I prefer working with gray primers because they provide the best
range of highlights and shadows to scrutinize for imperfections.
For Primers, I prefer Rust-Oleum
Stops Rust Automobile Primer, Light Gray Primer 2081
Premium Filler Primer . These are thick, coarse primers, that dry
quickly and sand easily. The only downside is, I feel as though
my recent rockets have had a lot more chips than earlier rockets
that used a Krylon
Krylon makes a sandable primer, although I would debate just how
sandable it is. It gums up my sanding sponges almost immediately.
Recently, I did finally try Kilz primer on test material. It's
a little startling, because is comes out at least twice as fast
as other primers. It bubbled and clumped and produced a rather uneven
finish. However, it does seem to hang on wherever it lands and appears
to be very durable. I used it on a PML Intruder
I've experimented with Krylon, Rust-Oleum and Dupli-Color white
paints. Of the three, I personally prefer Krylon. I've been able
to spray other brands over it.
Two different cans of Rust-Oleum white, two different rockets,
same results. I've have problems with the Rust-Oleum white never
drying and had to strip the paint down to the base. This phenomena
seems to be isolated to their white paint. I highly recommend shaking
the can for about five minutes. Before starting the paint session,
spray in to the air for about 3 seconds to clear any unmixed paint
in the nozzle.
Dupli-Color's Super White was unevenly chalky. This might have been
humidity. Too many whites to choose from.
There are varied opinions for and against the use of clear coats.
My opinion is that benefits justify their use.
- Additional protection and sealing
- Enhanced appearance
- Easier to wax
Clear coats are the softest of all acrylic enamels. They must be
handled and stored with great care until they have cured sufficiently.
For the beginner, I would recommend Krylon. It's simple, forgiving
and reliable. I personally prefer working with the Rust-Oleum or
Dupli-Color clear coats.
Practice and test paints on something other than your rocket
Know how your paint or combination of paints are going to behave
prior to painting your rocket. The cheapest test material I've found
is empty aluminum soft drinks cans.
Some paints tend to be a little bit "puffy". As the solvents
evaporate, the paints contract. If you get runs in your paint, give
it a couple of days to cure. Patience is a virtue. A lot a problems
will fix themselves or at least be less significant. If you really
need to speed up the curing process in specific areas, you can hit
them with a hair dryer. Be careful though, heating up the paint
can make if soft and vulnerable to other damage.
After Painting Care
One final time I'll emphasize that spray can acrylic enamels are
rather soft paints and actually take weeks to cure completely. Store
the rocket vertically on a rocket stand for several days allowing
the paint to cure further. Do not allow the paint to rest against
anything. As a side note, I would never hang a rocket with acrylic
enamel from the ceiling. Whatever you hang it with will gradually
cut into the paint.
After a day or two take your rocket outdoors and let it get a suntan
for about half a day. The goal is to accelerate the the curing process
by baking the solvents out of the paint. A word of caution, while
the rocket is baking, paint can get very hot and bond to other parts.
To prevent this from happening, keep the individual components,
nose cone, payload section, and booster separated. Rotate the rocket
regularly to get and even tan. Be sure to use a stand that won't
blow over ruining all that fine work.
Ideally, I would let a rocket cure a month or two before flying.
The day before it's maiden flight, it gets a coat of Meguiar's Cleaner/Wax
for just a little more protection from the various chemicals, sun
tan lotion, perspiration, grease and exhaust, it will get exposed
to. Wax should be applied and removed with a clean cotton cloth.
Synthetic fiber can scratch.
Transport the rocket to the launch wrapped in cotton towels to
prevent it from getting scratched by seat belts.
Static electricity and lint
Probably the biggest problem with getting a good finish is static
electricity and lint. My solution is the wrist bands electricians
use to discharge static electricity. Plug it into a wall socket
and tap it to several areas on the nosecone or airframe to help
discharge that nasty static cling. Safe, nontoxic, nothing to replace
or refill and it doesn't hurt the environment. Afterwards, I use
a tack cloth to remove the lint. I can't say it works very well,
but it can't hurt.
Heating Up the Can
There are several sites that suggest heating up the spray cans in
warm water for a couple of minutes to improve the paint flow. Warm
is a fairly ambiguous term and I really wouldn't recommend this
until some one publishes safe temperatures and times. Over heated
the can will explode. This is an accident waiting to happen. No
paint job is worth risking your health. Live to fly another day.
Paint Finishing - NARHAMS' exceptional paint article.