<<That one I can't answer, but I'd be REALLY surprised to hear that
it "can't be matched.">>

"Can"t be matched" and "is it worth out time and money to match it?"
are two slightly different things. I am not a professional coloursit
or paint chemist and I have never played one on TV or even on the
internet, but I do enjoy playing with paint and have been doing it for
a while

Lead free paint seems to have it's own colour space very slighly
different to full strength leaded paint. I think at least part of the
problem with colour matching is that all the modern substitutes for
leaded pigments don't have quite the same covering power. Real Flake
White for example made a really solid opaque white and modern
substitute combinations of titanium and zinc oxides are only the next
best thing

Of course the use of lead based pigments raises another question -
how old is the paint chip you are trying to match? The colour of lead
pigments changes with exposure. Sulphur in the atrmosphere -
something very likely to be found around STMFCs - will cause lead
based pigments to change colour over time with some combinations of
pigment and environment tending to black over time; lead oxides which
are white become lead sulphides which are brown the blackish. For
example look at the white paint buildings near the tracks in steam era
photos - that greyish colour wasn't just soot, but could often be an
actual change in the pigment

A coat of varnish helps seal the outside surface and slow the process
due to external sulphur, but it can't help if the sulphur compounds
are included in the paint itself. Mixing the flake white with some
other pigments could also affect the colour over time. Artists and
painters would be aware of many of of the known reactions - mixes of
flake white and vermilion and ultramarine were avoided by water
colourists. Cadmium based pigments are another set that can cause
problems with lead

So just what colour are we trying to match?

Aidrian

So just what colour are we trying to match?

Aidrian

What I was looking for when I wanted a paint alternative to Accupaint (and >>really<< need now!) was
the light gray-green used in the horizontal band on ERIE passenger equipment. Some Express
passenger equipment, which may have been hauled by steam, but was certainly used within the list's
era limits, was painted this way ( so we're a least lightly touching list content here). It is a
color that EMD never used on any other road's power, so it's not like there is a secondary market
for it.

I spent a couple of months working with relevant colors of Scalecoat 1, attempting to develop a
repeatable match to a valid sample I have somewhere, and it came very close but was slightly too
dark. It was measured in drops, a standard unit of measure. When I tried to add white, Scalecoat's
white contains quite a bit of blue, which whacked everything out of shape. VERY frustrating.

SGL





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It was measured in drops, a standard unit of measure. When I tried to add white, Scalecoat's
white contains quite a bit of blue, which whacked everything out of shape. VERY frustrating.

A good place to start with older grey-greens is to assume that it is likley to comprise a basic mix of black, yellow and white which may be adjusted with a few more expensive pigments. The original paint was probably lead based, and lead white would have been a key ingredient.

If the Scalecoat white has a slight blue cast - not unusual as this is a common trick to counter yellowing - increasing the amount of yellow in your mix may help compensate for this. If am am trying to removea blue cast I usually try to work with yellow ochre shades as the pure saturated yellows can shift the resulting colour too far towards green.

I am not sure I can offer much more for Scalecoat, but I do keep a few bottles of Ceramcoat and Liquitex acrylics for adjusting acrylic model paints.

HTH

Aidrian

Many military vehicles use an olive green-type color. Adding white to lighten usually doesn't work well, as you found. The solution that has developed over the years is to use a WW II German color called dunkelgelb or dark yellow (which is really a light tan) instead of white.

KL