Bottom Paint

VisionIsle

Petty Officer 3rd Class
Joined
Feb 10, 2006
Messages
98
Can anyone tell me how much time is needed to prep and bottom paint a 25 foot fiberglass boat bottom. How many gallons will I need and is it worth doing yourself?

How about painting an outdrive as well?
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,123
Re: Bottom Paint

VisionIsle, If the boat has been painted before, you will simply roll on another coat. If it has not been painted before, you will want to use some primer. If the boat has never been kept in the water, and you are afraid it will develop blisters on it's bottom, you will want to use an epoxy barrier coat. I used some Pettit epoxy barrier coat on my 19' footer, and it worked very well. The epoxy has a recoat specification, based upon the temp. Since I did the work in early spring, the recoat time was 24 hours. I would mix up a quart of the barrier paint and roll a coat on the bottom each morning before work. On the fourth day, I rolled on the first coat of ablative bottom paint. The next day, I rolled on the second coat. That was it. 3 coats epoxy, 2 bottom paint. My 19' footer used a gal of epoxy barrier paint, and 1 gal of bottom paint. I would figure your 25 footer would need at least two gal of each. After the first coat you will know if that is true. Use masking tape along the waterline to get a straight paint edge.

Should you do it yourself? If the boat is up on blocks, it will be easy to paint the waterline with a brush and roll the remainder. Use outdrive antifouling paint on the outdrive. There is special stuff made for it. Reqular bottom paint will corrode it severly.
 

stevieray

Lieutenant Junior Grade
Joined
Jul 18, 2006
Messages
1,135
Re: Bottom Paint

I put a blurb on the outdrive paint over on your other thread. Good advice above from Chris on the bottom. I have a 1988 23 ft Celebrity & since it is so old I skipped the barrier coat & just sanded the bare bottom. Took me just 2 qts of Interlux ablative to do 2 solid coats.
 
D

DJ

Guest
Re: Bottom Paint

Excellent advice from Chris.

DO NOT paint the outdrive with the boat bottom paint.

Your number one priority, for the outdrive, is making sure your zincs (clean aluminum looking blocks) are clean and NOT painted.

As mentioned, there is special outdrive ablative paint.
 

VisionIsle

Petty Officer 3rd Class
Joined
Feb 10, 2006
Messages
98
Re: Bottom Paint

Thanks for the advice, I should have mentioned that the boat is kept in water at the San Leandro Marina. It was painted 2 years ago and is scraped by my diver every 3 to 4 months. The last time he said it was blistering and it was time for bottom paint. When they haul the boat out the will pressure wash it for me. Is the best way at this point to begin by scraping the rest of the algae off, sand and then apply ablative bottom paint? I was thinking of two to three coats of the stuff and hoping to get 3 years in the water?

Carden
 

stevieray

Lieutenant Junior Grade
Joined
Jul 18, 2006
Messages
1,135
Re: Bottom Paint

Sounds like a plan. 3 years may be pushing it - depends on how much you run it (ablative wears off as water moves over the hull - kind of like a bar of soap). I'd expect 2 seasons - but I pull mine out from Nov - Apr so it only sees air during that time.When sanding - wear a real good respirator & cover up as well as you can. First boat I did I used those cheap dust masks & spent a week in bed nearly paralyzed - bad stuff in that bottom paint.
 

stevieray

Lieutenant Junior Grade
Joined
Jul 18, 2006
Messages
1,135
Re: Bottom Paint

Also, make sure that your new paint is compatible with what's already on there - some will not stick to others.
 

VisionIsle

Petty Officer 3rd Class
Joined
Feb 10, 2006
Messages
98
Re: Bottom Paint

Thanks! I sure dont want to be breathing that stuff, the last paint was Pettit Trinidad S/R. Ill stick with the same brands. Any advice on painting an outdrive?
 

stevieray

Lieutenant Junior Grade
Joined
Jul 18, 2006
Messages
1,135
Re: Bottom Paint

VI - Trinidad SR is a hard paint - not an ablative type. You should be able to overcoat with an ablative like Ultima SR - I see nothing in the literature that says not to.
 

swist

Senior Chief Petty Officer
Joined
Jul 1, 2004
Messages
678
Re: Bottom Paint

I'll throw a contrarian view in here. Bottom painting is, like all upside-down painting, not easy to do neatly, and the trailer doesn't help if that's involved.

Also the paints themselves and their primers/cleaners are extremely toxic. I am a fanatic do-it-myselfer on just about everything on my boat, but I draw the line at bottom painting. Let someone else do it.

Just my opinion.
 
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