Antifouling a hull for the first time.

I havent had chance to look at options yet but boat has No antifoul currently and is to be kept in the water in Solent area.
 
If new and made of polyester, start with a proper set of epoxy coats. This will last a long time and protect the hull. I'd go for 4 or 5 coats at least.
Most epoxy vendors have a system for applying with specific timing between the coats and also for the first A/F coat.
 
Use Coppercoat. Ours is 4 years old and still going strong. Why put paint on every year. With it being epoxy based it also helps protect the glass fibre and gel coat. Its possible to DIY.
 
z1ppy said:
what hull prep is required to antifoul a hull for the first time???

scoring the grp ??

undercoat / primer??

thanks
Click to expand...

Depending on the intended use, a basic surface preparation from new normally consist of a degrease followed by taping the waterline then abrasion of the hull surface followed by application of a primer in two coats and then followed by the antifouling also in two coats. If an epoxy coating such as Gelshield is to be used alternate coats of green/grey are used numbering normally 5 coats followed by the antifouling. Different manufacturers will have slightly different coating systems, the above applied to International products.
 
Antifouling

As Minkysailing says you must start the job by degreasing the hull. If you don't do this part properly it doesn't matter what products you use as they will probably fall off. If it's a new hull out of a mould, even if it's been sitting for a while during fit out, it will have a mould release agent on it, a hard wax that will be quite difficult to remove. For most release agents the best process is scrubbing with detergent, hot water and a Scotchbrite pad. You can check if the wax is removed when you rinse the surface - if the water spreads in a thin film it's OK, water beads up then do it all again.
It is important to degrease before you abrade the surface
 
Have to say all above posts look like good advice.

The only item not mentioned that I have done for many years is to apply a thin skim coat of the primer just before applying the first coat of antifoul.

This has two purposes.

1- The antifoul and skim coat (not fully cured) mix and form a good bond to the hull.

2- When scraping back in the future you will the mixed area before you cut into the original primer.

Good luck and fair winds.
 
Just to add a little more,

the boat is not new. for the first year of its life it was not antifouled. it was antifouled in second year of its life and in the 4th year, the antifoul was removed.

From the look of the hull it was done with chemical / scraper as the finish is extremely good and if the vendor hadnt told me about the history, i would have assumed it had never been antifouled.

we are now into the 6th year of its life and i am looking to keep her in the water hence looking at antifoul options...
 
I'd second, or third, the suggestion that this is a perfect opportunity to apply Coppercoat. Most of us had to get layers of old crud off first! I found that slurry blasting was extremely effective for this, although slow, as the British weather kept getting the sand damp and it stuck in the tubes. A valuable side effect is that the operator gets a nice tingling exfoliation of the face whilst working - cheeks as soft as a baby's bottom. The finish is a very good key for any subsequent application, lightly pitted like an eggshell.

Rob.
 
z1ppy said:
what hull prep is required to antifoul a hull for the first time???

scoring the grp ??

undercoat / primer??

thanks
Click to expand...

Given that the preparation with expoxy is equivalent to the effort to paint coppercoat, and you start with an already clean hull, just go with COPPERCOAT. That is what I would do if I had not already an hull with antifoul.
 
Having applied copper coat two years ago, including needing to have the hull blasted first, i would definitely agree that the vast majority of the effort and also cosst is involved in surface prep, the actual coating only took a single day. As such I would not hesitate to copper coat in your situation, although i would also strongly consider applying a number of coats of an epoxy barrier before hand. Although copper coat is an epoxy, it is water permeable - it needs to be in order to allow the copper to be oxidised - and so whilst it may give some protection against osmosis this is nothing like as much as a dedicated barrier layer.

If you're interested to see the effects of copper coat I posted some photos here a few months ago of my boat when she was first lifted, after 2 years in the water and mostly static innn a Marina.
 
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