Gene; I think he wants to know at what point on the firewall does the paint change from same as outside color to black. Where does the firewall become the floor I guess is the question.
Along the same line of questioning, in '46/'47/'48 was the whole body dipped in paint/primer or hand held sprayed. Then placed on the chassis, then body color. Or, body color, then chassis. What I am asking is what was the procedure in the factory for finishing the paint in the years that cover this forum? Should their be over-spray in certain area as in the later years ('50's/'60's)?
Like in the above question, was the car body on a carrier, then dipped or sprayed black then down the line the body color hand sprayed so as the, lets say firewall color would not have a clear cut defining start/stop line, but some over-spray on the black of the body underside. Or not?
Yes, I know, kind of rambling in the question, sorry.
Body dipping was not done back then. That came along in thw'60's and I believe Chrysler was the first to do so on their first unibody cars. In 1948 the paint color and primer was sprayed on at the Fisher Body plant. When the color was applied the doors and trunk lid were installed but not all the hardware was attached, Now this was just the body proper as when the body was painted and buffed and all hardware and mouldings and interior was installed at the Fisher Body plant, from there it was shipped to the Chevrolet assembly plant which was in an adjoining building.. There the body was lowered to the frame and the hood and front and rear fenders bolted in place. The complete firewall as well as the rear inner wheel wells were painted along with the body but was not buffed out so would be a duller, rougher lacquer as well as the door jambs and under side of he trunk lid. For some years and colors the front clip (hood and fenders) that was apinted by Chevrolet waould not perfectly atach the Fisher Body paint or would oxidize or fade to a different color. In the 1930's and up Chevrolet used a red primer on the sheet metal (under the colr) and Fisher used dark gray.
Sorry about my rambling but things keep poping up in my old brain. The under side of the body was in primer (water proof primer) and most plants used gray, not black. In the later years, like from 1955 and up some plants also used red. The bodies passed through a long paint booth on a carrier. This was also true up through at least the '60's. and '70's. In the later years the paint was not sprayed on by a person but rather by robots and the body was baked so buffing was not necessary. The change from body color firewaaalls to black occured in mid 1963 production.
The frame would have been painted at the frame plant. The underside and top of the fenders at the Chevrolet plant. Black under the fenders AND HOOD ....painted by Chevrolet. The underside of the floor would have been gray on your '48.Had some gloss to it,
The painting process in the movie confirms what I mentioned. One little correction. With the advent of Lucite paint buffing was no longer necessary. That is when the paint was baked to get a smooth, shiney surface.
this would have been in a couple of colors in 1956-1958 and all colors after mid 1958.
The change from nitrocellulose lacquer to acrylic lacquer allowed the body plants to use a reflow process. The body (including doors), fenders, hood were spray painted. There would be some overspray and orange peel. A special solvent was sprayed on the air cured paint and then the parts were put through a "reflow" oven. Time and temperature aided by the solvent "melted" the paint into a smooth shiny surface. As most of you will testify it also eliminated most of the cracking and crazing that occurs with the solvent evaporation paint systems.
FWIW - Acrylic enamel can also be cured and leveled to some degree in ovens or under lights. Doesn't result in the same DOI as lacquer but better than just air drying.
FWIW2 - Some parts were dip painted as early as the late 20s maybe earlier. Generally they were frames, other suspension parts, fenders, splash aprons, running boards. A few companies (I don't know of any automotive) dip paint parts today. Bed and sofa bed frames are some.
This is all interesting and I am truly impressed by all the knowledge on the paint issue but I think the initial question was about the demarkation between the under-body paint and the firewall paint.
Here's my two cents worth without getting in the science and features of paint:
The firewall was painted the body color (colour for our Britister friends) sufficiently low enough that an observer standing outside the vehicle, with the hood raised, would not notice the black or other underbody color.
There is no line between the firewall paint and general body paiant because they are the same color and all was painted at the same time. The only difference is the firewall was not buffed out to make it a high gloss.
There might be some overspray on the underside of the body from top coating. I was not in a Fisher Body Plant in 1948 so don't have personal knowledge. I suspect that once the body panels were installed and prepped a primer/sealer was applied. After further smoothing and filling imperfections the top coat sprayed on. That would include all "show" surfaces including the firewall. That process should produce overspray in some areas as well as likely a lighter coating on the firewall. The firewall would look very bad if it only had overspray from painting the outside of the body panels. It is visible whenever the hood is raised.
