Preparing and Painting the Kit Version
This section is written to cover painting and detailing of fiberglass components using in Century’s scale helicopter kits.
Some included references may describe components of different kits, not exclusive to this detail instruction manual.
Introduction to Fibergass
When considering the strength compared to the space age canopies that are common on most pod and boom helicopters there is no
contest. This plastic material is virtually indestructible at the penalty of being virtually un-paintable without specialized and
expensive automotive primers and paints, there is also a very limited range of color available. The reason you are reading this
page is that you have come to your senses and wanted to fly a model that looks and holds all the prestige of a real helicopter.
A wonderful attribute of fiberglass is in its flexibility. Century and Funkey take care and pride in craftsmanship that goes into
every fuselage. However, fiberglass parts will migrate (change shape) while inside the shipping box. When two mating components
are brought together and they do not align or mate, the culprit is a warped part. Many become upset and wish to lay blame but
dealing with this is very simple when explained a simple procedure. Using a heat gun set at the high setting at a distance of
1-2 feet away, evenly heat the warped part until the outside surface is hot to the touch and the part has become pliable
(flexible). Using adhesive tape, mate the two fiberglass parts together and let both parts sit until both parts have reached
room temperature. Remove the tape and now both parts are stable and match one another. In some instances, depending on the
location of the warp, the part may need to be held in an overextended position to achieve the proper shape when the part
Working with Fiberglass
Difficult to work with, we disagree. Fiberglass is easier to repair than you think. Using today’s CA type of adhesives,
a severe crack in a fuselage can be simply fixed and the repaired section is much stronger than in its original state. Add touchup
paint and no one would ever know it had been damaged. There is a limit to this type of thinking where purchasing the replacement
fiberglass part is simply cheaper and less work than performing major reconstructive surgery.
The Paint Job
There is no magic to a good paint job, the true secret is time, patience and common sense. A beginner who thinks that they
can throw paint onto a fuselage Friday night before flying on Sunday is dreaming, the helicopter would be flyable but even
that is a stretch. The average beginner will spend the better part of a month to apply a good clean paint job.
Preparing the Fuselage for Painting
After opening the kit version of the fuselage, examine all the fiberglass components to see where work needs to be done to
allow a simple "bring up" of the fuselage. "Bring up" describes the necessary steps to complete all the jobs in
order to start priming the fiberglass parts. Typical work that is done at this stage is rough sanding on seams and jointed
components, filling of surface imperfections, adding panel lines and rivets, cutting required holes and preparation for priming.
Start by thoroughly washing all fiberglass parts in mild detergent and warm water, this will remove anyresidue remaining from
the molding process. Next wipe down all the parts with Acetone (from the hardware store). The Acetone will remove all traces of
oil or grease that will affect the adhesion of two fiberglass parts or between the paint and the fiberglass. Now using fine
steel wool or an abrasive pad commonly used for scrubbing dishes, scuff all surfaces that will be joined or receiving paint.
What is important to note here is that we are breaking through the topmost resin surface and creating the best surface for
adhesive or primer to adhere to.
The prepared finish will have very fine score marks usually seen when the part is held to the light at a slight angle.
This is the time to rough sand any accessories or small parts, using the 320 grit sandpaper, that will be assembled and attached
at different positions on the fuselage. These can be marking lights, engine exhausts, scale fuel tanks, horizontal and vertical
stabilizers, guns, antenna or any scale details being bonded to the fuselage. These accessories should be test assembled to make
sure that all parts are prepared, and you will be able to see any problems that may arise in trying to paint these parts. Some
thought should be put into how to hold the part as it is being painted. Go ahead and bond these parts at this time using the
slow CA glue. A quick note on adhesives, as the fuselage resin is polyester, do not use any regular 5-30 minute epoxies to bond
two fiberglass components together. Stability is specially formulated for this purpose and excellent for fillets. Epoxy and
polyester will not bond properly to one another, but epoxy is good to bond unlike substances like wood or metal to themselves
or other parts.
Once the detail parts have been built into sub assemblies, they are ready to paint, use a filler in sections that have gaps or
slight surface imperfections, occasionally there are voids (air bubbles in the resin) that occur near the surface that need to
be filled. There are alot of good fiberglass fillers on the market, it is best to check with your local hobby shop to get a
recommended product. Try to stay away from porous fillers designed for wood as they will shrink and are not a good choice
for large areas.
Most major windows and accessory holes have been precut by Century, leaving only those that have a user dependency like the
type of exhaust system used on the helicopter or the exact exit position for the cooling fan shroud. For these fuselages
that have been explicitly designed for the Century’s scale mechanics, almost all of these concerns have been considered
and finished at the factory. This leaves the holefor the exhaust.
A. When making cutouts or holes in the surface of the fiberglass the best procedure is to drill a pilot hole using a 1/16"
drill bit at corners or along a curve. Start with a permanent marker to draw the opening or window. The pilot holes serve to
avoid leaving sharp corners which given the nature of a model helicopter will be the focal point for stress cracking originating
from corners. Once the holes have been made,
use the moto-tool for all other roughing cuts.
The cut off wheel is the best for straight
lines and either the sanding drum or the curved
stone is used for smoothing edges. If the
cut out is a window, do not use the moto-tool
for the final work. Switch to a sanding blocks,
square blocks of various sizes for straight
edges and round dowels for rounded corners.
B. In the case of the exhaust
opening, it should end up being 1/8"
larger across the outside diameter of the
exhaust pipe that extends below the bottom
of the fuselage. After drawing the circle,
use grinding stone and move in small circles
until the hole is at the size wanted.
Priming the fuselage accomplishes
two tasks: firstly, the primer paint is designed
to aggressively adhere to the surface being
painted and provide the best surface for the
colored paint to adhere to; secondly, all
surface imperfections will become visible.
Depending on the particular imperfection,
light sanding with number 600 or 800 sand
paper and the second priming will take care
of 90% of the highly visible problems. The
remaining 10% need to be filled, let dry,
sanded again and then sprayed with the second
coat of primer. The primer process will be
repeated until the surface is as perfect as
your patience and time permit.
Select your paint color
and follow the directions on the particular
brand of paint being used as each manufacturer
has different requirements.