Coopercoat, what to put on the saildrives?

[Rapanui]

On our Athena we use Velox on the saildrives. Effective for 2+ years

[Rumrace]

Interlux on drives and props may have some merit on huge commercial vessels to reduce haul out.
Painting a prop according to Interlux is down right funny. Sure sells product. It’s a band aid to avoid a proper paint job as stated by Yanmar and ZF.

[tamicatana]

Any cogent answer to any anti fouling question will include location. It cannot be overstated how the effectiveness of any given coating will vary depending on location

[fstbttms]

Originally Posted by tamicatana

Any cogent answer to any anti fouling question will include location. It cannot be overstated how the effectiveness of any given coating will vary depending on location

In general, this is quite true. But when it comes to anti fouling paints that can safely be applied directly to aluminum, your product choices are very limited.

[CaptainRivet]

Originally Posted by fstbttms

In general, this is quite true. But when it comes to anti fouling paints that can safely be applied directly to aluminum, your product choices are very limited.

Fully true.
After figuring out that just the final coat of propspeed can be applied directly on the factory coat of the saildrive I went for that.
The factory coat of saildrive when it’s 100% ok without any aluminum showing up acts as primer and is far superior to the propspeed one.
Bukh Bremen sells the final clear coat separately, so 220Euro for 320ml which lasts for 4-6 saildrive legs. Means 35-55Euro a protected saildrive, unbeatable.
And if you need to renew, Fall dry, clean old propspeed with industrial alcohol off, sand with 600grid wet and apply a new clear coat. After 4h it’s cured enough. Perfect

For me Coopercoat was a nobrainer as I had a perfect clean epoxy primer base and no extra preparation cost. All cfk cat.
I had done a complete underwatership Restauration and reinforcement from the bare fibreglass.
Regarding Coopercoat on saildrive or eg lead keel all is fine until a scratch voids the isolated layer.
And the top layer not all Cooper is encapsulated. Also it’s water based epoxy that let water penetrate it. A proper insulation eg epoxy primer is required between hull and Coopercoat

[fstbttms]

Originally Posted by CaptainRivet

For me Coopercoat was a nobrainer...

Good luck with it. I wouldn't wish it on an enemy.

[CaptainRivet]

Originally Posted by fstbttms

Good luck with it. I wouldn't wish it on an enemy.

Well all my buddy boats have it, some since 9 years and no issue at all. Working well.
The oldest ones will definitely do another 2-3years so 11-12years.

[fstbttms]

Originally Posted by CaptainRivet

Well all my buddy boats have it, some since 9 years and no issue at all. Working well.
The oldest ones will definitely do another 2-3years so 11-12years.

Durability isn't the issue. The stuff is straight epoxy- of course it lasts a long time. The question is how well does it retard fouling? In my experience, very poorly.

[CaptainRivet]

Originally Posted by fstbttms

Durability isn't the issue. The stuff is straight epoxy- of course it lasts a long time. The question is how well does it retard fouling? In my experience, very poorly.

They done all well. Major issue is when it's not reactivated. It's not put on and forget about it the next 10 years. Most of my buddies go over it once a month with a black scotchbride pad to remove the slim layer and reactivate at the same time. Some only every 2-3month and one hulls out yearly and activates before going in, that looks the worst but still ok.
Only have around 60cm draft on the hull and then 50cm mini keels, go every morning swimming anyhow and normally once a weak just do half a hull with the snorchel. Done that with the Jotun racing hard antifouling too. Worked well too. To make it more effective you can add 100 or 200g more Cooper per Liter, they are limited buy the law to 2kg but already 100g more makes a noticeable improvement. What I done...

Its water based Epoxy.. A bit different then standard Epoxy, eg it's not a 100% barrier like Epoxy. The Epoxy they use is for sealing concrete floors in industrial building, I know exactly what manufacturer and specs they use... Extrem margin....a 100l barrel costs them 700Euro,meane 7 Euro per Liter and they charge 70Euro...
Good if you have to do it new, you just sand and put another 6 layers on, not scraping that old stuff off.

[David B]

Originally Posted by ItDepends

Coppercoat is priced so that it makes economic sense only if it reduces the hauloout frequency. On myboat, I need to haul out every 800 engine hours or 2 years (at least) to replace a prop shaft seal. So for me, there is really no reduction in hauling costs if I was to use Coppercoat. So it really makes no economic sense, for me. If you can haul once every 5 years, them maybe it works for you.

If you are using propspeed on your prop, or drive unit you will need to renew that at least every 24 months... or spend a LOT more time and money on clearing your running gear... look carefully at the economic assumptions around Coppercoat. It makes sense for some, but NOT for all...

Checked the price of bottom paint recently?

[CaptainRivet]

Originally Posted by David B

Checked the price of bottom paint recently?

Yes they went up. Agree Coopercoat doesn‘t make sense for everyone.
The costs to prepare the underwatership for Coopercoat are significant till huge so this together with Coopercoat price itself makes a hefty pricetag.
And who is hauling out yearly or all 2 years anyhow because of needed maintenance eg propshaft seal plus the huge preparation costs then a good hard antifouling makes more sense. Had that on my old mono ketch, so went for Jotun racing which worked well for 3-4 years, so replacement every 2nd haul out. Plus the surface of the underwatership was huge, the Coopercoat cost would have been huge too.
On my cat totally different: done a osmosis treatment plus reinforce of the hull so underwatership was blank anyhow, so the price difference was just double of antifouling paint cost. Not much underwatership Surface too, 17l of Coopercoat was good for 7 layer on a 40ft cat, Lagoon 400 needs 22l for 6 coats. Plus saildrive maintenance from on top so I don‘t need to haul out for any maintenance at all (all through hulls composite and new). And redoing the saildrive legs with propspeed with just the final coat can be done when falling dry and without a big mess. In that combo Coopercoat is a nobrainer.

[NevilleCat]

I'm confused as you keep calling it Coopercoat.
Is this a different thing to Coppercoat?

[CaptainRivet]

Originally Posted by NevilleCat

I'm confused as you keep calling it Coopercoat.
Is this a different thing to Coppercoat?

???? Don't get your issue here

[NevilleCat]

Only that I initially assumed it was just a spelling glitch or weird auto-correct issue, but then was wondering if it was another local formulation similar to the British Coppercoat...we have one in Aus that has been around for 30 years or so.
Judging by your response I guess not.

[CaptainRivet]

Ahh Right.. F... Autocorrect its the original Coppercoat from the brits...
Now correctly written...