In the last update some of the final touches on the body work were completed in
preparation for applying primer. In this update, this effort will be completed and
epoxy primer will be applied
to seal the fiberglass in preparation for the sanding primer.
One of the first items to tackle was shaving the rear antenna. After giving it a
fair bit of thought I decided I'd prefer the clean lines of the rear deck
without the antenna in place.
So here's what I started with - the stock antenna mounted right above the rear
fender. I removed the antenna and got to work dishing out
the fiberglass in the area around the hole with a die grinder.
After the grinding was completed on the top side the surface was thoroughly cleaned prior to
application of the fiberglass and resin.
Once the top side was repaired the process was repeated on the underside to
create a full depth structural repair of the panel.
And here's how it ended up following the application of several layers of fiberglass,
sanding, and then filling the remaining imperfections with body filler. All told
this took about a weekend to complete (including down time waiting for the
resin and body filler to cure).
If you're interested in learning more about the process I
followed to shave the antenna check out the how-to video below, it includes a
lot more detail and information.
With the antenna hole taken care of the rear clip was ready
for primer. In the last few updates I took care of the body panel replacements
and miscellaneous body work to prep the panel for painting. I also block sanded
the entire rear clip with 180 grit sandpaper to blend in any deep scratches
created by the 80 grit sandpaper used during the rough body work.
Now that the sanding was complete I blew the body clean with compressed air,
gave it a quick once over with a water based wax and grease remover, and set to
work taping off the rear clip. I didn't want to get overspray anywhere so I was
careful to get the taping done neatly and cleanly with no holes or gaps.
I started by taping around the inside of the fenders with painters tape,
creating a margin about two inches wide.
With the tape in place pieces of painters paper were cut and then taped
into place. The painters paper works much better than newspaper because it's much
less prone to bleed-through. It can be bought at your local home improvement store
and comes in roles of various widths.
In the photo below you can see how the method I used provides good access for
painting the inner edges of the wheel well. Once the fender was completely
covered I taped the paper to the floor as a safeguard against overspray
And here's the rear clip fully taped off and ready for primer. I was certainly
looking forward to having it all one color again! I was also anxious to see how
my body work came out. I'll admit I was pretty nervous that the body seams,
especially those between the rear deck and the fenders, would be wavy.
With the entire car taped off it was given a thorough cleaning using a water
based wax and grease remover. Personally, I prefer water based cleaners since
they evaporate much more slowly and are easier to work with. To minimize the potential for fisheye I wiped
the entire car down three times with a thoroughly wetted paper towel, turning
the paper towel often and then replacing it once all sides were used. If this was
in preparation for base coat or clear coat I'd use a lint free
cloth. However, given that this is just for sealing primer, the thought
a stray lint fiber here or there wasn't a big concern for me.
For the purpose of this photo I wasn't wearing any gloves but, if you're doing the
entire car, the use of latex or nitrile gloves is necessary. Make sure you
Once the body was cleaned I started setting up to spray primer. Before I go any
further a brief explanation into my thought process is probably necessary. My
approach to painting the car will follow a multi-step approach. This first
application of epoxy primer is intended to seal the fiberglass. In many places I
sanded through the gel coat of the fiberglass panels exposing the individual
fiberglass fibers. The epoxy primer will seal those fibers and provide
a good base for the subsequent sanding primer, base coat and clear coat layers.
After a fair bit of research I decided to go with Southern Polyurethanes epoxy
primer. It comes highly recommended across many online automotive forums,
it's relatively easy to use, it's fairly forgiving to work with (you don't need
a $500 spray gun), and it's reasonably priced. The biggest challenge was
the required application temperature. The material I used needs to be used when
it's going to be at least 60 degrees during application, and for 24 hours after
The primer also comes in multiple colors. I chose white to match
the front clip (which won't be primed - it doesn't need it) and to provide a
contrasting color to spray the gray sanding primer over.
After carefully measuring out the base and activator the two parts were mixed
together and stirred very, very thoroughly.
Also, once the two parts are mixed you need to give the paint a chance to
catalyze before spraying it. This waiting period is called an induction period.
In the case of the Southern Polyurethanes primer the induction period was a minimum of 30
After the induction period was finished the primer was given one more good
stir, the paint gun was loaded and I put on my safety gear.
When using all epoxy
primers it's important to know that the use of personal protection equipment is
really important. Per the manufacturer's material safety data sheet (MSDS) they
recommend using a supplied air hood to avoid breathing in any fumes or harmful
chemicals such as isocynates. In my case I do very little spraying and, when I
do, all the windows and doors are open to provide good ventilation and I have a
fan running to increase air circulation. In light of this I opt to use a high
quality, tight fitting respirator with fresh filters.
I didn't remember to get any photos of the initial painting but here's how it
looked after getting two wet coats of primer onto the car.
The nice thing about the Southern Polyurethane epoxy primer is that it has a
semi-gloss finish that allows you to see imperfections in the paint pretty
easily. Despite my best efforts there were two small areas of fish eye. Once the
paint cured those areas were wiped down with cleaner, sanded and then wiped down
several more times.
In addition to the small areas of fish eye there were several spots where minor body imperfections
were visible. This really caught me by surprise because I could
have sworn I caught them all. Ultimately, I concluded it's just really hard to
see imperfections like this on a bare fiberglass panel.
Once I identified the surface imperfections I taped them off and applied a very
thin coat of body filler, sanded the filler down, removed the tape and then
block sanded the entire rear clip to accept a second coat of primer. The primer
worked very well for me but one down side is that you only have one week to
apply a second coat. Any longer and you have to scuff the surface before
painting over it. Since the content of this update was completed over the course
of several weekends I was stuck completing the extra sanding.
After lots of block sanding here's what the rear clip looked like. It seemed
like a lot more paint got sanded off than I expected but my primary goal has
always been to
have straight panels without surface imperfections.
It was eye opening to see how many spots I had missed in my first pass through
on the rear clip. It was definitely a lot easier to see the imperfections with
the primer on the car so I took the opportunity to dial in the body work as good
as I could before putting down the next coat of sealer/primer.
After sanding, cleaning and then cleaning again, I put down a final application
of epoxy primer. Similar to the first application two wet coats were applied.
And here it is, the primed rear clip ready for the application of high-build sanding primer. Overall, after
fixing all the little imperfections, I was really pleased with how it came out.
I gave the body a really good once over while the paint was still wet and glossy
and I was impressed with my rookie body work skills.
Here's a photo of the area I was most concerned with - the panel joint between
the rear deck and fender. I was real pleased with the fact that this seam came
out nice and even without a lot of "waviness". It just goes to show that using a
proper block sanding approach can lead to good results - even if your a
Well, that's it for this update. I'm going to continue the process of getting
the car to the point where I can ship it off to the body shop so stay tuned for
If you have any questions about this update, or a project youíre working on,
I encourage you to visit the Corvette Restoration Forum and ask
your question! Iím there fairly often and, together with the other great forum members, youíre sure to get some great
advice and feedback.