacts to rust the same so I feel pretty good about it. Time will tell I guess. But I figure by the time this tub is rusted enough to need more help, it will be time for a new tub.

 

Is ospho equivelent to Eastwoods rust encapsulator? I have a bunch of rust encapsulator sitting around, but I have no problem buying ospho if its better.

 

Completely different stuff.

 

My hat channels are full of wood (am I alone?). Can you guys still get these products in with that in there and still have any coverage?

 

I've used Extend a lot I still do when I can find it. Pretty good stuff the other stuff out there seems to be also. I really like the stuff that Eastwood sells.

 

That is the factory setup, and IMHO a big part of the rust problem.. Replacement hat channel doesn't have the wood.
Keith

 

I thought that would be the case with my replacement floorboards. Nope, new hat channels (new floor) had wood also. I guess the only way to eliminate it is to replace the channels only.