article covers the preparation and painting of ABS shells.
Smoothly does it
I'll start by saying straight away that
the quality of the finish you achieve depends on the
quality of the preparation, the more time you take to
get the foundation right and the more time you take
to complete each step carefully and slowly the better
your end result will be.
As I rule I always say that if you can
feel it, you will see it. What I mean by this is that
if you run your fingers along the surface to be painted
and can feel any imperfections then it *will* show through
the paint generally. Take your time to remove all paint
that you can and smooth any imperfections out of the
plastic using a fine grade wet and dry paper. I normally
use 1500 grit for this in warm water containing washing
up detergent. This should give a smooth and flat finish
but look very closely and you'll see millions of tiny
scratches, perfect for the paint/primer to grip onto.
Be careful not to sand too aggressively though on your
bare plastic as you could lose some of the critical
body detailing. The main thing is to remove old paint
and the smaller scratches.
If your shell needs repairing this is
the time to do it before any primer goes on, deeper
scratches can be filled using automotive body filler
and smoothed, again smooth this down until you can't
feel any imperfections.
If you're painting a new shell then the
above still applies, I always wet sand new shells in
the same warm soapy water to create those vital minute
scratches giving the primer a surface it can "key"
to. Once you've finished rinse the shell in clean water
and leave to dry. Be careful at this time if you use
a cloth or paper to dry the shell as you may be leaving
particles of dust of paper etc behind, best to let the
shell dry of it's own accord if you can. The shell should
look like it has a matt finish, perfect!
It's prime time!!
As Tamiya don't sell an acrylic primer
in the UK I actually use an automotive plastic primer
or Tamiya Acrylic matt white. Add the primer in thin
even coats. Here are my top tips for using spray can
- Warm the can in hot water for about
1 minute before use. (This helps the paint to mix
and increases the internal pressure inside the can
which gives a more consistent and finer spray)
- Spray in a ventilated but warm space.
A garage is perfect. Summer months are best of course
but you can warm the air first using an electric heater
to increase the temperature and lower the moisture
in the air.
- Hang the shell or mount it on a post
high up give you good access from all angles and away
from the potential dust that may be kicked up from
a work surface.
- Spray even thin coats of the spray
from a distance of about 8 inches. Sweeping the can
past the shell and pressing the nozzle down only as
you pass is the best technique.
- Don't be tempted to put too much on,
you just need coverage, runs are a nightmare to deal
with but you can always add more coats of paint.
The above techniques obviously apply to
the primer stage. Once the primer is dry check for any
scratches still showing through and if necessary wet
sand again and apply more primer. Do this until you
are happy that you have a blemish free and smooth foundation
for the top coat of paint. If you want you can wet sand
the primer just to get a smoother finish before applying
the paint. Wet sanding rather than dry sanding is always
best as the water helps remove the paint from the paper
which stops it clogging and makes it more effective.
As a safety issue it also eliminates dust that is best
not to breathe in.
Time for top coat
I have used various types of paints on
my shells in the past but have found Tamiya Acrylic
paints to be the best bar none. Automotive spray can
paints can give good results but due to them having
a larger nozzle hole they generally tend to give a rougher
finish, of course it's still possible to flatten this
down and achieve a great result but it's harder work.
I do actually use automotive paints on my runners where
a thick durable finish is the main priority rather than
a super deep and flat finish but more on the finishing
Next up is your top coat paints. If you
plan to use more than 1 colour as a rule it's best to
spray the lighter colours first as the darker colours
will show through lighter ones and take many more coats
to cover. Spray your paints in light even coats and
leave to dry for at least 2 hours between coats. If
you can a longer rest is advised and if necessary you
can wet sand each coat as above to get a smooth finish.
I only really think this is necessary on the final top
coat before lacquer but it's up to you. Once all top
coat colours are on leave the shell to cure for at least
24 hours before you do anything. It's an agonising wait
but trust me it's worth it! As I have just mentioned
it's a good idea to wet sand the final layer down, this
gives a lovely flat surface for your lacquer.
Not everyone uses lacquer but there are
really many benefits to it as follows:
- It seals in the paint to give a protective
- It will give the paint a better shine
and visually more depth
- It can help prevent UV paint pigment
- It can be flattened and polished to
a mirror finish without wearing down top coats of
The main point for me is the last one,
as a rule I will apply 3 coats of lacquer and then leave
overnight before polishing to a mirror using automotive
polish and elbow grease. You really can repeat the polishing
time and time again until you get a truly glass finish.
Remember though, you are removing the lacquer as you
do this so keep an eye on your polishing cloth for colour,
if you see any then you've gone through the lacquer,
don't worry though you can always wet sand and apply
more if you need to. You can accelerate this process
by wet sanding the lacquer using very fine grade paper
(1500 grit or finer) before polishing but be careful,
it won't take much to remove the lacquer!
Some modellers prefer to apply decals
before the lacquer process above but I personally don't.
It's a subjective thing but here are my reasons for
not doing it:
- Fear of a reaction between the lacquer
and the decals
- Fear of an edge of decal not being
- No chance to remove the decals and
move then etc.
- Easy to polish through the lacquer
at the edges of decals where it's raised
- 1:1 vehicles would have sponsor decals
applied over the top of paint as vinyls generally.
Up to you of course but whatever you do
I hope this article has helped to give some pointers
for perfecting your technique.