CMP Fender to body joins

[Bruce Parker (RIP)]

I'm looking for information on the correct material seated between CMP fenders and bodies. Specifically I need to know what was used on a 1944 HUW but am interested to know (as I suspect) if it evolved during wartime production.
My foggy recollection taking the fenders off my HUW was that there was a thin strip of impregnated fabric along the joint. I also think 11 and 12 cabs had a material folded in half such that it formed a visible round bead along the seam.

What is correct? Any help appreciated.

[Harry Moon]

I have the front ones that go between the front fenders and the front clip, I'll post pictures.

[David Dunlop]

Hi Bruce.

If it helps at all, my 44 15-cwt Chev WIRE-5 had driver side original fenders. The fender welt on the two pieces was an oilcloth type of fabric wrapped around a small cotton cord about 1/8-inch to 3/16-inch in diameter. Width about one inch.

The left side rear fender section had been damaged, removed and repaired at some point. It had a simple flat welt in it that was an impregnated cloth with no bead on the side at all.

The same beaded welt showed up in the WIRE-5 2K1 Box finishing the seam between the walls and ceiling plywood.

Back in the early 1980’s, Spae-Naur carried a variety of the oilcloth beaded fender welt: different widths and bead diameters.

My guess is fender welting usage may have varied over time through 11, 12 and 13 Pattern vehicles, but at any given point in time, across all weight classes, Chevrolet was probably using the same welt. Simple economy of production.

Hope this helps and doesn’t confuse.

David

[Ganmain Tony]

Bruce,

I do realise you asked what was the original material that went between the guards.

I believe MAC's have a reproduction of what we call P Channel.

I got some from the local rubber store in Wagga. But it is completely rubber and has no cord running through it. (The original bits I found when dismantling the F15 did have a rope/cord in them)

I can take a picture and post it here if it helps.

[Bruce Parker (RIP)]

Originally Posted by Ganmain Tony

Bruce,

I do realise you asked what was the original material that went between the guards.

I believe MAC's have a reproduction of what we call P Channel.

I got some from the local rubber store in Wagga. But it is completely rubber and has no cord running through it. (The original bits I found when dismantling the F15 did have a rope/cord in them)

I can take a picture and post it here if it helps.

That would be great. Original is nice, but finding something that looks the part and does the job works too.

[rob love]

I have always made the fender welting with canvas and rubber cord. A welting foot on the sewing machine lets you get the cord sewn in nice and tight. Then I spray the whole thing with asphalt undercoating from a can. I do the same with cotton webbing I use for fuel tank brackets. Without the asphalt, the webbing just soaks up the water and ensures, combines with any rubbing action of the area, rust.



You will want to make sure the fenders are painted with a tough and waterproof coating like POR-15. I have seen many otherwise perfect fenders with pinhole rust through and severe pitting where the antisqueek welting was. That said, done right, it will likely outlive you.

[Bruce Parker (RIP)]

Rob, thanks for the asphalt undercoating idea. I like it and was wondering what to impregnate all my roof fiber seals with.

[Phil Waterman]

Hi Bruce


My 1945 HUP had the fender welt as used on cars of the 30s basically oil cloth folded over a bead of jut rope. But it all so had about 2" wide fabric impregnated with with either tar or cosmoline.


I bough the fender welt over the year but I have also made in out of good grade oil cloth, folding it and sewing in hard cloths line rope. Both have stood up well, but then again my trucks now live indoors so rust has not been as much of a problem in the second half of their lives as the first.


Cheers Phil

[Bruce Parker (RIP)]

Originally Posted by Phil Waterman

Hi Bruce


My 1945 HUP had the fender welt as used on cars of the 30s basically oil cloth folded over a bead of jut rope. But it all so had about 2" wide fabric impregnated with with either tar or cosmoline.

Thanks Phil, but can you clarify your comment above? Did it have the bead and the 2" oil cloth or different fenders (or trucks) having the just the oil cloth or the bead? Or was it the bead folded over making a 2" width?

[Owen Evans]

Not fenders, but if it helps at all, here's some photos of the different types of material (or remains of) from an NOS front shell for the 11 cab. I guess the 'fabric' type would be used on the 13 cabs, when rubber became harder to obtain? Note the black residue (tar?) used to seal the fabric type to the metal.....note also that the fabric has a textured outer finish, similar to the 'grained' products listed here:

https://www.vintagecarparts.co.uk/se...ry=Wing+Piping

Owen.

[Bruce Parker (RIP)]

Thanks Owen, that is very helpful. It makes perfect sense the early CMPs used rubber similar to their pre-war cousins. Then with rubber shortages they improvised a fabric (burlap?) coated in tar. I confess to taking little notice all those years ago when I took my fenders off but today am seeing a coated loose weave burlap like material under all the roof fittings as a waterproof seal. Tar and cotton was available and cheap.

[Ganmain Tony]

Gday Gents,

This is turning into a interesting discussion.

I found a front mud guard (Fender) which still has some for the original material on it. Definitely a woven material not rubber.

In the last two photos' the new example is laid out for a comparison.

[Ganmain Tony]

Just for the record - some pictures.

The guard is not bolted to the truck so it is difficult to get the complete fitted appearance.

[Bruce Parker (RIP)]

I'm forming an opinion (though welcome to be rebutted) that early CMPs used a civilian rubber seal, flat with a round outer that was soon replaced with a similar product made of canvas impregnated with 'tar'. What is certain is that a flat example of the tar impregnated burlap/canvas was used as a roof gasket at least on CMP HUPs. Distant memory perhaps, but on my 1944 HUW I wonder if the fender bead was replace with the flat seal. I think I would have noticed a bead and recorded it when taking them off.

[Jordan Baker]

When I took my C15a apart the body joints all had flat woven seal. There was no bead nor did it ever appear to have had a bead. I found that Mac’s Antique Auto sold the same type of seal.

[Jacques Reed]

Good Day,

Here are two close up photos of some original fender welting from my 1943 F-15A.
As discussed it has the cord sewed into the webbing material which I believe was impregnated with and anti-rust agent, Cosmoline perhaps?

I obtained a vinyl repro in Australia from Old Auto Rubber Co. They list it as mudguard piping in their catalogue. It is similar to what is shown in Owens UK link. The layers of paint on the original make it look almost plastic, so once covered in paint the new material will look very similar. See attached

Cheers,