Painting my Ferrocement Hartley

[Grattaway]

Good morning

We own a 32ft Hartley ferro built 1974 by Sayer's boatyard in Whangarei
It is on the hard at Waiheke island for a hull repaint - first time out of the water for 4 years so lots of growth low down and not a lot of paint left below the waterline

I am sanding what little remains of the antifoul off which takes us back to bare concrete in places. In others there is still the original epoxy paint which is revealed once the antifoul is removed

My question - any advice as to what the first and/or second coats should be below the water line - I have searched the forums but didnt really find the answer

FWIW - I have seen lots of info regarding ferro boats - we love ours - its great to sail, robust and reliable, doesn't leak (and the keel wont fall off). cheap to buy for a great boat but difficult to insure so when I put it on the hard I insured myself - contractors all risks just in case of mishap

Any feedback appreciated
thanks and regards Wayne

[HankOnthewater]

I have follwed these steps on my Hartley boat and others as well:
1. important that the concrete has dried out
2. fill holes or/and fair where needed, use epoxy products, then sand+fair the fill-ins
3. epoxy prime first coat (I used mainly a Wattyl product)
4. follow supplier's instruction for second coat
4a....or while the 1st is not quite hard yet, apply coat #2
5. and you if think so, do the same with coat #3, but 2 coats should be enough
6. optional: at this stage some owners recommend a barrier-coat... but I never used one (and owner a ferro boat for 15 years and repaired/worked on at least 3 others)
7. and while the last epoxy coat is not quite hard yet, roll on first coat of antifoul
8. now you have a few weeks to apply the second coat of antifoul

Paint has never fallen off, from a boat I prepared and painted, never had to redo a job..... sofar

[Grattaway]

thanks Hank OTW

did the wattyl product that you have used have a name

and does it work ok over existing epoxy and/or antifoul. I have sanded and then resanded lots but still a few areas of existing epoxy which appear sound enough to leave but also very small spots of antifoul in places which may be more of an issue. Hull has clearly been antifouled straight onto the ferro in places in the past


Rgds Wayne

[GordMay]

➥ http://www.wattylpc.com/documents/pc...Guide%20v7.pdf

[HankOnthewater]

Hi Grattaway
Check the link Gord provided (thank you Gord). You can see what Wattyl suggest ie on page #16.
I can not recall the exact product name or numbers I used, but maybe able to check, if I have still the records. I still use the Wattyl Seapro epoxy fairing on steel, GRP and timber, both above and below the waterline. And after 20 years of using this, never had a problem with it.
BTW, as you can see Wattyl suggest to use a tiecoat (what I called a barriercoat). Indeed most yards suggest that as well (and not only with Wattyl products), but as I said, I hardly ever use it, and have never on my boats. Yes, not using it, is riskier for us as an owner/painter and using it, guarantees the yard or supplier with another sale of 5 to 10 litres...... I guess they want to minimise a risk of failing paints. For them to apply such tiecoat is a win-win situation.

[stnick]

Can you use swimming pool paint ?

[Grattaway]

Good morning

thanks guys for info and feedback - much appreciated

One question - I have talked to the Wattyl guys and they recommend Seapro TC90 as the first couple of coats below the water line. It is a single pack chlorinated rubber coating but most people including you guys recommend or use an epoxy under the antifoul

Does Wattyl's choice sound Ok - its certainly easy to do and quite tolerant of low temperature when applying

Regards Wayne