C2 core support paint question clarification

[Hector G.]

Was the radiator core support painted semi-gloss black or flat black? According to the latest edition of 1966 TIM & Judging Guide (Guide), on page 162, the Guide indicates that the "core supports...[were] painted semi-gloss black." It goes on to note that "The assembly was in place prior to the factory body blackout paint process and therefore matching the inner fender skirt finish." (emphasis added) Seems pretty straight forward, however, on page 154, the Guide states that the "Under hood surfaces; including firewall, inner fender skirts...have a flat black finish from the blackout procedure." (emphasis added) This would suggest that the core support was painted flat black. Any help on this topic would be greatly appreciated.




Hector

[Michael H.]

Re: C2 core support paint question clarification

Hector,

All under hood and engine compartment fiberglass items were painted semi gloss black.

[William C.]

Re: C2 core support paint question clarification

Same process, at the same time, same painters, same gun. Should all match, with allowances for distance from the gun, metal vs fiberglass surfaces etc.

[Scott S.]

Re: C2 core support paint question clarification

Was the radiator core support painted semi-gloss black or flat black? According to the latest edition of 1966 TIM & Judging Guide (Guide), on page 162, the Guide indicates that the "core supports...[were] painted semi-gloss black." It goes on to note that "The assembly was in place prior to the factory body blackout paint process and therefore matching the inner fender skirt finish." (emphasis added) Seems pretty straight forward, however, on page 154, the Guide states that the "Under hood surfaces; including firewall, inner fender skirts...have a flat black finish from the blackout procedure." (emphasis added) This would suggest that the core support was painted flat black. Any help on this topic would be greatly appreciated.




Hector

Hector, Michael and Bill,

If I understand correctly, the radiator support was painted by the manufacturer before it arrived at St. Louis (or AO Smith). The Judging Guides indicate that the original radiator support paint was semi-gloss black. The radiator support is then installed before the underhood blackout process, so much of the semi-gloss black core support would be covered with blackout paint, but since they weren't particularly careful, I suspect areas of the underlying semi-gloss black paint would still be visible.

About the blackout paint, I have it written in my notes several times that the original underhood blackout paint was flattened black lacquer, the same as used for the wheel wells, and it was "flat to semi-flat, definitely not semi-gloss".

Is this not correct, or where am I going wrong?

[Michael H.]

Re: C2 core support paint question clarification

Hector, Michael and Bill,

If I understand correctly, the radiator support was painted by the manufacturer before it arrived at St. Louis (or AO Smith). The Judging Guides indicate that the original radiator support paint was semi-gloss black. The radiator support is then installed before the underhood blackout process, so much of the semi-gloss black core support would be covered with blackout paint, but since they weren't particularly careful, I suspect areas of the underlying semi-gloss black paint would still be visible.

About the blackout paint, I have it written in my notes several times that the original underhood blackout paint was flattened black lacquer, the same as used for the wheel wells, and it was "flat to semi-flat, definitely not semi-gloss".

Is this not correct, or where am I going wrong?

Scott,

Yes, the core support was dipped in semi gloss black before installation, and before it arrived at the St Louis plant. (the black ones, anyway) The outer ends would have received more black during the engine compartment blackout process.

You are correct in that the paint was semi gloss. I think the confusion comes in from the description though. What is the difference between semi gloss and semi flat? Wouldn't they both describe the exact same paint?
Maybe I'm wrong but I always assumed that semi flat and semi gloss described a paint that was about the same, somewhere between gloss and flat.

[Dick W.]

[Scott S.]

Re: C2 core support paint question clarification

Scott,

Yes, the core support was dipped in semi gloss black before installation, and before it arrived at the St Louis plant. (the black ones, anyway) The outer ends would have received more black during the engine compartment blackout process.

Michael,

I just remembered a photo in the archives of a 1966 small block C60 radiator support. It was from an AO Smith car, and showed a lot of green zinc-chromate paint along the inboard bottom cross-section, the bottom reinforcements where the radiator (with cushions) seats, and the lower side mount.

