My current finishing method is Certified or Randolph color with automotive toners added to get those colors no available off the shelf, talc filler/sanding sealer and final coat of Automotive Clear coat. The result has been 18/19 points under some very critical judging.
Here's the process:
Sand all bare wood smooth with 320. Apply 2 brushed
coats of Clear thinned 30%. Sand lightly with 600.
Cover all wood with .02 oz. carbon veil. Apply 2
more brushed coats of the same clear mixture. Again
sand lightly with 600.
Pour some full strength clear in a large container with a good sealing lid. Now dump in as much Talc as will stay suspended in the dope (allow about 10 minutes to settle) Next, very important step is to mix in a small amount of Black dope, just enough to make a very light gray. The very best Talc I have ever used comes from Tap Plastics. It has no odder or oils. Next, thin this mixture only enough to get it through your spray gun. I use a big ugly gun with pressure feed, they're cheap and readily available at Sears. Spray on a medium heavy coat of this stuff. Let it dry a day. Now here's the really cool part. You're gonna sand off 80 to 90% of this and you'll hardly break a sweat! This stuff powders like crazy! It took only 3 hours to sand an entire classic ship leaving only enough to fill. Now since this mixture is gray you will be able to tell the low spots and areas that need more work. No need to get out the spray gun, just spot these areas with a brush and sand. Once everything is uniform thin some clear dope 80% that right 80% and spray on a quick wet coat!
Color: Thin all colors 50 to 60% with and spray
on dry. Just enough to cover, don't worry about
shine, blushing or even being a little rough. Once
all colors are on. Spray on 2 coats of clear thinned
60%. Again don't worry about shine or blush. Lightly
sand everything with 800 wet being careful not to
sand through the clear coats. Finally once
everything is sanded CLEAN EVERYTHING WITH WINDEX.
CLEAN IT AT LEAST 2 TIMES USING WINDEX. I usually do
this procedure 4 times. Degreasers such as Prepsol
or AcryliClean don’t get the job done. What you
really want to do with cleaning is remove everything
that is not fixed permanently to the surface. The
reason for all the cleaning is I discovered that
just about all of the dust particles that end up in
the clear coat are on the plane to begin with. Very
little comes from the air. Once you have cleaned and
re-cleaned go over everything with a tack cloth
several times being careful to apply only light
pressure.
Now you’re ready for the main event. Lightly apply 1
coat of Automotive Clear. I use PPG Global
Performance System Clear D893 and D871 Medium
thinner/reducer (this is very different stuff from
the DAU 75). This is a 3-part paint, clear,
catalyst, and reducer. I use 50% reducer to get a
water thin mixture. I also use a gravity fed
touch-up gun to put on a very light but even coat.
The PPG is dust free in about 10 minutes and the
model can be handled in about 2 hours. Your plane
will shine like glass at this point and depending on
how much dust you have in your spray area you just
might be finished! If there is dust fear not. Wet
sand with 1200 or 1500 (which ever you have the
patience for) and rub out. This whole process added
9 oz. to a fairly large 750 sq. piped ship that has
a lot of fuse, rudder and cheek cowls. It only took
6 oz. for my Vulcan classic ship. While I've heard
of 4 to 6 oz. finishes by others I have never been
able to get it that light no matter how hard I try.
The weight of this is quite reasonable and very fast
and easy. Hope this helps.