paint weight and coats required

16 Sep 2003 paint weight and coats required

I thought I’d offer some insight for those of you who are interested in saving
weight on your paint job. I have learned (again, the hard way) that for a given
color, certain paint brands cover (or “hide”) better than others, and from
a weight/time/money standpoint, obviously the fewer coats it takes to cover the
plane the better. Time: 11:56:00 AM PST US
Subject: RV-List: paint weight and coats required
From: czechsix@juno.com

–> RV-List message posted by: czechsix@juno.com

Guys,

I thought I’d offer some insight for those of you who are interested in saving
weight on your paint job. I have learned (again, the hard way) that for a given
color, certain paint brands cover (or “hide”) better than others, and from
a weight/time/money standpoint, obviously the fewer coats it takes to cover the
plane the better. I knew before I started painting that some colors tend to
need more coats than others….for example I’ve heard that yellow airplanes tend
to be a bit heavier (or is this hearsay??) due to more coats needed.

Anyway my paint scheme (T-6A JPATS in USAF markings) is mostly blue and white with
red stripe. I am using Sherwin Williams Genesis series which is an acrylic
urethane (designed to replace the Sunfire acrylic urethane series). I picked
the Genesis paint over DuPont Imron 5000 (the two offerings from my local paint
shop) because it is a bit less expensive and easier to buff out any small
flaws. Being a novice painter I thought this was a good thing. But the downside
I’ve discovered is that the single-stage dark blue color that I’m using requires
at least 3 wet coats to get full color coverage. This is over a grey primer,
and I might get by with only two coats using a black or dark blue tinted
primer. Anyway it’s a real bummer because it takes more time and most of all
adds WEIGHT. I’ve tried to keep my airplane light so this is discouraging.
Several people I’ve talked to who’ve used dark blue DuPont Imron or PPG Concept
have said they only needed 1-2 coats. Dave Wilson for example (who’s nice
USAF-themed red/white/blue RV-8 was featured a few weeks ago in RV of the Week)
told me he only needed a single coat of each color, with PPG Concept). If
I had known this, I’d have used Imron or Concept instead of Genesis just for weight
savings, and ironically, might even save money since less paint is required
(even though Imron is more expensive than Genesis).

The twist according to local painters I’ve talked to is that while this is true
for dark blue, it may be just the opposite for a different color. For example,
I was told that red Imron doesn’t cover as well as red Genesis. Ah, too bad
my whole airplane isn’t red instead of just the stripe : )

The one and only advantage to using 3 coats of dark blue Genesis is that it does
have great “depth”….a really nice wet look with a single-stage paint that
if buffed out would probably rival a 2-stage (clearcoat). But the reason I would
not clearcoat an airplane–or use dark blue Genesis again–is because IMHO
the weight gain and expense and time to apply is not worth the slightly nicer
looks you get compared to using minimal coats of a good-hiding single-stage paint.

Why didn’t somebody tell me all this before I started? : )

–Mark Navratil
Cedar Rapids, Iowa
RV-8A N2D painting….crying….painting….whining…