Antifouling Options

Tips and pointers to keep the critters away
martica
Posts: 117
Joined: Sat Jan 09, 2010 2:19 am
Location: brisbane

Re: Antifouling Options

Post by martica » Tue Dec 03, 2013 10:37 pm

Hi Paul a friend of mine as looked into this it's not a cheap product but if works like in the video it would have many applications if you like give me a call I can put you contact with him cheers mick

mahnamahna
Posts: 579
Joined: Wed Aug 02, 2006 4:48 pm
Location: Gosford NSW

Re: Antifouling Options

Post by mahnamahna » Wed Dec 04, 2013 9:46 am

Thanks Mick, Perhaps you could ask your friend about the stuff and let us know. Or maybe I could buy a small amount and test a panel of it to see what it did. Problem is I no longer have access to a non public wharf. If I hang a test plate a place in public it may not stay there long.

I figured the stuff would be expensive, the pure seal was too but it promised savings in the long term because you only applied it once in about 5 years and when compared to haul out and re application costs of normal antifoul you came out in front.

I have copper coated hulls and this is a bit hit and miss from reports I have, it seems to work well for some and not at all for others and I cant seem to nail down why.

The 2 most obvious applications I am interested in are as an antifoul and as a rust inhibitor.

As an antifoul just because it beads water does not mean organisms cant still adhere themselves and grow on it. I would be interested to know if anyone has tried this. And what are its abrasion resistance. For example how long will it stay effective on a surface that has constant water movement across it. If it wears off fast it would not be a very effective alternative antifoul.

As a rust inhibitor if water is completely repelled from the surface of anything coated with it does that mean that it cannot then oxidise and start the rust process or are tiny traces of water on a molecular level left that still cause rust.

44c
Posts: 1146
Joined: Tue Aug 08, 2006 5:08 am
Location: Hervey Bay, Qld

Re: Antifouling Options

Post by 44c » Thu Dec 05, 2013 6:19 pm

For most boats 5 years between haulouts isn't an option anyway. Saildrives need their anodes replacing etc etc.

groper
Posts: 239
Joined: Sun Nov 18, 2012 11:23 am
Location: cairns

Re: Antifouling Options

Post by groper » Sun Jun 22, 2014 2:40 pm

Mahnamahna, as the copper coat being hit and miss, I think I've worked out why. When I built a replacement rudder for the oram we recently purchased, around 18 months ago now I think, I copper coated the rudder so it matched the rest of the boat. When copper is applied in epoxy, the epoxy seals off the surface as the resultant blend is mostly non porous . The mixture doesn't ablate so once the copper on the surface is gone, no more copper is exposed and barnacles start to grow.

When I built the rudder, I sanded the copper coat lightly to expose fresh copper in the matrix before giving it another coat - it went from a dull brown colour pre sanded, to a golden sparkly colour after sanding. I thought to myself, it's going to work better like that as it seemed to expose much more copper as opposed to the skinned off sealed finish. So after the second coat, I sanded it again, and reinstalled it in the boat. That was about 18months ago. No barnacles at all to this day, and it's in a tidal estuary in the tropics. The rest of the boat had some barnacles, not real bad, but noticeably worse than my perfectly clean rudder.

So for copper coat, definitely sand it just before immersing the hull, I reckon you should get at least 2 years out of it. If there is enough on the hull , should be able to sand it back and renew it again. I've just done this to the rest of the hull, but rather than wait and see, I applied an ablative copper antifoul after sanding and hopefully get some extra time up my sleeve once it's dissolved and the copper coat can take over again. Sanding a hull on a muddy beach is hard work btw :)
I'll apply some more when we get it to a proper slipway for other jobs in good time...

Post Reply