Re: Digest Number 1870


Don Valentine
 

Quoting Thomas Olsen <tmolsen@...>:

In regard to Mal's reference to Scalecoat painted engines from 30 years
ago: the toughness of the finish is because the Scalecoat used 30 years
ago had a lead base which has long since removed from the paint
formula. I have engines that were painted back in the middle 60's and
70's with the lead-based Scalecoat and the stuff is almost
bullet-proof. This seems to be true for all the paints manufactured
today.

The first thing that I do before putting on the finish coat is to prime
the piece with Floquil zinc chromate. After the prime coat is dry,
then
I finish the job with Scalecoat. I have always used Scalecoat-I on
everything, be it brass, plastic or urethane and have never had it
damage the plastic or urethane surface. The secret is to spray it wet,
but not so heavy that it runs. In mixing for spraying, I use a 50-50
mix of paint and thinner. The nice thing about Scalecoat (whichever the
version) is that it is the most forgiving paint that I have ever used.
snip

So, it is just a matter of watching what you are doing and taking care
to properly thin the paint and watch how heavy your paint stream is
coming out of the brush. Actually, if you can raise the air pressure
up
to about 50 psi, you will still cover what you are painting adequately,
but will actually use less paint. And if you are baking a brass piece,
make sure you have the right temperature, as Mal has said (150-170
degrees) and you will be okay.

As I have noted several times before on this list, I have used
Scalecoat in much the same way Mal & Tom have described since 1968.
The one thing Tom has described that I do NOT do is use Floquil zinc
chromate primer for ANYTHING! My complete dissatisfaction with that
wholly unnecessary material is what prompted my discovery of Scalecoat
as a far better method back in 1968 to begin with. Fellow listee Andy
Miller had instructed me on how to paint brass models the "Floquil way".
A new Gem CPR class D-4g 4-6-0 was prepared, primed with the detail hiding
Floquil zinc chromate primer and then painted, also with Floquil. While
Andy and others said the resiults were fine, I was far from satisfied. The
floquil paint of the day had enough of a tendency to hide detail on its own.
I suspect much of this was due to a pigment not ground fine enough but other
may have other ideas about that. But if coarse pigment in the paint itself
were not bad enough the zinc chromate primer was the kiss of death. I still
have the CPR D-4g as well as another painted the "right way", with Scalecoat.
The two are used to show why I have never used Floquil for anything but
weathering since. Weathering can be done with a number of colors and the
fact that the pigment may be more coarse doesn't matter unless one goes
overboard as another way to hide detail is with over-weathering.

This said, I will admit to having avoided Floquil products for years,
accept as noted. Thus their zinc chromate primer may have "improved" in
the interim. But the question must be raised as to why anyone would use
a product such as the zinc chromate primer with another product like
Scalecoat that was specifically designed to be used WITHOUT the awful
primer? I would also suggest keeping oven temperature used to bake
Scalecoat to a MAXIMUM of 150 degrees and, again, with three hours
minimum for the first coat and one hour for each additional coat. That
is all that is needed so why risk more? And if it makes you feel any
better, Tom, I, too, have created a brass "kit" from overheating an oven.
This was with a Trains, Inc. brass GN express reefer back in 1972. The
oven was a gas one with a questionable temperature control. That problem
was cured by never using anything but an electric oven since!

Enough said, Don Valentine

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