|The MGA With An Attitude
PAINT COLORS, NON-STANDARD for MGA - PT-150F1
FEENEY GREEN - Search for the optimum BRG
This article was written by Ray Feeney, California, USA, posted on the MG Enthusiasts' BBS, MGTD, in October 2006, and is reproduced here with permission of the author.
British Racing Green -- A History and Formulation discussion
I have spent the last six months gathering a fair amount of information on British Racing Green from a variety of sources and I thought I should summarize it here for the benefit of all. I do have quite a bit more information if anyone feels that they want some of the more obscure mythology.
First, it is well documented that BRG is a range of colors - both for aesthetic reasons and because it visually varies significantly with small changes of formulation. Before the advent of repeatable paint mixing methodologies and more stringent controls on factory colors, the variations often occurred within the same brand and automotive model. In addition, painting techniques and base/pigment choices have evolved or become obsolete. Lead based pigments are no longer an option - therefore formulations exist for many of the variants, but the ingredients do not.
My painter uses PPG paints exclusively and prefers the DCC single stage Acrylic Urethane. Specifically PPG Deltron Concept 2K Urethane so all of these formulations listed here are for one quart quantities of PPG DCC. And I should acknowledge the help of the people in the Color Science Lab at PPG for their responsiveness as I went through this lengthy exercise.
I started off by gathering samples of BRG painted metal items and by accumulating as much of the history as I could gather. I had the computer system read about 15 metal samples (the underside of boot lids seemed the best candidates) and then I selected a few formulations and had these mixed up for testing. Once I had a candidate formulation, I had a sample sprayed onto a 6” x 9” primed metal sheet. These were then color sanded and waxed so that the entire process truly emulated the intended restoration approach. As I started changing the formulations, I learned a few things. Removing some of the black in the formulation, really gave a good insight into what kind of underlying green any particular approach to BRG was based on. When a percentage of the black is removed from the typical GN25 MG green formulation it shifts towards a very earthy muddy look -- trending towards a military type green. Perhaps there is something to the apocryphal story that after WWII the motor vehicle industry in England was well stocked with ingredients for military green paint formulations and that black was added to create a new family of colors that became known as British Racing Green.
In addition to using the computer paint system to read (and attempt to understand) the colorimetry of surviving period painted automobiles, I gathered information about what people have been using for BRG on the typical bulletin boards and forums. While there have been many different approaches used to pick a BRG for individual projects, there do seem to be a couple of trends. Mike Goodman (who recently retired after almost 50 years of MG repairs and restorations) painted many MGTC and MGTD cars in a BRG formulation that was felt to be close to GN25. This PPG code was 44644 (which is called Cypress Green) and it was a Volvo P1800 sports car color with a Volvo color code of 110. Later on, the PPG code for MG GN25 (which was 43342) was switched to the same pigments and sometimes the exact same formulation is used. If one requests the formulations for 43342 and/or for 44644 from PPG you are never quite sure what you will get -- but they can both result in:
DMC900 Strong White 88.6
DMC936 Blue Shade Phthalo Green 668.0
DMC902 Carbon Black 217.5
DMC905 Lemon Chrome Yellow 172.1
Unfortunately, DMC905 is a lead based pigment and is no longer available (at least in California). This above formula is what Mike Goodman used for years. To my eye, it is a very slight bit too yellow green and not quite dark enough.
The other most common BRG formulation is Jaguar HEN or Jaguar color code 701. (Used on 1987-1990 Jaguars) This is PPG color code 46169 and results in a formulation:
DMC937 Green 605.1
DMC901 Strong Black 341.5
DMC908 Yellow 115.7
DMC904 Blue 31.4
DMC900 Strong White 24.9
This is a very dark BRG with a strong bluish tint. It can require a second look to not think it is black - particularly if it is not in direct sunlight. This is a true Jaguar color and quite popular on XKE’s and on XK120 and XK140 cars. To my eye, on cars like an Austin Healey or an MGA it looks too dark.
In 1991 Mazda built a commemorative edition of the Miata and it was painted British Racing Green. It is Mazda paint code HU. Since it is a more recent automobile, the color formulation is available from many manufacturers. The PPG code is 47037 (called Neo Green) and the DCC formulation is:
DMC937 Green 671.2
DMC901 Strong Black 396.9
DMC900 Strong White 41.4
DMC919 Yellow 5.7
DMC918 Yellow 1.0
This is a gorgeous dark BRG and it looks great on more modern British sports cars. For instance, I believe it is the best choice for a British Racing Green colored Jensen Healey. (Be careful not to end up with the 2001 special edition Mazda Miata British Racing Green. The 2001 version is a modern metallic color and not appropriate for anything.)
One thing to notice is that the more commonly chosen BRG formulations listed above have either four or five pigment tints used in their formulas. It appears that with BRG this is critical. When I used the computer to “match” the period painted samples of BRG that I had collected, I often got a suggested formulation with 12 or more tint ingredients. The color may have come out a match, but the paint was dull and lifeless with no kick. I gave up on the computer system and set about adapting the PPG codes 44644 and 43342 into a modern lead free formulation. In the course of all this testing, we mixed up 19 different formulations. Each was mixed with the hardeners, sprayed, sanded, waxed and evaluated.
A few observations. BRG covers a very subtle range of acceptability. It is easy for the colors to get muddy, lifeless and drift towards military olive drab. It is easy for them to slide into a blue black that is almost not a green at all except under very direct sunlight. All of these colors are attempting to emulate obsolete formulations that are in turn revised as the laws governing paint continue to change. The revised formulas that target the BMC and British Leyland colors tend to go too yellow or they go dull. The revised Jaguar type colors tend to go too blue.
After about the 10th sample, probably most people would just say “Pick something”. I am sure that is what my local paint store felt. But I work in the motion picture industry adjusting subtle color for a living. This became a personal challenge and a goal to sort through. I now have a formulation that I am happy with. It is not quite as light as the color Mike Goodman used but I think it is more correct. In bright sunlight the color shifts from a green with hints of yellow to a green/blue depending on the angle of the sun. With the painted object between the viewer and the sun, it is very green with some earth yellow but with the sun at your back, it is quite dark and somewhat blue. I think it does everything that British Racing Green is supposed to do. The PPG DCC formulation is:
DMC900 Strong White 54
DMC936 Blue Shade Phthalo Green 700
DMC902 Carbon Black 170
DMC986 Organic Yellow 170
DMC919 Inorganic Yellow 35
I think an MGA painted in this color would be gloriously stunning. I am currently doing an MGTD in this formulation. I would encourage anyone thinking of using British Racing Green on a MGTD, a MGA, or even an Austin Healey BJ8 3000 to mix up a quart of this and give it a try.
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