I want to
start this with a clear warning this is the method and techniques
I used to paint my plane. It is not the only way. Read and evaluate
for yourself, but please don't contact me and tell me you disagree
with my methods or that they were wrong. I'm sorry I have to start
this with this caveat but this is to avoid conflict with a certain
individual who seems to know everything and disputes whatever
I write. Look and evaluate the photos then judge for yourself.
(Article continued
below. A flash slideshow should appear next.)
With that out of the
way, I will explain the process I used to paint my plane. The
first thing I must explain is that I had professional guidance
for my paint job. I used the facilities of Drew Brothers Customs
in Chandler, Arizona. Rob Drew just got his PPL last Friday. He
is now shopping for an RV 7 project. Rob has been featured in
many publications with feature articles on custom vehicles he
has completed. He guided me in my prep work. He would accept nothing
less than perfect.
I had access to two professional paint booths, $1000 spray guns,
a complete paint mixing facility, proper masking products and
a paint gun cleaning cabinet. Dupont polyeurathane was used. It
is important to use the right mixture and the proper temperature
reducer with what ever system you use.
Although I had painted many RC models over the years with similar
materials, I had never painted anything of this scope. It is very
important to get the proper equipment and instruction on how to
use it. Also purchase a system to catch moisture before it can
get to the gun. Again, get advice as to specifics. After all,
you just spent a bundle in time and money building a plane don't
skimp on the proper tools now.
All prep work was done at my house. This included properly mating
the upper and lower cowls. The cowl was initially scrubbed with
soap and water and a stiff plastic brush. I then liberally wiped
the cowl with acetone and air dried. I scrubbed with soap and
water again. After thoroughly cleaning, I sanded with 150 grit
paper. This opens any pinholes so they are fully exposed. Keep
in mind there is a difference between pinholes and pits. The pits
were filled with epoxy and micro filler and sanded when cured.
I also used Rage to fill some areas. This is catalyzed body filler
that is light and easy to sand.
I wiped the cowl down again with acetone and followed with a new
Micro fiber cloth. The cowl was blown off and tack clothed just
before primer was applied. I used Feather Fil primer and sprayed
on a light coat to take a look at the scope of the pin holes.
I found a few more pits and filled them. I sprayed on a heavier
coat and "finger painted" all of the pinholes with the wet primer.
This was repeated 3 times. The cowl was sanded nearly down to
the glass, cleaned and one more coat applied. Again, any remaining
pin holes were finger painted to fill. You can roll the primer
on but I have found that rolling could cause bubbles in the pinholes.
If you roll, make sure you know where the pinholes are so they
can be finger painted to fill.
The wheel pants were done the same way. The key with the wheel
pants was thoroughly cleaning to make sure all of the release
agent was removed. The cowl and pants are made with different
processes so the wheel pants are not nearly as bad regarding pinholes.
Both are epoxy. The wing tips are another matter. The tips use
polyester resin and a rather crappy gel coat. Same drill, clean
and sand. In a dark room, hold a bright light in the tip and you'll
see areas where the gel coat is covering voids in the resin. Break
these out to expose all of the open area. Fill with epoxy and
micro filler or Rage depending on the size. Once all of the flaws
are fixed, sand, prime and follow the next step.
When the glass work is done, it is now time to prime with the
paint primer. Two good cover coats will work. Now get a can of
spray "guide coat." It is usually black. Spray a mist coat on
the glass work. Now with 320 wet dry, wet sand with a firm rubber
sanding pad using perpendicular sanding strokes. Sand everything
until all of the guide coat is gone. You will see all low areas.
If bad you may have to do some additional filling. When done,
you will have an extremely smooth finish that is ready for paint.
The first step is to clean everything thoroughly. I used a cloth
with a degreaser liberally washing the every surface. The metal
was prepped by running my hand over everything. Any dents or depressions
were sanded with 150 grit, cleaned and filled with Rage. The area
was block sanded until perfect. The "guide coat" was used on these
areas.
Any protrusions were sanded. If a rivet was exposed I used a rivet
shaver and then block sanded smooth. The reason for this is simple.
If there is a rise in the surface the paint won't cover properly
and you run the risk of breaking through in post paint processing.
Even later polishing will break through.
A side note here, I did not fill all the rivets. This is metal
plane and deserves to have rivets visible through paint!!!! The
stabilizer is pretty filled but only because I was testing some
techniques.
Once you have the all the metal smooth, the metal has to be prepped.
This involves Scotch Brighting all of the metal with the maroon
pad. This pad is equivalent to 320 grit paper. I used a DA (dual
action) sander with a base designed for grabbing Scotch Bright
pads. This takes time. You only need to take the shine off the
metal.
Cleaning after this process is messy. Lots of paper towels and
degreaser. After you get everything initially cleaned, do it again
with a clean rags and wipe down. Do this until you can get clear
rags when wiping down. This will all be repeated before painting.
When everything was done, the plane was transported to the paint
shop. I should have mentioned, everything was in pieces for prep
and paint. Fixtures were made to hang the wings. This involved
a pipe through the hole behind the spar and supported with two
saw horse type paint stands. The ailerons/flaps/elevators and
rudder were hung for painting. Stands or fixtures were made to
support all pieces.
Once in the booth, the pressure system was activated. Everything
was blown off and cleaned with degreaser. This was repeated and
a lint free cloth followed to wipe off the surface to pick up
anything that the degreaser loosened.
All metal surfaces were primed with a self etching primer. Just
prior to shooting, the surface was blown and a tack cloth used.
