Bodywork

[RickL]

Well I tried to fix some of the cab sheet metal on the top of the cowl on the cab of my M37 and made a complete mess of it. Any suggestions on what to do?

Its really ugly and I prefer not to show pictures.

Rick

[powerwagontim]

Lots of Bondo will fix anything!! Without more info, thats about all I can come up with.
Tim

[JimmieD]

Proper application of a body hammer and dolly can do wonders. If you see that you need to stretch the low metal, and shrink the high metal, you're on the right track. Therefore in many applications you might apply dolly and hammer work to the low spot, to lift it up, and bring down a high spot! Seems backwards, but that's the way it's done.

There are some drill attachments that are used to apply heat to the metal by abrasion. The metal is first heated by the disc attachment, and then when it cools it shrinks of itself. This can be repeated several times, but of course one must be careful to not remove metal in the process.

You can also use a torch, with heat applied judiciously and carefully. I'd check Eastwood's Restoration page for that attachment.
JimmieD

[MoparNorm]

Jim's correct,....

...there are some guys who do perfect body repair with only a metal, non-abrasive wheel to heat and shrink. But with simple body tools, as Jim mentioned, practice on a less visible protion of the truck or better yet on an old fender that you aren't using. Then go back and work on the cowl. Bondo is not the answer for really flexible areas, it is only for smoothing out the final product in very thin layers. Otherwise your "repair" is liable to pop-off the first time your truck flexes off-road. There is a bondo type product that is actually metal filler with a two part catylist that is much better than body putty.
MN

[powerwagontim]

I was just kidding about the bondo. I bought a really sharp Mazda pickup in the 80s. The week after I got it the whole rocker panel fell off. There must have been 2 gallons of bondo, shoved into the holes. They used shop towels wadded up to keep the bondo from slopping out the back. Not very impressive and it showed me the evils of excessive dondo. Norm is right (that's the second time tonite) bondo is best in a very thin skim.
Tim

[tonkadoctor]

Bondo is Great when used properly

The correct way to do bodywork is to get the metal right first.

If you are repairing a rust hole you need to cut the metal back to good clean solid metal (you won't be able to weld to thin rusty metal).

Shape the patch as best as you can until it matches the contours of the hole NOTE: you want the patch to be larger than the hole, leave about 1/4" excess.

Now slightly recess the metal around the hole with a SMALL hammer so the patch will be flush with the surface of the body.

Now grind all the paint and surface rust away in the area and also on the patch ( if your using rusty metal to patch with shame on you).

TACK weld the new patch into place. DO NOT try to weld a solid bead on the sheet metal unless you are using a TIG welder. Try to use a MIG welder with solid core wire and argon gas, not flux cor wire if possible(110v MIG welders from sears or century work well on sheet metal) or braze the patch on as SMAW(commonly called STICK) welding is worthless for welding thin sheet metal (you'll blow alot of holes in your work or get really frustrated with stuck welding rods)

Now grind down the welds and rough up the surface of the patch and about 3 to 4 inches around the patch down to bare metal ( Fiberglass and Plastic Body fillers will not stick to paint for very long).

Now check that there are no high surfaces on the patched hole.that will protrude from the filler when complete if there are just "adjust' them with a small hammer.

NOW Time for Fillers.
_______Use a fiberglass product for the first layer (BONDO is NOT waterproof and will bubble in less than 6 months due to moisture trapped behind it, FIBERGLASS IS), I preffer to use Tiger Hair or a similar prodict as it has the fiberglass strand already mixed into the putty like resin. Spead a thin SMOOTH layer and allow it to set then rough it up with a grinder or high speed sander and make sure that it is at least flush with or slightly below the finished surface you are repairing (you don't want high spots as it is much harder to sand than the plastic fillers and will result in low spots.
________Now it's time for the "Bondo", spread as smooth a layer as you can (once it starts to harden stop working it or you will have a hard to sand mess). once it is hard you can sand it to shape. repeat as necessary.

One trick I use to "feel" if it smooth is to close my eyes and feel for imperfections.

Now admire your work. and spray some undercoating on the backside of the patch to seal it from moisture

If you are just pulling a dent don't drill a half million holes for a slide hammer like the amature books tell you to. If you have a cheap slide hammer that is used with a screw in it remove the screw and install a hook. now you can tack weld (more tack than weld here please, it's OK if they break off you can tack them back on) 3/8" washers on the dent and use the hook to pull on them like a professional shop will do. The shop I used to work at actually had a spot welder that was made for this purpose. When you have the dent pulled to where you want it simply break off the washers and grind the welds smooth (that's why I said more tack than weld)

For filling a dent (that you didn't drill a half million holes in) get the metal as smooth as you can first and you can simply spread a thin smooth layer of bondo and work it to perfection

Now if you drilled all those holes, buy a new panel and weld or bolt it on as required as it will become a cancer project. or you will be really good at welding holes in sheetmetal.

Good Luck

[CGarbee]

Mind if I add this post to my paint/bodywork page??? It is a better description than what I wrote a few years back...

[tonkadoctor]

It would be an honor CGarbee

Mr Garbee, You have my permission to place any articles that I write on your fine website.

I do this like many others to share and teach what I have learned over the last 25 years of metal and body work and turning wrenches........."Give a man a fish and feed him for a day, Teach a man how to fish and feed him for life".

I should meet up with you at the Golden Corral in Cary on Saturday and meet some of the other members of the NCMVPA for the Christmas parade (been a member for about six months but time hasn't been on my side for the meetings). Got any room for a passenger as my M37B1 is torn down to the frame right now.

[JimmieD]

Hey Doc,

I was going to make a comment in reply to your post, but I believe Mr. Garbee has said it all, in few words!
JimmieD

[CGarbee]

Doc,
Will be honored to have you ride in the '53M37 with the Cummins. Really looking forward to meeting you in person.

We need to get a few events going in the eastern part of the state, shorter travel for you, and a good excuse for me to get out of town...

Thanks,

[tonkadoctor]

Time is my problem not travel

Thanks CGarbee and JimmyD for the kind words, the Raleigh area isn't too far for me it's that stuff happens and always on the wrong day to be able to meet you guys and participate in the events.

It would be an honor to ride with you.

on the NCMVPA site I posted that I would show up and let ya'll figure out what to do with me unless someone needs me to go to their place to drive another vehicle that they want in the parade for them.

Really looking forward to saturday, should be a great time with a great group of people.

[RickL]

shield your eyes

Sorry for the delay I had to get some batteries for the camera, This is not pretty but here is the damage

[RickL]

more photos

This is the attempt at a repair on the opposite side.

[RickL]

more

more photos

[RickL]

more detail photos

This appears to have warped due to the heat