Antifoul, primer and gell coat in patch mode.

[pcatterall]

About to start on the antifoul soon. I usually just scrape of the loose bits, key the good stuff and slap another coat on top.
I notice that sraping off some loose bits takes me back down to the gell coat.
Do I have to prime all these small patches?
If my primer goes onto the surounding old antifoul ( as it will!!) will it adhere ok?
Regards Peter

 

[Airassmith]

I've got a similar problem and intend to use a primer coat of Hempel (Blakes) Underwater Primer or International Primocon before the antifouling, which seem to be recommended for this sort of situation. In my case there is an epoxy coat underneath the antifoul but whilst sanding I've managed to go through it in a few spots. I'm trusting that the primer coat will cover all before the new antifoul, although I'm a bit unsure how the primer will stick to the old epoxy.
Dave

 

[oldsaltoz]

You may have to apply a little epoxy primer, use the high build type.

Andavagoodweekend......

 

[hurley]

This happend to me last year. As an experiment I just removed all the loose stuff, then painted over it all (patches down to the gel coat included). I only put a thin coat of eroding antifoul over it all, with two coats on the leading edges and waterline.

Then when lifted out after 6/12 the yard presure washed the boat down. The result after all this was more or less where I was last year, and so I will just do the same again.

The boat was not excesively fouled. My experiment is based on previous threads in this forum where members have stated that you can try an approach of just putting enough antifoul on that will erode off by the end of the year, thus reducing waste and saving time on preparation and money.

In my case I have a half tide mooring and my boat a twin keeler stands up nice and high on very hard mud. I also only keep the boat on a mooring for 6/12. The water is flowing arond the boat as it is in a tidal river.

I would stress however that this is only my "experimental" approach. So far it has worked well for me. The other thing I think about is at least I am not scratching the gel coat with a steel scraper every year and thus degrading its ability to minimise the process of water ingress via the process of osmosis.

Also I dont spend loads of time preparing and giving loads of money away to the paint industry, not to mention the environmental implications.

Please don accept this post as an expert opinion its just the way I do it which seems to work for me. I am only a relative novice.

I wonder if anyone else does it this way ?

 

[pcatterall]

Thanks all, I have been doing as per Nicks method for a few seasons without problems. This year I was being a bit more aggresive with the flacky bits and thought I should maybee check in with experts. part of my hull has been epoxied ( my experiment and that definately sheds the antifoul so defo primer on that area but the antifoul seems to stay ok on the gell coat.