Black Paint Sheen

[Ray C.]

Hi!

I am trying to determine the amount of flattening agent to use to achieve a correct (close) sheen for all black painted components. I under stand that GM used multiple paint suppliers and the paint sheen would vary by manufacture, but I would like to establish a standard. If full gloss is 100% sheen, would semi-gloss be 50% sheen and where would semi-flat fall on the scale of 1 % (flat) to 100% (full gloss) sheen? (1963 SWC)

Thanks for any help!

Ray

[Mike M.]

Re: Black Paint Sheen

This site may have the information you need. It has most colors for the year of car with there percent of gloss ect. Mike

http://www.autocolorlibrary.com/cgi-bin/search/search.pl

[Michael H.]

Re: Black Paint Sheen

That's a really good question Ray. This paint issue has been kicking around for a long time and no one really seems to know exactly what the answers are. As you mention, there are several different levels of flat/gloss for the black painted items and there are several reasons for this difference. Most of the "vendor" supplied parts were supposed to be coated black and several used a GM supplied paint but the GM spec's were not exactly clear as to the exact amount of flat/gloss so the vendors that used something other than GM material may have strayed from the intended target.

As far as the semi gloss/semi flat issue, I'm still not sure if there's a difference. It's the "half full/half empty" glass of water deal all over again. Technically, they should be the same but some paint sources seem to think semi gloss is closer to gloss than semi flat. If you spray test panels of several different manufacturers semi gloss or semi flat, some of the semi flats appear to have more gloss than the semi gloss. I thin it all comes down to trying to match the original gloss level on any given part.

I always used a number system of 1 through 10 for gloss level but a few months ago, Jack Humphrey mentioned that he used a 0 through 100% system that made much more sense. Semi gloss would then be 50%. Semi Flat should also then be 50%. From there, it's a matter of deciding which parts were coated with which percentage of flat.

The last part of the problem is, some parts were spray painted and others were dipped. If you use the exact same paint for a spray operation that you used for a part that was dipped, the dipped part will come out with more gloss than the sprayed part. Good example is the engine compartment blackout. The gloss appears to be in the range of about 40%, yet the same paint on dipped steel parts would appear to be roughly 60%.

In the end, there is no standard gloss/flat level between vendors and it gets even worse. If more than one vendor supplied the same part to GM, they may well be quite different in the amount of gloss because they may have used different sources for the material.

The only "full gloss" items under the hood that I can think of off hand would be the air cleaner base and anything else from AC Delco, including the main can of a fuel injection air cleaner. (the "s" tube was semi gloss, dipped) There may be other items that were full 100% but almost everything was in that 50% range.

Michael