Clear Coat: Not So New

[MochetVelo]

I often read of the "new" base coat/clear coat (bc/cc) technology, how it does or doesn't suit old cars, etc. Actually, bc/cc goes back at least to the 19th century. High-quality carriages were painted with a flat base color coat that was heavy with tint and then topped with a clear varnish. This was also a system used on cars. I have a 1957 book on vintage car restoration [The Restoration of Vintage and Thoroughbred Cars]. In chapter XVI, "Body Painting", the two options offered are "cellulose" (nitrocellulose lacquer) and "coach paint," the latter being a enamel brush job finished off with a clear coat of varnish. Boats were also often painted this way.

Want to read a 1911 book on carriage and wagon painting that also applies to cars? Try this. (It also has a cool feature: click the "speaker" button on upper right, and your computer will read the book to you while you do the dishes).

Phil

Edited February 24, 2011 by MochetVelo (see edit history)

[barry22]

Tell me about it. I owned a 1956 Plymouth 40 years ago that was in need of a paint job, as no amount of wax would help bring back the shine. I bought a gallon of clear Dupont enamel and brushed it on the car using a fine bristle brush. The paint flowed extremely well making any brush marks barely perceptible and resulted in a finish that looked no different than the wet deep gloss seen on new base coat/clear coat paint jobs of today. Even professional painters were surprised by the results.

[KenHupp20]

Phil, That book is excellent ! A very good find, thank you for posting it .

Ken

[20Premier]

How should the type of paint be chosen for a high end 1920 vintage car, or the is color the most important consideration? How about care and maintenance of the finish?

[Guest De Soto Frank]

How should the type of paint be chosen for a high end 1920 vintage car, or the is color the most important consideration? How about care and maintenance of the finish?

Prior to the introduction of "Duco" lacquer around 1924, most non-black cars were painted with either some sort of enamel or "varnish"...

In this day and age, when the original materials / methods are long -gone ( or prohibited for environmental reasons ), the usual approach is to use a more modern finishing "system" that will give an appearance similar to the original finish.

Both color choice and type of finish ( sheen, gloss / flatness ) are

important.

Original sales publications may provide some clues as to colors...

Phil's link to the 1911 book probably provides appropriate background for low-production builders such as Premier prior to the pyroxilyn-lacquer / spray-booth era...

A "sporting body" such as a roadster would probably tend to wear more colorful paint than a formal sedan... as a general rule of thumb...

[Guest De Soto Frank]

As for the base-coat / clear-coat concept, it does go back to the 1930's, at least for faux wood-grained finishes...

The metal parts first received a "ground" coat, usually lacquer or enamel; once that cured, the "grain" was applied as a ink design, either brushed-on, or roller-transferred from etched plates, then once that had dried, a coat of clear lacquer was sprayed-on to "fix" or protect the ink graining from physical wear and to impart a glossy sheen, like one would get from fine furniture.

But modern BC / CC finishes can look "odd" on a pre-1980's car or truck...

[Guest Jim_Edwards]

As for the base-coat / clear-coat concept, it does go back to the 1930's, at least for faux wood-grained finishes...

The metal parts first received a "ground" coat, usually lacquer or enamel; once that cured, the "grain" was applied as a ink design, either brushed-on, or roller-transferred from etched plates, then once that had dried, a coat of clear lacquer was sprayed-on to "fix" or protect the ink graining from physical wear and to impart a glossy sheen, like one would get from fine furniture.

But modern BC / CC finishes can look "odd" on a pre-1980's car or truck...

"Odd" is a nice way to put it. Just flat looks wrong is a more direct and accurate way to put it.

I just recently saw a '59 Ford retractable that had been repainted by someone who obviously really knew what they were doing. The paint had the correct luster for a '59 car. Absolutely beautiful. Unfortunately the owner wasn't present and the guy that owned the shop where the car was at the time didn't know who had done the paint job. You can bet I intend to find out. Best paint job I've seen in years!

Jim

[MochetVelo]

I borrowed this from the MTFCA (Model T Club of America) Forum. It refers to the 1915 photograph below of Ford's "Flow On" paint system. They are actually hoses that squirt a curtain of finish onto the car from holding tanks above. The run-off is recycled.

"To be 100% correct, the photo shows the application of the first coat of (clear) varnish. The color (black) has already been applied. By this point, the reddish-brown primer and base coats of black have all been sanded and "are void of runs or imperfections". Any runs in original paint are most likely to be along the bottom of the body from the application of clear varnish in this step.

And yes, the originals WERE base-coat/clear-coat during the 'black era'."

Phil

[Rusty_OToole]

I thought Fords were painted with fast drying black Japan enamel originally used on chassis and fenders?

[MochetVelo]

It's a myth that Ford chose black because it was faster-drying, even though it's been repeated by many noted historians. The tint or colorant of a paint doesn't have much to do with drying time. That's a factor of the solvent and vehicle (turpentine and linseed oil, for example). Check here to read more. The Model T clubs have published definitive research on the subject.

Phil

[Rusty_OToole]

The story I heard was that once mass production took hold, the painting process was a bottleneck. It took too long to build up coat after coat of paint and let it dry. Ford asked someone in the plant "What is the fastest drying paint?" the reply, "The black enamel we use on fenders and chassis" "use it to paint the whole car" "But what if our customers want different colors?" "Tell them they can have any color they want as long as it is black".

This black enamel was used on a lot of cheap tinware at the time. My mother kept important papers in a black tin box passed down from her grandfather, it was finished in a tough but dull black, more of a semi gloss or satin finish really. I believe this cheap tinware was painted with something called black Japan enamel because it had a lot of Japan dryer in it.

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Later: I wasn't far wrong. See this Wiki on black Japan paint. It used an asphalt base which accounted for its flexibility and toughness. This is why it only came in black. It also kept the cost down.

According to this article it was possible to paint a car in black and have it cure in 48 hours while it took 14 days to paint any other color. They even give the formulas Ford used.

PS I think they waited less than 48 hours for the paint to dry, either they baked the bodies or they assembled the car before the paint was fully cured but somehow I doubt they waited 48 hours.

http://en.wikipedia.org/wiki/Japan_black

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Still later. Apparently the black japan paint originated in Pontypool Wales in the late 1600s.

http://en.wikipedia.org/wiki/Pontypool_japan

Edited March 10, 2011 by Rusty_OToole (see edit history)

[MochetVelo]

Yes, that's the story you'll read almost everywhere, Rusty: "The black color dried faster." It's not true, though. The Model was put through ovens to cure the paint (4 coats total, I think), so they didn't sit around for long between coats. Ford could have used any color available at the time. In fact, the early T's were available in several colors, but the black proved the most durable and economical. Ford used about 30 formulas of black in each car on the various parts according to how they were applied and used. The formulas still exist at the Ford Archives. I think the MTFCA published a nice research paper on the subject. That's where I got this information.

The thing I didn't know was that the Model T was clear-coated!

Phil

[Rusty_OToole]

According to the formulas in the Wikipedia article, it wasn't. There were 2 formulas of black paint used for Ford bodies, a first coat which contained asphalt and carbon black as pigments, and a shiny finish coat with asphalt only. The car bodies were given 2 coats of paint then baked at 400 degrees.

It may be that the baking was the key to the fast drying and only the black japan paint would stand it. Also the black japan paint was tough and durable, as well as cheap and fast.