The Stovebolt Site Forums The Parking Lot Big Bolts Rust between chassis reinforcers on '46 6400

The sheet metal on my '46 2-ton is not in bad shape but I am concerned about rust deterioration between the channel of the chassis and the outer steel riveted to it.
I hate to restore this lovely beast and find the frame was weakened by rust. The pieces have some areas where there are 1/8"+ gaps that held dirt and water for many years. The top of the C channel frame is pitted but it is this area I cannot see that bugs me. My original plan was to dig out and vacuum and dry this steel and then force
POR 15 or anything you might suggest into the cavity and call it good. I would hate to restore this very promising BB and find I should have paid a lot more attention to some aspect like frame rust. Any thoughts or opinions welcome. Any "rule of thumb" on rust or corrosion? I could drill out the rivets and look better (boy does THAT sound like fun!) or I could
weld in stiffeners inside the C channel as a precaution. Whaddya' think?

I had the same thing with my 46 COE. I clean everything as good as I could,blast or wire wheel and then soaked it down with Jasco prep and primer. It has the consistensy of water so it gos any where water went. It turns rust so hard I had to use a chisel to break a hardend puddle of off my floor! I used a deck sprayer. It's very toxic so be carefull,read the label. Best to let it dry for days.I got it at Lowes in a quart bottle.I soaked the body ,frame everything with the stuff and my truck was very rusty!! Hope this helps

My 46 ton.5 bus has the same issues. I am having new sheet metal folded to replace nearly all of the body spacers. On mine they were really bad. The coach body was designed in such a way that rain was intended to run down from the windows and then drain through fairly large holes in those brackets. Not a very good concept. The replacements will be Galvalume encased in fiberglass that will go a ways up the outer skin and hopefully make it all last for another 65 years or so. The originals had no paint or primer and I'm amazed anything at all was left.

I actually think I would drill the rivets and pop the outer plate before I would weld in new pieces. If the metal is rusty anyway you will have a hard time welding to it and expecting it to be strong. It is also likely (although I'm not really sure) that the frame is heat treated and welding to it would cause it to be weaker than if you left the rust alone. You have to remember that welding is the cheapest way of joining two pieces together. So if they could have Chevy would have welded at the factory....I think! It's been a little while since I was under mine and really looked, but I believe the rivets are solid and grinding the head off and hammering them out with a punch doesn't seam that unthinkable!

I run a fabrication shop, so my perspective may be a little different, but if I went the the trouble to pull the outer plates off I would more than likely just remake them! Possibly have them galvanized!

Just my $.02 worth.

What I found with some of the frame rivets is that they were installed in holes that weren't aligned. The rivet filled the void but trying to hammer it out was a problem.

Maybe this is a dumb question, but do you plan on doing things where you need the reinforcement?

If it's just a stiffener, pop the rivets and get rid of the plates. Just a thought.

Jeff

Believe it or not...my Wayne bus body has no rivets. The entire body, inside & out, was assembled using 5/16, slot-head screws. Even more of a bit*h to remove than rivets. To clarify, I will be spot welding the skin only to the ribs...not the frame. And once I have removed the old skin from the upper rub rails down, the spacers will be a breeze to get to and replace.

Gentlemen,
Always good to hear from the unofficial "Board of Directors" when I have these issues. I have been given plenty of perspective to think about. I'll let you know.
I know I won't be using this truck at its original maximum capacity but I do think
if the boys at GM thought it ought to have side plate stiffeners who am I to over-rule them? Probably err on the side of taking one side off and looking at it close.
Thank you!

I dont think anyone at GM added the plates to the side of the frames. I believe they were always added as an afterthought or some such reason by shops or farmers with welders to stiffen the frame when folks planned on overloading their trucks.

Can anyone show any factory documentation for this?

Jeff

Just for clarification --- the brackets I am referring to on mine fit between the edge of the floor and attach to the outer body skin. In the pic below you can see what is left of the one that ran next to the right rear wheel. The others are in only slightly better shape and I plan on replacing them all with new sheet metal folded to match the old specs.

[img]http://farm7.static.flickr.com/6146/6018987684_802b47fe73.jpg[/img]

I think the reinforcers are from the factory, my 46 GMC COE 2t has them and I have seen the exact siffeners on other trucks same vintage. I would guess that if they were added aftermarket they would have been welded on, mine are riveted. Rusted Nuts, I looked at your pics and you don't have them. Is yours a 2t or 1.5t

Tango, school buses are a whole different animal.

Jason, my COE is a 1 1/2 ton. My '41 was a 1 1/2 ton w/plates.

I've disassembled several different models of 1 1/2 to 2 ton trucks with all different combinations of either rivets, bolts or welds or combinations of all three. Many of which were the same design of 1/2" steel with an angled cut at either end.

Plenty of others I've seen have had frames lengthened so you could hardly tell plus with added plates, some were so mangled it was hard to miss.

Going through the factory specs I haven't seen any documentation to show this was done at the factory. I was hoping someone else could lend their opinions or expertise here.

Jeff

OP here:
I have seen Chevy literature that shows these stiffeners attached (rivets, welded, or bolted - hard to say) more than once, so I think at least in some applications they were factory stock. The '46 I have was a dump truck for many years and then a farm truck. I've decided to do everything I can to pick and vacuum and force air clean between them and then force POR 15 into the cavity and cross my fingers.
As a wise guy once alluded to: Life is too short . . . . Thanks for all input Mark

Speaking of "adjustments to the frame" by coach builders...

...as near as I can tell, my 160" wheelbase chassis was very likely almost three feet longer when it left the Chevy plant and was bobbed by Wayne for this "Shorty" configuration. The rear ends of the frame rails have obviously been whittled down with a torch and the total frame length is about that much less than what the book shows.

Make it fit boys!

From what I've seen GM riveted the the flat plates on the side of the big bolt frames foor many years

Especially w/ mis-aligned rivet holes, after grinding the head or tail off, drill a .25" or .375" hole partway through the rivet so one has a good location for an appropriatley sized punch.