The tack cloth should only lightly contact the surface. The surfaces
were coated with just enough to cover.
My paint was Dupont base coat clear coat. A sealer is used to
provide a completely consistent cover. This was sprayed on all
surfaces. It took two coats. This sealer is very light and covers
extremely well. A half gallon was all that was necessary to provide
coverage. The sealer was sprayed as soon as the self etching primer
was cured, in about 30 minutes.
Next was the main base coat. This is usually your primary color.
In my case it was Brilliant White with pearl mixed in. The pearl
is very subtle and only visible in the right light conditions.
I didn't want full pearl because it looks silver. Didn't want
that!! The entire airframe was sprayed with the white. One and
half gallons were used on the everything. I still have about a
pint remaining.
Base coat dries extremely fast. After curing, I sanded any rough
areas as necessary with 1000 grit paper to get a smooth surface.
This process takes a while but has to be done.
Masking can begin within about 30 minutes of spraying base. A
word about masking here. It is imperative that the proper tapes
be used. If you don't you'll get bleed through and the glue will
adhere to the surface. Home Depot tapes will not handle chemical
type auto paints. You will have a mess if you use them.
For all paint separation lines use 3M Fine Line. I used 1/4" for
all paint lines. This stuff is expensive but saves a ton of time
because little extra work is needed after removing. The next level
of tape is 3M masking tape. I used primarily 3/4" with ½ an 1
½ used as well. This tape is not the same as the home store stuff.
It has a different adhesive that withstands the paint solvents.
The next tip is to never use newspaper to mask. The paints will
bleed through and cause havoc. Use a quality masking paper. The
tape and paper should only be purchased at an auto paint store.
Since my paint scheme was very busy, the entire design was masked
off. I used white to separate each color so masking each color
and then exposing was fairly simple. My next main color was Viper
Red. About 30 minutes after shooting the red was covered and the
gold trim painted followed by the Dodge Electric Blue. Keep in
mind each masking detail took lots of time. The fuselage took
over 60 hours to mask AFTER the white was sprayed.
With the paint system I used each color has a "shade system" that
must be applied. This is primer type paint that insures color
consistency and appropriate brightness and hues. Fortunately,
the blue and gold used the same shade. The white served as the
shade for the red. The shade is applied just before the color.
It too dries extremely fast.
After everything was painted with all colors the masking was removed.
(The canopy and other areas that you don't want painted remains
covered!!) Even with the use of the best possible tapes small
bits of residue can remain at the paint line. A technique that
Rob taught me was to used remove the residue. It is simple. Use
the appropriate width of the 3M masking tape and press firmly
on the separation lines. Pull up and you'll be surprised how much
stuff comes up. Don't be cheap here, use as much tape as necessary.
Repeat if you see anything suspect.
The colors were sanded as necessary with 1200 grit paper to remove
any nits. Do it lightly so you don't go through the color. Base
covers well with very little paint. DO NOT SAND THE PAINT LINES!!!!
Next the fun part, clear coating. This is the area I left to the
professionals. I assisted and cleared some of the parts. The fuselage
and wings were done by Rob or one of his assistants. The clear
used was KCC. This clear is from Korea and sprays and finishes
very nicely. All leading edges and paint lines were given extra
clear.
The airframe was transported back to my house. I live in an airpark
so the hangar is just out my kitchen door. The next process was
to wet sand the surface. I used 1500 grit and a small wood block
to sand all top surfaces. I didn't bother with the bottom although
it was buffed and polished.
The purpose of sanding is to remove all orange peel texture and
give the best possible surface for buffing. After the 1500 grit,
2000 grit and stiff foam pad was to sand everything. This sounds
like a lot of work but isn't too bad. Since the surface was excellent
to begin with not much additional sanding was needed. The paint
lines were given a little extra attention.
One of my best friends helped throughout the process. As I completed
sanding he began a two stage buffing process. The first was with
a wool pad and 3M Perfect It 3000 compound. Next a foam pad and
Finesse II was used for the final finish.
It is now back in the air. As I look over the plane I can see
areas that will need some additional sanding and buffing. This
will be an ongoing process until I'm satisfied.
The finish turned out excellent and exactly as envisioned. There
are a few flaws that will be fixed. Some won't. Most people won't
find them. I'm my own worst enemy!!!
A single stage painting process can be used with excellent results.
The key is still in the prep work. Single stage paint is relatively
easy to spray. It is heavy due to the pigmentation necessary to
get coverage. Many single stage paints can be finished after curing
by sanding and buffing. Research will tell which ones.
In summary, the process was very labor intensive but very rewarding.
Much of this self imposed because of the design. Anyone can do
it. You don't need the professional paint booth I had. You can
make your own booth and get great results. Again the key is the
prep, the painting is relatively easy. Many fabulous paint jobs
have been done in garages and hangars. I'd do again it again but
would probably use Single Stage paint and a simpler design.
Please feel free to contact me if you have any other questions.
I'll be happy to assist.
The following is the full list of materials used to the best of
my knowledge and notes. Could have missed something. The total cost
of materials was approximately $2000.
1 quart self
etching primer
2 quarts white sealer
1.5 gallons of white base coat
1 quart of Viper Red (some remaining)
1 pint sealer
1 quart gold (about 3/4 used)
1 pint blue
1.5 gallons of clear
8 rolls 1/4" 3M Fine Line
10 rolls 3/4" 3M masking tape
6 rolls 1.5" 3M masking tape
3 rolls ½" 3M masking tape
Darwin N.
Barrie
Chandler, AZ
RV-7 N717EE KTLKRN@Cox.net
