Rust on body floor supports

[hatchetman]

I have several completely rotten floor supports behind the rear wheels, probably from years of use without mud flaps.

There are two types of underbody supports. There are "c" channel supports that are used to attach the body to the frame with bolts, these are all OK. The rusty and rotten supports are in between them. The "u" shaped ones I guess collected water or were just thinner to begin with. These "u" supports are just resting on the frame connected to the body.

I plan to strip the bus down to the sheet metal floor and put down metal paint after properly cleaning or repairing any rust on the floor as I've read on here already. Insulating with 1" of XPS followed by good OSB or plywood as a subfloor.

Should I be concerned about the floor supports that have rusted through? If so what remediation do you guys suggest. Without taking the body off the frame or cutting away the skirting I'm not sure how I'd get a full piece across from one side of the bus to the other to support the floor they way it used to be.

My inclination is to do nothing. I think my flooring plans will adequately spread the load safely among the "c" supports and the remaining "u" supports. Alternatively I could get the longest 2x4 I could fit to take the place of the rusted metal supports but it wouldn't be a continuous piece.

Thoughts?

[Robin97396]

That's the perfect project for good old American ingenuity. If you feel that floor support is going to be a problem at any time in the future it might be nice to weld in something to support it from any materials you've got on hand.

I'm with you. It's still supportive because of the sheet metal tension, so unless you want to put a safe or a piano back there it should be ok for now. It's good for a couple years. It might be a good place to put one of those sunken shower pans.

[tlbeck1985]

Mine are the same way. I'm going to pressure wash them, spray on a rust inhibitor and then truck bed liner from a can. That should definitely prevent a lot of the rust from getting worse. If I start getting soft spots down the road, I'll weld in some supports or something. I'm just not trying to dump thousands of dollars into restoring an old bus. I'm going to create what I want for my needs.

[Robin97396]

Exactly, fix it with whatever you have instead of spending money. I've been saving some bed frames for just such an occasion.

[Tango]

If they are old cast iron bed frames they are ca-ca metal. Use some real steel, it's not that expensive to do it right.

[Robin97396]

I don't know what those bed frames are made out of but my drill bits wont cut into them. It's just some 1" angle from old bed frames that doesn't have plans yet. There's got to be a use for it somewhere.

[hatchetman]

Thanks for all the great responses, I think I'll just keep an eye on it for now. If after ripping out the seats the floor is in bad shape perhaps I'll consider a repair before building out the rest of the bus.

[Rameses]

Originally Posted by Robin97396

I don't know what those bed frames are made out of but my drill bits wont cut into them. It's just some 1" angle from old bed frames that doesn't have plans yet. There's got to be a use for it somewhere.

Yes! I can't even begin to count the number of brackets and mounting tabs and whatnot that I've made out of old bed frames over the years. People throw those things away all the time. Anytime I see one, I pick it up and add it to the pile at our shop. It's much thinner than more common angle iron, making it easier to work with, and resulting in a finished product that weighs less and was made from free material. Win-win.

I don't think I've ever seen a cast bed frame. Got any pictures of one?

[Robin97396]

I'm not a metal worker, but my understanding is these bed frames were made of some type of quite hard steel. I always thought iron was to brittle to be formed into thin strips.

I do like that smaller size angle for indoor projects. I even cut up old TV trays for projects, and I don't even know what they're made of. I like scrap.

[Tango]

Newer steel frames are probably OK. As I noted, the old ones are usually cast iron, really low quality metal and prone to crystallizing. Not something you want to either try and weld or to ever carry much of a load.

[Robin97396]

For anything structural I would spend for some real steel. For my various little home projects I'll use just about anything that works.