|
The repairs done to the plastic (or any
other type of material) is often very painstaking. To properly repair
a fracture or crack in a plastic case takes a number of steps. 1st the
crack or fracture must be cleaned to remove all foreign material
(grease, dirt and other contaminants). Then the proper adhesive,
usually a cyanocrylate or epoxy (depending on the type of plastic)
must be chosen and worked into the crack or fracture. If epoxy is
used, the size of the area to be repaired determines the type. For
small areas, I'll use the quick setting steel filled epoxy like JB
Weld, the slower setting stuff for larger areas. I then clamp in
place until cured.
If a chunk or piece is missing, I fill with a
high quality liquid epoxy (I recommend Tap Plastic's Super Hard 4-1).
Often a mold or dam is needed for this type of repair. After curing is complete I
sand and then "micro-sand" to smooth
it out and make the repair as invisible as possible (micro-sanding
consists of using a series of flexible sanding cloths from 1500 to
8000 grit). Depending on the staining at the fracture depends on
whether the repair will be invisible or not. Prior to applying the
adhesive I also attempt to "bleach out" any stains. This is not always
possible as some plastics absorb contaminants.
After all the sanding
is done the finishing touch is a good rubbing with a polish such
as blue magic.
This makes a nice solid, smooth repair even if the fracture or crack
is still visible.
If needed, a nice paint job from a spray can is possible.
If
done right it can look very professional. The first step after the
repair is done is to give a good primer coat or two then sand with lightly
(or rub "0000" steel wool).
Most flaws in the repair will now show and should be corrected and
another primer coat applied. Once the job looks good with the primer
paint, smooth out with "0000" steel wool, blow away the dust and
give the first application of a couple of light coats of paint.
For a professional looking paint job, it
takes more than one or two coats of paint from a spray can. After the
first coat is dry, rub lightly with "0000"
steel wool, clean away dust and apply the second coat.
The secrets to a professional looking paint job are:
-
(1) Use only the best quality paint, I use
and recommend Krylon for color applications and Mohawk for lacquers
and toning.
-
(2) The right temperature, if too hot or two cold
the result will be a poor job. Follow the instructions on the paint
can.
-
(3) If the paint is applied too heavy or two light, this
is not good, too heavy will result in runs, too light a speckled
or gritty look. To avoid the just sprayed finish look, maintain a
wet surface without runs. Don't give it a light spray after it
has just started to dry, this will result in a sandpaper surface, the
gritty/rough look you see so often with spray-can paint jobs.
-
(4) Lightly rub with "0000" steel wool between
each application of the paint of several light coats while maintaining
the wet look. For a nice looking job, 3 - 4
applications of 1 -2 light coats are necessary for a professional
look. When the last coat has been applied, let it cure for several
days in a hot attic or bake or if you know how, you can cure the pint
by baking (Bakelite only, other type plastics may melt) in an oven.
You find out what the right time and temperature is, I prefer the hot
attic.
-
(5) After the paint has totally cured, you
can now give it's final rubbing with "0000" steel wool. Be careful not
to overdo the rub. You just want to rub out any specs, or loose pint
that was not totally fused to the main body of paint. After the steel
wool rub, finish with with a blue magic
rub for a fine, smooth professional looking finish.
The above processes are very time consuming and
often is not worth the time it takes. I would not consider doing it
for anyone but myself. My practice is to do the best I can when I
restore something whether I intend to keep it or not.
click
here for an example of one of my
repairs
click
here for more info on restorations
click
here for
my "Tech-Tips"
(tips on electronic and other restoration practices I have learned
over the years and will share) |