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+--- Thread: Enamel and Cellulose paint history/practice (/showthread.php?tid=9417)
Enamel and Cellulose paint history/practice - JonE - 12-06-2024
Been looking in the Source book and see the 1927 or '28 instructions for new use of cellulose on cars as the paintshop manufacture process started; spraying etc. Wondered whether people can see the difference between the two... i.e on historic paintwork remaining?
I notice that Craftmaster coach enamel is actually cellulose so I now wonder what the term 'enamel' actually means. I've been trying some (Royal Warrant!) coach enamel which is thinned with white spirit and incredibly slow drying/setlling.
I'm guessing that historically, cellulose came in for reasons of practicality and efficiency as production broadened. Has anyone experience of both types, for brush painting?
RE: Enamel and Cellulose paint history/practice - Adam Brown - 12-06-2024
Craftmaster Coach Enamel is 100% not Cellulose they are two totally different things.
Historically early motors were probably largely painted with paints based on linseed oils. This was a continuation of the practice from carriage building days. Cars of course led to mass production and the requirements for faster drying products. Nitro Cellulose was the widely adopted answer, though faster drying enamels also existed (I am not sure what Model T's were painted with but they were sprayed). 2k followed as a faster drying, harder more resilient paint and was adopted before it was fully matured as a product but has over time also evolved.
What you have the option of today is largely compromised one way or another by the restriction on ingredients. Cellulose is a niche product which can only be sold for historic or specific industrial use and as such nearly every Cellulose on offer is not to automotive grade. Enamels (like Craftmaster) are Synthetic and have been for some time (the technology is over a century old). Oil based paints are nearly non existent.
There were once upon a time also version of Cellulose that would brush but these are long gone.
I run Craftmaster. We are very specialist in what we do, we don't compromise quality for price we just try to make the best possible product and the price follows on from that. There are cheaper products that work to varying degrees under varying brands but most aren't specialist, they are a rebadged product amended slightly usually from something industrial. Our Cellulose is to a true automotive grade.
I've heard tell many cars were sprayed with cellulose or something similar from the 20s, but refinishing shops would still be largely hand painted for many years to come. Looking at evidence and in discussion with others I believe that all run of the mill Austins would have been sprayed in house, but commercials would have left in primer for finishing elsewhere as liveries varied greatly with such users, it is likely many of these would have been hand painted.
RE: Enamel and Cellulose paint history/practice - Chris KC - 12-06-2024
Not much I can add to Adam's reply but I'm curious Jon, what paint is it you actually have, and does it really say to thin it with white spirit (as opposed to clean up with same)?
RE: Enamel and Cellulose paint history/practice - Howard Wright - 12-06-2024
Hi Jon
To back up Chris’s query. I’ve just brush painted my van using Craftmaster coach paint. No need for thinners unless you are spray painting and then use the special stuff that Craftmaster sells. If you dilute it you get runs.
Cheers
Howard
RE: Enamel and Cellulose paint history/practice - Peter Naulls - 12-06-2024
So is the suggestion Jon that prior to 1927 they didn't spray the cars? or that they didn't use cellulose?
Just to complicate things further I noticed in one of the Austin factory films of the 1930s that the wings were described as being "dipped in black enamel". Difficult to imagine how they got a good finish.
The term "enamel" seems to have been used for cellulose, spirit based and synthetic paints at various times. I had a couple of tins of cellulose enamel in the cupboard until recently.
RE: Enamel and Cellulose paint history/practice - Tony Griffiths - 12-06-2024
(12-06-2024, 09:10 PM)Peter Naulls Wrote: So is the suggestion Jon that prior to 1927 they didn't spray the cars? or that they didn't use cellulose?
Just to complicate things further I noticed in one of the Austin factory films of the 1930s that the wings were described as being "dipped in black enamel". Difficult to imagine how they got a good finish.
The term "enamel" seems to have been used for cellulose, spirit based and synthetic paints at various times. I had a couple of tins of cellulose enamel in the cupboard until recently.
There is a good chance that "dipped in black enamel" meant stove enamelled. i. e. dipped and then heated in an oven at 120c.
I believe that in the "paint process" multiple coats could be applied - though I doubt that. in a production process, they would have been rubbed down between. I understand that early cars (1923-24) had stove-enamelled wings as did the Ruby - but that might not be true, unless we can unearth some solid evidence. Stove enamelling is still carried out - https://goldburnfinishers.co.uk/stove-enamelling/?gad_source=1&gclid=CjwKCAjwjqWzBhAqEiwAQmtgT_97s2AQ9Co5ZKH1_8Jf8kZ32JZb76KLK1voEzK6vWFY4cEaVHvT9hoCmSwQAvD_BwE and https://blastreat.co.uk/stove-enamel/ and https://www.keeppowdercoating.co.uk/stove-enamelling/index.html There is also 'Vitreous Enamel', a rather different process: http://www.trico-ve.co.uk/contract-enamelling/
RE: Enamel and Cellulose paint history/practice - Chris Garner - 12-06-2024
In a publication " On the Road and in the Making " describing the manufacture of early Sevens, it states:
The process of painting consists first of spraying on a suitable undercoat and then of " flowing " on a coat of enamel. The body is then conveyed on a runway through a heated tunnel, along which it travels, to emerge at the other end two hours later dry and ready for the attachment of wings, running boards...etc.
I'd be interested to know more of this " flow-painting.
RE: Enamel and Cellulose paint history/practice - JonE - 12-06-2024
Good to read Adam's post thanks. I only posted that ref. to cellulose as a present ebay listing was (cut and paste from ad follows) "Craftmaster Coach Enamel is high quality, highly pigmented paint designed specifically for brush application is a highly authentic cellulose paint designed specifically for Automotive Use. In the right hands comparable results can be achieved to spray finishes. Please note product takes 6 weeks to fully harden so whilst rubbing down and overcoating can take place within 24hrs if you intend to cut back and polish you should wait until the end of the 6 week period
Best results are achieved with the addition of our PPA Brushing Additive. This product can also be sprayed with the addition of Synthetic Thinners"
...so that confused me further but perhaps is slightly miss-cut text, after reading this post?
I was certainly surprised to come across the Wilson's paint (Exmouth) with them saying "just use white spirit". I'm guessing their royal coaches painted are old horse drawn things, but it certainly spreads well - I've just brushpainted direct on steel metal without primer, as per what it feels like the original paint was from the panels I've cleaned back. (I'm not going to do that on aluminium, but my gut feel is that cheap cars like the Seven had a lot, lot less paint on in the twenties). Advice was just AAAA wirewool before second coat, but then don't do anything afterwards. Think there was something about 10% white spirit thin if needed.
Just looked at Source book - p116 - it's referring to a changed cellulose process for 1927... not a new process. One picks these snippets but it's difficult to find actual evidence, as others above refer to. One of the Rinsey Mills very early cars LOOKS stove enamelled (in its degree of reflectivity), but is it original paint?
RE: Enamel and Cellulose paint history/practice - andrew34ruby - 13-06-2024
Did Austin use black primer? When removing all paint from my 1934 Ruby the green 1950's cellulose was on top of the original black gloss, but was black right back to the bare steel. Every part of the car was black through and through.
RE: Enamel and Cellulose paint history/practice - Peter Naulls - 13-06-2024
The later cars I've worked on have all had brown primer.
Period photos of new Sevens, especially the early ones, showed paint finishes quite different to what we have today.