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  Topic Review (Newest First)
07-15-2012 07:33 AM
Re: Bottom paint over Gel Coat without Barrier Coat?

You do NOT move things around with 4 stands as your supposed to have six and REALLY need seven
07-15-2012 12:58 AM
Re: Bottom paint over Gel Coat without Barrier Coat?

Ok newbie question coming...
with boat on the hard how does one apply the bottom coat, where the 4 jackstands that hold up my boat, touch the hull?

Boat currently has a fairly decent looking BOTTOMKOTE RED XXX, INTERLUX so I was just planning on adding another coat before fall in prep for launch next spring.

Will add some pictures later Sunday when I return from the boatyard where she sits.
04-25-2008 03:56 PM
WagTheDog Thankls for all the comments/suggestions. I guess I'll be doing the following:
- Sand down existing bottom cote to smooth edges where bottom coat/anti foul has been scraped down to the gel coat.
- Apply 2x layers of barrier coat to exposed gel coat.
- Apply 2x layers of bottom cao (anti foul) to the entire hull.

This should afford the hull sufficient protection of the season. Then in the fall...SOAD BLAST! Gotta save some money though!

04-24-2008 07:54 PM
craigtoo Howdy..

Here's a thread... but maybe it'll be important for you next year...

I just want to emphasize one thing. I think it's important to not apply barrier coat to bottom paint...I also know how hard it is to completely get bottom paint off... I'm not a bottom expert. Search this forum.. you will find good info...

For the record... I was looking for 10 years of protection.

I went for 14 coats of epoxy...(2 then 12 Interprotect)
3 coats of bottom paint (1 hard 2 soft... Petit)

04-24-2008 05:57 PM
JimsCAL It sounds like the 1/3 that you scraped is ready for new barrier coat. I would apply barrier coat there and tackle the rest next winter.
04-24-2008 03:53 PM
WagTheDog Barry,

Nice write up! I'm in exactly the same position money wise. Hopefully I'll be able to scrape together $1,000 to have the boat soda blasted in the fall. A couple of coats of antifoul it is then. I just wanted to make sure that a season without barrier coat in some places would not cause blistering.


04-24-2008 03:38 PM


IMHO, if you want to sail now, just apply antifouling paint and then splash the boat. If you want to apply a barrier coat next year, you will have to strip off all the paint (new and old) before you do.

I went through the paint strip, fair, barrier coat, bottom paint process this past winter. I did a write up on it, which you can read about here:

Good luck,
04-24-2008 02:20 PM
WagTheDog Sailermon: I only managed to scrape off the anti foul and barrier coat on roughly 1/3 of the hull before I quit. I still have anti foul (over barrier coat) left on the rest of the hull. If I want to sail this spring I have two choices: (1) Sail with the hull as is which means that roughly 1/3 of it (spread around the hull at various places where I scraped off the old anti foul that was cracking badly) would be gel coat exposed to sea water; or (2) Sand down the rough edges where the anti foul/barrier coat was scraped off and where the gel coat has been exposed and put a couple of coats of barrier coat over the entire bottom of the hull. I'll strip the hull to the gel coat in the fall. I'm just not sure which choise is the better one.
04-24-2008 11:15 AM
Sailormon6 Maybe I'm mistaken, but I thought you said you either scraped or sanded off all the antifouling, and that the only thing remaining is some of the barrier coat, which you are going to sand smooth at the edges. If so, I think you can apply barrier coat over it all, and then apply your antifouling. If all the antifouling is gone, you don't need to do any sand or soda blasting.

On a previous boat, I removed all antifouling from the keel, and left some of the old barrier coat, and added new barrier coat over the old, and it worked fine.
04-24-2008 10:55 AM
T37Chef Soda blasting is the preferred method these days, easier on the gel coat. I think waiting till the fall will do little or no harm to your boat, especially if you see little or no signs of blistering.

Yes, you must remove all the old bottom paints before applying a barrier coat. After having mine blasted I sanded it done smooth and removed any remaining bits of old paint.
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