Bottom Painting Fibreglass boat first time

I would suggest skipping bottom painting all together. Total pain that once on, you’re committed to pretty much forever. I don’t see the point don’t seem to stop growth.
 
Are you kidding?
Nope. Pretty sure all the harsh stuff in the paint that used to stop growth has been banned. Better to just haul out a couple times and clean the growth off, as opposed to hauling out cleaning the growth off and maintaining and touching up the bottom paint
 
Nope. Pretty sure all the harsh stuff in the paint that used to stop growth has been banned. Better to just haul out a couple times and clean the growth off, as opposed to hauling out cleaning the growth off and maintaining and touching up the bottom paint
Huh.. I've been told by people who use ablative paint that it's essentially bare after 4 months in the water
 
I’m no pro, I moored my boat for over 15 years at burrard civic in false creek which gets heavy growth, bottom paint didn’t seem that great to me. I’d watch the guys with no paint hulls pressure wash off and be done. Meanwhile I’m pressure washing the same and then buying expensive paints and going through that whole process, mind you just touch ups but still extra work and effort
 
I prepped the bottom, put on two coats of interprotect barrier coat followed by two coats of bottom paint. It worked out great, but was brutal and I wouldn’t do it again. But once the bottom paint is on, touch up and subsequent coats are easy, and I do that myself. The first coat, and preparation required is what I wouldn’t ever do again.

Bottom paint is essential if you moor your boat, which I do. It works very well and keeps the growth off.
 
interprotect provides a chemical bond being epoxy based but with a well cured older gelcoat there is no harm in adding some mechanical bond by sanding, a light soda blast would be even better but overkill in most cases.

Dmurph- do you know what paint was used on your hull, they’re definitely not all equal. micron csc is what have experience with and growth is essentially non existent. I wonder if you had something else that doesn’t perform the same.
 
Last edited:
Wrong! Do NOT use CSC on aluminum. It carries 40% copper. Why use a MSDS sheet?

For aluminum, use ONLY Micron CF.

Micron CSC suitable substrates are:
GRP / FRP
Lead
Steel
Wood
Bronze / Stainless Steel

"-ca"....is the new junk for "canada": it would be pretty bad for the manufacturer to publish a false msds:

Substrates
Aluminium / Zinc-Galvanised Steel
GRP / FRP
Steel
Wood
 

"-ca"....is the new junk for "canada": it would be pretty bad for the manufacturer to publish a false msds:

Substrates
Aluminium / Zinc-Galvanised Steel
GRP / FRP
Steel
Wood
Micron CSC is available here. The biocide is copper. I just purchased 2 gallons, locally.

CSC-CA also indicates that it is NOT to be used on sterndrives.

MSDS sheets are for first aid. For manufacturer's recommendations, please read the Technical Data Information.
 
interprotect provides a chemical bond being epoxy based but with a well cured older gelcoat there is no harm in adding some mechanical bond by sanding, a light soda blast would be even better but overkill in most cases.

Dmurph- do you know what paint was used on your hull, they’re definitely not all equal. micron csc is what have experience with and growth is essentially non existent. I wonder if you had something else that doesn’t perform the same.
Sometimes people blame a product when it's operator error:

"This innovative copper-copolymer formula of Micron CSC provides a controlled release of antifouling biocide at the paint surface, which means that the longevity of the coating is related to the amount of paint applied. Micron CSC will not lose its effectiveness when hauled out of the water for extended periods of time (such as winter storage).* All that is needed to reactivate the paint in the spring is to wash the surface using a stiff brush or lightly power wash.*"
 
Nope. Pretty sure all the harsh stuff in the paint that used to stop growth has been banned. Better to just haul out a couple times and clean the growth off, as opposed to hauling out cleaning the growth off and maintaining and touching up the bottom paint
The biocide in CSC is copper. That, in sheets, was used on the old sailing ships for centuries.
 
HMS Victory, Commanded by Lord Nelson, which fought and won Trafalgar had just been copper sheeted not long before its battle there on Oct 21/1815, specifically to reduce marine growth in order to maintain its incredible high speed of 10 knots. Super high tech. Then.
 
HMS Victory, Commanded by Lord Nelson, which fought and won Trafalgar had just been copper sheeted not long before its battle there on Oct 21/1815, specifically to reduce marine growth in order to maintain its incredible high speed of 10 knots. Super high tech. Then.
Same treatment for the 20 knot Tea Clippers of the 1800's.

The White Cloud was built in the McKay Shipyard, in Boston. Donald McKay was born in Nova Scotia and had a brilliant career as an architect and builder of clipper ships. The White Cloud made the trip from New York to San Francisco in a record 88 days. That meant rounding Cape Horn. The skipper was also a Nova Scotian. The previous record was 200 days!
 
Wrong! Do NOT use CSC on aluminum. It carries 40% copper. Why use a MSDS sheet?

For aluminum, use ONLY Micron CF.

Micron CSC suitable substrates are:
GRP / FRP
Lead
Steel
Wood
Bronze / Stainless Steel
Interlux is no longer selling Micron in Canada. They have put up a procedure for using their other products on alu. It requires something like 5 coats of interprotect before adding the other products. If you know of any micron lying around you can probably sell it for a pretty penny.
 
Interlux is no longer selling Micron in Canada. They have put up a procedure for using their other products on alu. It requires something like 5 coats of interprotect before adding the other products. If you know of any micron lying around you can probably sell it for a pretty penny.
NeverMind! I mixed up the micron with Trilux, whoops
 
Awesome, dude! We all make mistakes. A rare man admits to them. ;)
Thanks! I make them often enough I would be a fool to not admit them.

The reason I was looking into bottom paint for metals was to paint my outboard bracket along with the portion of skeg that does not trim out of the water. I think the micron is not suitable for outboard alloy. I was going to use Panaten as the boat is only in the water for 6 months or so. I have searched the forum a ton and I see mixed reviews with panaten. I did find a product called Desitin maximum strength which has a higher zinc content than panaten (40% vs 13%). I will report how it works at the end of the season.
 
Thanks! I make them often enough I would be a fool to not admit them.

The reason I was looking into bottom paint for metals was to paint my outboard bracket along with the portion of skeg that does not trim out of the water. I think the micron is not suitable for outboard alloy. I was going to use Panaten as the boat is only in the water for 6 months or so. I have searched the forum a ton and I see mixed reviews with panaten. I did find a product called Desitin maximum strength which has a higher zinc content than panaten (40% vs 13%). I will report how it works at the end of the season.
You will not be disappointed. I couldn't immediately find Penanten so bought Desitin. You nailed it- it's the zinc content. Plus, it leaves you with wife-friendly hands. It has worked well for 2 seasons now. I smear it on the drive fairly generously. No, it's not a pretty sight but that's why you're checking out your wife, instead.
 
Back
Top