C3 #3 body mount access cover marks

[Daniel T.]

Can anyone tell me why factory installed #3 body mount access doors have a black diagonal mark running from one corner screw diagonally across from top to bottom. I'm wondering if this was an inspection mark or over spray of some type. Seems to be pretty consistent on originals.🤔

[Don L.]

Are those lines on the inside or the outside? I suppose my eyes aren’t good enough to tell from the posted photos.

[Daniel T.]

Hey Don, they are on the outside.
I see similar marks on original covers that are listed for sale onsale. Also can be seen on page 243 Fig Ch9.2 of the 69 judging manual but nothing is said about it in print. 🙂

[Mark F.]

It seems odd to me, but it could be a registration mark for a check after the part was made at whatever stamping plant made those parts.

I say "odd to me" because the stamping plants I have been in have locating "pins"; or 1st multi-stage press clamping jaws for such a small part.

Could just be an oddity of the vendor who made these for GM ?

[Mike M.]

I've removed access panels from about 15 C-2 vets and never encountered suck marks. perhaps just a c-3 phenomena? mike

[Joe L.]

I've removed access panels from about 15 C-2 vets and never encountered suck marks. perhaps just a c-3 phenomena? mike

Mike-----


Not on my original owner 1969. There are no such marks on my access panels.

[Joseph S.]

I've removed hundreds of those covers in the last 40 years and have never seen those marks.

[Patrick H.]

Look at the plates, and think of both as being upside down as shown.

I think that the plate was hung from one of the holes, and in the examples it's the lower left hole. The paint dripped down from the hole in a diagonal, and thus the paint is a bit thicker there. Note that the stripe is narrowest and thickest at the lower left hole and becomes wider as it goes down.

I don't think it is a mark, but rather a paint drip.

[Daniel T.]

Thanks Patrick, that makes alit of sense. It's difficult to discern these marks from original paint because it is the original paint. Also these were dip painted. So, hung by one corner and dunked. This left a heavier streak of paint diagonally across the plate. As the paint wore away only the heavier area of paint remains leaving the streak.

[Mark F.]

...Also these were dip painted...

How do you know this ?

in my experience, very small parts like this were rarely dip painted...too much goop, drippage and troublesome handling afterwards...but I'm all ears for what documentation you have.

Also, with the two previous comments on C2s (never seen diagonals as in yours), when did they start dipping them ?

All of that information if you truly have it would be good for your TIMJG Team

[Patrick H.]

You can make runs like this spray painting them too, but easier to reproduce if dip painting.

[Daniel T.]

Oh believe me, I can make runs with a spray can 😆. I'll dip em. This makes the most sense. Paint would be on the wire hook and run down as the paint dries. Leaving a heavier streak across the panel.

[Patrick H.]

I've used Rustoleum semi gloss, and thin it down to the right consistency.
Inexpensive and works well.

[Joe L.]

Strange "factoid": these same covers were used on all Corvettes from 1963 through 1982. However, I cannot find that they were ever available in SERVICE.

[Daniel T.]

Hey Joe, probably just not much demand for replacement I guess. Available reproductions look pretty good.