The Perfect Paint Job
December 2008
Our goal is to accomplish a paint job that with a strong foundation, with a maximum
gloss that will last for many years. This type of painting is not practical for the
everyday production body shop but will serve you well when you do a restoration or a
street rod job. We are going with the assumption that the metal, or fiberglass has been
stripped of all paint.
All bare metals and aluminum should have 80 grit DA scratches.
Bare metal is always best cleaned with #700-1 waterborne wax and grease remover then
let it sit 30-6o minutes before applying epoxy!
After first reading our Epoxy Tech Sheet, mix enough #6600 series epoxy to spray two
wet coats over the entire car. Spray one wet coat and let flash about 30 minutes, then
apply a second wet coat. Let the epoxy set overnight and then apply body, or fiberglass
filler and glazing putty over the epoxy. It is not necessary to sand the epoxy before
applying the fillers, as they will bite into the epoxy, and feather great. When you have
finished sanding all of the bodywork, you are likely to have some bare metal spots from
sanding. Spray one wet coat of epoxy over all filler spots and over any bare metal spots.
Let the vehicle set overnight.
The next day, you can start spraying the 2K primer over the epoxy. Once again, it is not
necessary to scuff or sand the epoxy before applying primer. The most important
thing to remember at this point, is spray one wet coat of primer, and let it set for 30
minutes before applying the second coat. Follow this procedure between coats of primer.
This step, when abused, messes up more paint finishes than anything else!
When all of the primer blocking and any necessary primer repairs have been done, it is
always best to use the epoxy as a sealer. Mix up enough epoxy to go around the car with
one wet coat, adding a double shot glass of SPI #885 urethane reducer, per quart. Let the
epoxy set for 30 minutes. Stir one more time, and strain. Spray one full wet coat of epoxy
over the entire car. The epoxy should set for 24 hours, then wet sand as needed, with
600-800 grit paper and then you are ready to base.
Next to rushing the 2K primer, rushing the basecoat is the second cause for the final gloss
and depth of a paint job to look bad. It is very important use the slowest urethane reducer
in your base that you can get away with, no matter what the outside temperature is. Just
allow enough extra time for the basecoat to flash and dry. The difference between a very
slow grade and medium grade reducer will show up in the final gloss. The slower grade
also has better solvency and will give you far better adhesion. Spray the first coat, and let
it totally dry, before spraying the second coat. It is best to wait 45 minutes between
coats.
Option if basecoat isn’t perfect:
After two coats, the vehicle should set overnight, then do minor wet sanding with 1500
grit sandpaper to remove any orange peel or trash. Apply the next two coats with 45
minutes of flash time in between. Some colors require additional coats. If this is the
case, again, wait 45 minutes between coats. Let the basecoat set overnight.
Tack off the next day, apply a wet coat of SPI-Universal, SPI-MS or SPI-HS Clear, and
let the clear flash as needed. Let the first coat of clear set 30 minutes.
Spray the second wet coat of clear, let it set 30 minutes, then spray the third coat of clear.
From two days to two weeks after the job has been completed, wet sand the clear with
400-800 grit sandpaper, blocking out any orange peel or dirt. After wet sanding, let the
car set in sun for a day then apply a wet coat of clear. Let the clear flash 30 minutes.
Apply a second coat of clear, then 30 minutes later come back with a third coat of clear.
Let the vehicle set two or three days in the sun to help to get all of the solvents out and
settle the paint job. If any wet sanding is required before buffing, sand with 1500 grit
sandpaper, then set the vehicle in sun for two to three hours. Bring the car back into the
shop, and allow it cool to room temperature, then buff.
If you follow these directions, you will have a durable paint job, with maximum depth
and gloss over a solid foundation, which will last for many years to come.
A friend of mine gave me this info 8 years ago and my shop has done it this way since with no problems..check out his website
www.southernpolyurethanes.com