The reason I kind of strayed from the original question to the factory finish process was to help figure IF their/there is a specific defining line of the paint transition from outer body color to under body color. I going to guess, not exactly. Depending on who is swinging the paint gun at any specific time as to where the last pass at the bottom of the fire wall wound up. A little leeway I think.
Now, Gene, you may have stepped in it I have been told by many (on here) that the bottom of my '48 was black.
I think I'm plum lost on this here thread. I wouldn't think that the firewall paint would extend to cover the whole bottom of the car. Nor, would I think that there was a clear demarkation from the firewall paint and the bottom paint. Unless black to black.
Question: Was the 1941 cabriolet painted ... say Ruby Maroon, topside and bottom?
What a mess this has become. Don't tell me that if I choose Ruby Maroon for the project car I have to spray the bottom Ruby Maroon too. If that is the case then black she will be.
Gloow-ry Halijau. I have seen the coming of the Lawd! I need to repent soon. Do too!
Who started this stinkin mess? Meet me on Main street at high noon. I will be "packing" a ... sandwich. We need to talk. .
Look at it this way. The body was set on a movable skid and all area NOT FACING DOWN were sprayed with the color. There was no way to spray color on the bottom side because it was not acessable. Yes, there would be some overspray underneath becasue the rocker panels were exposed. On my '39 the toe board area (slanted panel the pedals come through) was not painted...on my 1950 it is. Probable due to the mountingbraces on the 1950 style body that stick out well ahead of the firewall.
We've danced around the question until I just want to give up.
Let me put it as simple as I can;
Picture the showroom of the dealership where you once workedt and imagined it was 1941. Then you have brought your Snap-on creeper into that showroom and tossed it near a brand new 1941 Cameo Cream Cheverolet Cabriolet (All Cameo Creams were Cabriolets). So I'm keeping it elementaryly simple here). Yu arfe on a 1fifteen minute break. You probably haven't been doing anything anyhow but Union Rules are Union rules. Read on.
Now you have retrieved the creeper which has rolled to almost the other side of the car, and now you have laid down on it and slid up underneath the car, right under the passenger seat. You take out a pack of square nabs and a Pepsi Cola and have a snake. You realize you are protected by the union. So, no problem. Read on.
You take a nap. Now more to the point: When you wake up, you then look up to the bottom of the car. With me? Okay, now, what color would you see? Don't tell me about the underseat heater or its hoses and clamps or the transmission. Just the bottom of the car's sheet metal. That at the underside of the back seat and the driver's seat, as well. Again, what stinkin color would you have seen?
Thanks. Now is that so hard? (Just kidding.)
Well, we are waiting with bated breath. What is the answer?
Page 27 of "A Pictorial History of Chevrolet 1940-1954" has a good pic of how the floor pans were painted. The picture is a gray tone and the floor panels are almost the same color as the oil pan.
When I got my '40 in 1964 and I saw the floor pans I thought they were mis-painted because they were gray. When I finally got around to cleaning 60 years of road and engine grime off the gray paint came off with the grime.
The vertical portion of the firewall and cowl were the exterior car color. The gray started on the slant portion of the firewall.
Hi 48wood, hope you are still with us. It has been quite a journey but I think we have arrived.
One thing that was brought to light , for me at least, is that the bottom of the '48 is gray and not black as I have been lead to believe. Thank you for this thread. Maybe even '40 through '48 was gray on the bottom? How about it Gene?
Mike, thanks for the reference. As many times that I have looked/read through that book, that picture never registered with my old eyes/brain. Thanks again.
Yes I have the picture, talked about above. However, since that is a page taken from a copyrighted book, I feel it would be wrong for me to post here. I hope you understand. I have often wanted to post pictures and text from the book as it is full of good information, but it is copyright protected.
Besides, all who have or like '40 through '54 should buy/own this book!
Wow! Cousin Dave and I spent days under my '48 convertible torching and scrapping undercoating off the underside of the body. Sure looked like black paint to me when we got down to the metal. Seriously - gray??
Dale Carter VCCA #8661 1948 Fleetmaster Convertible 1948 RHD Stylemaster Sedan Delivery 1948 1-Ton Tow Truck 1967 Camaro Coupe
I have been told by many (on here) that the bottom of my '48 was black.
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