Hey fellow sailors,
Two years ago I posted here promising to develop a DIY antifouling paint that outperforms the top-shelf stuff and I'm stoked to say: mission accomplished.
After years of testing, collecting samples from boats at Woolwich Dock, and tweaking formulas, I've finally built a mix that consistently outperforms Sea Hawk paint including their top formula with 40% copper and 2.5% zinc pyrithione.
My upgraded mix is based on Pettit ViViD, and here's what it looks like: Copper: ~27% total (1kg added copper powder, 320 mesh) Zinc Pyrithione: ~5.3% total (add 500g) Octhilinone: ~0.47% (1L anti-mould paint additive 82g/ Octhilinone per L)
Originally vivid petite contains : Copper 18%Zinc 2.8%Octhilinone none (but Altex 5 plus contains 1%)
To mix it (per 10L of Pettit ViViD): Add 1kg copper powder (~$70 on eBay) Add 500g zinc pyrithione (~$80 on eBay) Add 1L anti-mould paint additive (Protite, ~$160 at Project Painting, Gladesville - opposite Aldi or double price at Bunnings). Stir well. Use same day. Stir often while rolling.
Results?Better slime resistance, stronger performance over time, and surprisingly less environmental impactthan some of the harsh U.S. formulas such sea hawk.
Disclaimer: This is just my personal project. I'm not selling anything and not advising anyone to break any rules. Use at your own risk, and please keep it quiet - I'm not looking to stir up trouble with the authorities or suppliers. If budget is tight Altex 5 plus us with 500g of zinc phyriotine will do the trick but not effective as petite after 9 months. I am still convinced that coppercote is the way to go for 10 years headache free but it's expensive and knowledge is needed to apply it properly. I have no affiliation with any suppliers or paint companies, the aim is to save few bucks to my fellow sailors by keeping their paints more potent and their hulls cleaner for longer. This mix is not breaking any regulatory barriers, is just very well balanced.
My next project would be to modify Hempel Olimpic 72900 paint as it looks promising just like petite vivid. I will need to use some teflon powder to modify that one. Talk to you back in few years time.
Thanks to everyone who followed the original thread, you kept me motivated to finish this. Wishing you all smooth sailing and clean hulls! Fair winds my friends and family.

Coppercoat the way to go - hold on there partner.

I put Coppercoat on my cat in October and it has been pretty dreadful. I am still working with the retailer to get it to work but it was a truly terrible job to prepare the hulls and it has worked about as well as 2 year old antifoul. I have built 4 boats using epoxy and know how to apply epoxy. If I can't apply it properly then there is something wrong with the product.
I wanted it to work so badly - still do but have started getting used to seeing little barnacles 2 weeks after the last scrape.
So don't think Coppercoat will work - it doesn't for most users I have been in contact with, yet it works for some - it is highly frustrating.

Dear Partner,
It took me three years to get Coppercoat working effectively on my test samples. When mixing copper powder with epoxy, I also added zinc pyrithione to promote copper oxidation. I'm curious-what ratio are you using? And did you sand the epoxy after application?
I'm still undecided whether I should drive to Guildford and get myself 20 kg of copper powder, some epoxy, and zinc pyrithione, and apply it to my boat-or experiment with Pettit Vivid and some additional components.
My Coppercoat application has been working well since 2011 and is still performing. Take a look at the photo of my boat from last December-it speaks for itself.
However, the best option, my dear partner, might be Hempel's Silic One. You only need to add one extra coat every two years, and the hulls come out spotless. When I saw it in action, I couldn't believe my eyes. I even tried to stick tape to it-it wouldn't adhere. This might truly be the future, for all of us-my dear family and friends. Out of 109 samples all performed differently each year. Complete nonsense and impossible to standardise the results. Silica one uses No chemicals, pure silicone and it works regardless of amount of rain or sunny days we are having. How good is that for our ecosystem!!! If anyone knows how to get in touch with Hempel representatives please advise. I am strongly advising silica one if budget permits. Eventually we will all end up using it one day or another. I hope this helps my dear partner and yes not surprised at all that your Coopercote is not working, sometimes works sometimes not. I was lucky with my boat ( see the photo) but now is time to move on towards silicon and stop messing around with such strong chemicals. Stay strong my partner. Avoid warm beer and cold women.

Not too bad for 14 years old coppercote. Now is time for silicone .

I put the new Jotun product that replaced Seaguardian on my boat in December. Three good coats rolled on and barnacles after 2 months. Not happy

Hempel store at Padstow Sydney. Ask for Silca one apply this and you will be like a king with slime free for two years.. the best possible thing you can do for your boat and your engine.
The rest is all waist of time and money. Trust me I am a medical doctor and have chemistry in my pocket. Danish engineers done the great job with Silca one and we should not be inventing hot water here.
3 years of sampling and conclusion is : silicon is the future mate.
Ciao Tigers.

Serb, boat looks cool, post some more pictures!

After light sand to re activate the copper but unfortunate not much left to activate. 15 years is 15 years. But still barnacles free from December ( except the rudder). Decided to go with Hempel Tie Cote primer and Globic 9000 also from Hempel. An excellent product, a bit dearer but works well for 6-7 years. Silc one is not allow in Australia any more. Not fair on us.

Gday Serb

I didn't realise you were using Coppercoat - I thought you were having problems because you needed a diver and he was around every couple of weeks. So does the Coppercoat work on your boat? Why not put more on if it works well? It is not hard to apply - just hard to pay for and hard to prep.

Hi Serb. Agree Silica is the future but do you know why it's not allowed in Oz?

Select to expand quote

Serb1980 said..
Hey fellow sailors,
Two years ago I posted here promising to develop a DIY antifouling paint that outperforms the top-shelf stuff and I'm stoked to say: mission accomplished.
After years of testing, collecting samples from boats at Woolwich Dock, and tweaking formulas, I've finally built a mix that consistently outperforms Sea Hawk paint including their top formula with 40% copper and 2.5% zinc pyrithione.
My upgraded mix is based on Pettit ViViD, and here's what it looks like: Copper: ~27% total (1kg added copper powder, 320 mesh) Zinc Pyrithione: ~5.3% total (add 500g) Octhi

Thank you very much for that helpful advice.

Where in Sydney do you slip your boat so that you are allowed to put your own anti-fouling on?

Fairly certain Woolwich Dock where he is moored near. Also WD is mentioned in his post text. You can do your own work there. In my experience though their water blaster pressure is way too low - maybe to satisfy environmental issues but I am not sure. See here some "info";
woolwichdock.com/services/
I reckon when I slipped the pressure they used must have been wound down to ~3.5bar (=50psi like your garden hose) but I have no recording of this - just asked them why the result wasn't as I had expected and had received at other slipways - answer "that's what it is mate".