From: Rob Lovell [bleu24ca@yahoo.ca]
Sent: Monday, March 25, 2002 6:19 PM
To: Bill
Subject: posible contribution for the web site
Having recently purchased a Shark and done some
limited restoration work I noted that the site lacks
an overview of the steps that should be taken to
completely redo a boat bottom. This is something I
did recently and while I am no expert I received allot
of advice from local folks who seem to have steered me
in the right direction.
The hardest part was putting all the require steps
(products) together... so this might help a new boat
owner like myself
So here we go:
Boat bottoms for Dummies:
Step 1- Strip Her Down (sounds more fun then it
actually is... trust me...)
The first step is to strip the bottom down, here you
have a variety of choices to do this (ie sanding,
light grinding, chemical stripper, scrapers, etc) It
is in my opinion very preferable depending on the
bottoms current condition to strip the boat down to
the gel-coat. Doing this reveals any blisters, cracks
and damage to the gel-coat that need repair. A couple
tips here:
1. wear a respirator (who knows whats on that bottom)
and its not worth messing your lungs up over a boat
bottom...
2. try not to dig into or deeply scratch the gel-coat
(this just makes for more work later)
3. don't be a moron and use automotive paint stripper
which will quickly eat Fiberglass and ruin your boat
(apparently a guy locally actually did that according
to the sales guy at Cross Canada (not the sharpest
tool in the shed).
Step 2- Repairing Blisters and Cracks in Gel-Coat
Ok this is not an area I am super familiar with so to
avoid giving bad advice I'll place a disclaimer and
say "consult an expert for additional information". I
personally used a grinding stone tip for my drill and
drilled out all the loose crappy material out of the
blisters until down to solid fiberglass below. Wipe
the area down with Lacquer Thinners to remove Mold
Release Wax from the area (Wipe it down 2-3 times)
Next its time to hit the Marine store for some West
System 2 part epoxy (No I didn't get a pay off from
West Systems for that ringing endorsement
unfortunately)...
There are several varieties of West Epoxy (ask the guy
behind the counter for advice cause I'll assure you he
knows more about that product then I do... failing
that West does place product information sheets at
every dealer ask your marine store for a copy...) Mix
a batch of this up and fill the blisters... then SAND
them smooth (once dry)
STEP-3 Application of a Barrier Coat
First, before putting a barrier coat on I would
suggest sanding to actual bottom of the boat to about
220- 350 grit (Tip most barrier coats dry with a rough
surface (a phenomenon called "orange peeling"... as it
looks much like the surface of an orange peel) and so
sanding to 600 grit or higher is a waste of time (in
my opinion)
Next Wipe the entire boat down with lacquer thinners
to remove mold release waxes that come off the
Gel-coat (again this was stressed to me as important
to ensure a good bond between the Gel-Coat and the
Barrier Coat)
The Barrier coat I used was Inter protect 2000 (again
a 2 part product)8
Next apply the barrier coat (can be rolled or sprayed
on) If sprayed this substance is very hazardous
I personally put 9 coats of Inter protect this thick
layering accomplishes two things:
1. It gives you a nice thick layer to sand
without risk of breaking through the barrier coat to
Gel-coat (which defeats the purpose of barrier coating
the boat in the first place)
2. Barrier Coat provides a protective layer
to keep water away from the gel-coat, which prevents
blisters etc.
Note the "window times" between coats without sanding
see the label on product for this...(this ensures a
good chemical bond between coats)
STEP-4 A Sanding Party
This is the step everyone loves start with 240-320
Grit (you are best to use a Dual Action Orbital Sander
to use this) I switched to a sanding block at 400 Grit
and began burnishing the boat (Burnishing is a process
by which you sand bow to stern only) I personally
sanded to 1200 Grit (which might be overkill but its
your time so...
A tip once you are using sanding blocks buy 3-4 and
bribe your crew to stop by using to enticement of
beer... when they arrive hand them a beer and mask and
a sanding block and assign a section of boat to
them... you will be done in no time flat and your crew
will love the involvement (whatever)
STEP -5 More Lacquer Thinners
Wipe the boat down again this will remove any mold
release wax as well any dust from your sanding party.
STEP -6 Anti Fouling Paint
Pick a product (I went with VC Offshore) and applied
it with a roller, once tacky, I then rubbed it down
with newspaper bow to stern again burnishing it (this
was on the advise of a Friend)
This will result is a good bottom for a boat that
stays in the water full time (you dry jailers would
probably go another way with things...
STEP -7 Go Rest for a while and get ready to sail
tomorrow
If you need instructions for this you are beyond the
scope of my ability to help.
Cheers
Rob Lovell
Shark #1766
Luff Diver
LaSalle Mariners Club