radiator support paint

[Bill H.]

New member trying to restore 66 427/390hp to correct.
I need to paint the radiator support, what is the correct color?
my research with vette vues fact book shows both semi-flat black and gloss black. I believe its semi-flat black with gloss black radiator.
thanks

[Joe L.]

Re: radiator support paint

New member trying to restore 66 427/390hp to correct.
I need to paint the radiator support, what is the correct color?
my research with vette vues fact book shows both semi-flat black and gloss black. I believe its semi-flat black with gloss black radiator.
thanks

Bill-----

The radiator support was "semi-gloss black". Actually, I think I'd call it closer to semi-flat black, but some folks might call it semi-gloss. I think you'll find that most paints today described as semi-gloss black are going to be WAY too glossy compared to the paint originally used on these supports. The radiator was "gloss black". However, it was nowhere near a full gloss. Actually, I think it was more like what would be called today "semi-gloss".

So, I think if you use a modern paint described as semi-flat black on the support and semi-gloss black on the radiator, you'll come close to original.

[Chuck S.]

Re: radiator support paint

New member trying to restore 66 427/390hp to correct.
I need to paint the radiator support, what is the correct color?
my research with vette vues fact book shows both semi-flat black and gloss black. I believe its semi-flat black with gloss black radiator.
thanks

The absolute correct paint for your radiator support is GM's PN 1050104 (1 gallon)...but, the bad news is that paint has been discontinued for a while. Use satin black if you're using spray cans; semi-flat is too flat, and semi-gloss is too glossy. The satin gloss level is the closest match to the original GM black primer.

[Bill H.]

Re: radiator support paint

thanks that was fast, will try to find satin black locally

[George C.]

Re: radiator support paint



I don't know about judging acceptance, but I have used Krylon Semi flat black and think it looks very close to original.
Others will provide additional answers.
George
36908

[Chuck S.]

Re: radiator support paint

The good news is...from a judging perspective, none of the answers given thus far are wrong because of the way the painting was done at the factory. I can't say for all judges, but I would allow some latitude on gloss level because that is the way original cars are found.

This black primer was added to large open containers with enough volume to completely submerse the part or rack of parts. I doubt the containers were ever covered...depending on whether there was a follow-on shift or a weekend or a holiday period, that paint was probably left there to freely weather. That, plus the chance that a part may be the first after fresh makeup, may explain the variation of the gloss level that we observe on original cars.

When taken fresh from the can and sprayed, GM black primer is satin black...and that probably would represent the ideal case after a fresh fill; original dip painted parts could be flatter...they won't get any glossier.

[Wayne W.]

Re: radiator support paint

AO Smith or St. Louis. Makes a lot of difference.

[Patrick H.]

Re: radiator support paint

The good news: 1050104 is available again in reproduction.
The bad news: At Bloomington this weekend one vendor was selling it... for $150/gallon. Melrose T-tops makes it under license, so I'd check with them for a better price.

Realize that you radiator support was likely a semi-gloss, but the support was already installed in the car when it went through blackout. So, to be 100% correct the middle sections should be glossier than the ends, which should match your blackout paint color.

You asked.

Patrick

[Jack H.]

Re: radiator support paint

Plus, the rad support was installed when the body went through the paint booth so typical production received some degree of body color overspray on the exposed bottom rail (in lock step to the amount of paint on the front valance).

This changed when the radiator core support was angled back further in 1967 to accept taller radiators and the lower rail became naturally 'masked' by the front valance panel. Original cars I've looked at had different levels of exterior paint coverage on the rad support's lower rail with some exhibiting HEAVY coverage and random drip blobs....

[Chuck S.]

Re: radiator support paint

...Original cars I've looked at had different levels of exterior paint coverage on the rad support's lower rail with some exhibiting HEAVY coverage and random drip blobs....

Jack, I believe the "heavy coverage and random drip blobs" along the bottom rail to be the result of dip painting before installation. Confirmation of this theory would take a "cross-sectioning" of one of the "blobs" with a sharp knife, or bead blasting off the respective paint layers, to determine if the "blob" was mostly black at the center.

I have found your observation to be true on most dip-painted parts at the lowest area. It may not be obvious if the part is configured where there is easy "runoff". The "good news" is this characteristic allows you to figure out where the part was originally "hung" or suspended for dipping (on the opposite side); the "bad news" is that the thickened layer at the bottom of the part can be heck to remove by bead blasting.

The GM black primer was lacquer based and fast drying...it goes on thin (depending on how long it's been weathering) and "sheets" down the part really well, leaving virtually no evidence of runs until the very end as it collects at the bottom of the part. If there are structual characteristics that slow the runoff, you may have obvious runs and a very thick coating in that area. The worst I ever found was on the inside bottom of KH rally wheels...it was nearly impossible to bead blast off that black primer. Because of the way the primer sheets, it's a fool's errand to try and duplicate the runs when spraying parts that were originally dipped...you get too many runs if you put on enough material to "run".

[Bill H.]

Re: radiator support paint

My car is AO Smith. I found a lot of differences with under the car but what difference in the radiator support. The nose is being replaced soon, any other things I should be aware of for AO Smith??? (new complete nose from shemershine)

[John H.]

Re: radiator support paint

My car is AO Smith. I found a lot of differences with under the car but what difference in the radiator support. The nose is being replaced soon, any other things I should be aware of for AO Smith??? (new complete nose from shemershine)

Bill -

A.O. Smith didn't have a black dip-prime or flow-coat system; raw parts they primed were done in their green zinc chromate spray paint system (same one they used for the birdcage). The radiator support on an A.O. Smith body was painted green zinc chromate initially before it was installed, and extra effort was made during the engine compartment blackout operation to cover both the front and back sides of the support to hide the ugly green zinc chromate paint.

[Joe L.]

Re: radiator support paint

Bill -

A.O. Smith didn't have a black dip-prime or flow-coat system; raw parts they primed were done in their green zinc chromate spray paint system (same one they used for the birdcage). The radiator support on an A.O. Smith body was painted green zinc chromate initially before it was installed, and extra effort was made during the engine compartment blackout operation to cover both the front and back sides of the support to hide the ugly green zinc chromate paint.

John-----


I'm surprised that the radiator supports were not supplied to assembly pre-painted from their manufacturing source (i.e. like a-arms, trailing arms, chassis brackets, etc.).

[Chuck S.]

Re: radiator support paint

John-----


I'm surprised that the radiator supports were not supplied to assembly pre-painted from their manufacturing source (i.e. like a-arms, trailing arms, chassis brackets, etc.).

I'm thinking that they WERE the original manufacturing source.

They made the frame, they made the bird cage, they assembled the car for some of the midyears (probably not all at the same plant). It's not too far a jump that they were trying to get all the General's Corvette business they could, and were also making all the radiator supports.

But if they were having to dip paint the St Louis supports, makes you wonder why they didn't dip them all.

[John H.]

Re: radiator support paint

John-----


I'm surprised that the radiator supports were not supplied to assembly pre-painted from their manufacturing source (i.e. like a-arms, trailing arms, chassis brackets, etc.).

Joe -

The passenger car and truck plants welded up their radiator supports from loose parts and dip-primed them, but the Corvette radiator supports were made and assembled at Chevrolet-Bristol Road Stamping, and they didn't have any paint systems at all (their primary business was hoods and fenders), so Corvette radiator supports were shipped to St. Louis and A.O. Smith raw, just like all the major sheet metal stampings. St. Louis-Corvette didn't have the floorspace to dedicate for the radiator support subassembly, and didn't want the work.