This makes me wonder whether the radiator supports weren't shipped from the manufacturer in primer? If so, then AOS must have sprayed them with green zinc-chromate before installation, and St. Louis painted them semi-gloss black before installation, and then each received varying degrees of semi-flat black paint during the engine bay blackout process?

[Michael H.]

Re: C2 core support paint question clarification

Michael,

I just remembered a photo in the archives of a 1966 small block C60 radiator support. It was from an AO Smith car, and showed a lot of green zinc-chromate paint along the inboard bottom cross-section, the bottom reinforcements where the radiator (with cushions) seats, and the lower side mount.



This makes me wonder whether the radiator supports weren't shipped from the manufacturer in primer? If so, then AOS must have sprayed them with green zinc-chromate before installation, and St. Louis painted them semi-gloss black before installation, and then each received varying degrees of semi-flat black paint during the engine bay blackout process?

Scott,

The supports that were installed at the Smith plant were primed with green zincrom coating. Those installed at the St Louis plant were coated black.That would explain the green peeking through on some supports but not others. That's why I said "the black ones anyway" in my previous post.

[William C.]

Re: C2 core support paint question clarification

I'd say that is a pretty good assessment.

[Scott S.]

Re: C2 core support paint question clarification

I think the confusion comes in from the description though. What is the difference between semi gloss and semi flat? Wouldn't they both describe the exact same paint?
Maybe I'm wrong but I always assumed that semi flat and semi gloss described a paint that was about the same, somewhere between gloss and flat.

That's a great question. I understand what you mean, that semi-gloss (i.e., half-gloss) ought to be the same as semi-flat (i.e., half-flat). My thinking was that semi-gloss literally emphasized the "gloss" aspect, while semi-flat emphasized the "flat", so that if they were located along a number line, the two would not occupy the same "neutral" position, but be biased toward one end of the spectrum or the other.

Probably six of one, half-dozen of the other, from a practical standpoint. I remembered the phrase "definitely not semi-gloss" from previous TDB discussions, so that may have helped create a distinction between them in my thinking.

[Scott S.]

Re: C2 core support paint question clarification

That's why I said "the black ones anyway" in my previous post.

I caught that, it's what reminded me of the photo with green-zinc chromate in the archives

[Michael H.]

Re: C2 core support paint question clarification

That's a great question. I understand what you mean, that semi-gloss (i.e., half-gloss) ought to be the same as semi-flat (i.e., half-flat). .

Scott,

That sounds like a pretty good description. I suppose paint suppliers had to choose something that described a gloss/flat factor/percentage and either semi gloss or semi flat covered it.
It would be much easier than trying to describe the actual amount of gloss/flat on the can label.

"Somewhere between flat and gloss black".

I always felt the ratio of gloss/flat for under hood/engine compartment was about 50%.

By the way, I'm pretty sure it was a lacquer base.

[Wayne W.]

Re: C2 core support paint question clarification

Before they were installed, St. Louis supports were black and show no green. AOS supports are green and show no black. It appears that they came to the two facilities unpainted and were dipped in black at St. Louis, but primed green at AOS. After installation they were blacked out with the under hood process, however coverages were not total and inconsistent.

[Dick W.]

Re: C2 core support paint question clarification

Michael, egg shell, flattened to the percentage shown on the chart I posted, has a very low sheen. I always used PPG Deltron w/ PPG DX-685 in it to flatten. The thing I liked it was very easy to duplicate for the next batch.

[John H.]

Re: C2 core support paint question clarification

The radiator supports were stamped and assembled (welded) at the Chevrolet-Indianapolis stamping plant, and shipped raw to St. Louis and to A.O. Smith, where they were flow-coat primed black (St. Louis) and spray-primed green zinc chromate (A.O. Smith).

Indianapolis stamped almost all passenger and truck radiator support components, which were welded together at the assembly plants; Corvette was the only car line that received them already assembled.