For how long will antifouling stay effective on a boat that hasn't been launched?

[NealB]

In keen anticipation of an imminent launch, we applied fresh antifouling on 17th June 2019.

Due to a combination of depressing reasons, the imminent launch still hasn't happened.

The antifouling looks lovely: but will it still be effective, or do we need to apply another coat (we're now hoping to launch in the next couple of weeks)?

 

[Tranona]

Have a look at the data sheet for the product - it will tell you. However the application to launch time for most that I have seen is in months, so yes a new coat is needed.

 

[NealB]

Have a look at the data sheet for the product - it will tell you. However the application to launch time for most that I have seen is in months, so yes a new coat is needed.

Thanks for confirming my own thoughts!

 

[garymalmgren]

My boat was out for a year with almost new antifouling.
I thought that it would be OK.
It wasn't . I mean it REALLY wasn't.
Unfortunately, you have to reapply.
Gary

 

[Neeves]

In keen anticipation of an imminent launch, we applied fresh antifouling on 17th June 2019.

Due to a combination of depressing reasons, the imminent launch still hasn't happened.

The antifouling looks lovely: but will it still be effective, or do we need to apply another coat (we're now hoping to launch in the next couple of weeks)?

The nice thing about your quandary, now answered, is that if you had launched and left your yacht unmoved in the water it would be in a horrible state - boats need to move in order for most AF to work. Sitting stationary for any length of time and you would need to slip her and have her aggressive power washed. All you need do now is add another coat, or 2 of the same AF. Actually I'd change the colour of the new AF and then when the old colour starts to show through you will know its that time again.

Jonathan

 

[Dipper]

My boat was out for a year with almost new antifouling.
I thought that it would be OK.
It wasn't . I mean it REALLY wasn't.
Unfortunately, you have to reapply.
Gary

Mine was good even after 13 months ashore post application. At lift out the following season, there was only some surface slime most of which came off by wiping with a wet sponge. It may depend on the make of antifouling and whether the boat is in a high fouling area. I had used International Micron 350 (expensive but worth it) and the boat is on a swinging mooring in Portland Harbour. Micron is supposedly good for 12 months before launch.

 

[NealB]

The nice thing about your quandary, now answered, is that if you had launched and left your yacht unmoved in the water it would be in a horrible state

Thank you for that much-needed reminder!

Something about "every cloud ", or "always look on the bright side".

 

[coopec]

As Tranona has said "read the data sheet".

I have used Altex no 5 anti fouling and there is no time limit dictating when the yacht is to be launched

 

[William_H]

Well much depends on cost of lifting to reapply if you go ahead without repaint and also if you will be willing to get in the water and scrub or use a scrubbing post on low tide. If it were me I would leave as is and relaunch. But I delight in scrubbing in water and lift costs nothing on the other hand we suffer fierce fouling compared to UK. ol'will

 

[Neeves]

I have never quite understood why AF becomes less effective if not launched within the time period recommended by the paint manufacturer, particularly hard AF. However whilst the copper based active ingredient may (or may not) be stable I can understand that the resins systems may deteriorate (how would I know). But as epoxy deteriorates in UV there is no reason why the resins of AF may not also deteriorate, not necessarily from UV, if not submerged in seawater. I note Coopec's post above regarding Altex but they may not envisage anyone applying AF and then not using their yacht within a few months - why would one anticipate a yacht being left idle for a year - its an expensive asset. And no-one during their corporate strategy sessions will have envisaged a pandemic impacting for 2 years.

Its not very onerous if your yacht is on the hard to apply another coat - its takes at most a few hours (unless you own a Russian super yacht) and the alternative is to launch as is and then regret it - and that will probably be expensive as most slipping costs.

To me its a no brainer - add some more AF - why take the risk.

Jonathan

 

[RivalRedwing]

If you have water available I would just take off the surface layer with a some mesh sandpaper (used wet), preferrably on a pole extension for speed, to remove the surface layer and expose 'fresh' antifoul. Takes a couple of hours for a 34' yacht.

 

[Jim@sea]

Never assume that when you see a boat hull with grey antifouling that it is actually antifouling.
Went to a French boatyard a few years ago where the hull of a boat which was up for sale was being antifouled with grey antifouling, although it wasn't antifouling, they were using Grey Vinyl Silk Emulsion, not for them to spend loads of money on something which was up for sale,

 

[NealB]

Well much depends on cost of lifting to reapply if you go ahead without repaint and also if you will be willing to get in the water and scrub or use a scrubbing post on low tide. If it were me I would leave as is and relaunch. But I delight in scrubbing in water and lift costs nothing on the other hand we suffer fierce fouling compared to UK. ol'will

That is definitely a key part of our algorithm.

Drying out, for a low water scrub and recoat, is pretty easy, cheap, for our boat, round these parts.

 

[NealB]

Never assume that when you see a boat hull with grey antifouling that it is actually antifouling.
Went to a French boatyard a few years ago where the hull of a boat which was up for sale was being antifouled with grey antifouling, although it wasn't antifouling, they were using Grey Vinyl Silk Emulsion, not for them to spend loads of money on something which was up for sale,

In our case, it was us that applied the existing coating.

It definitely said 'Antifouling' on the tin (by a local Burnham company: Quick Shop — Specialist UK paint manufacturer Marine Decorative Industrial and <br/>Protective coatings ).

 

[NormanS]

We antifouled in March 2020, and for COVID reasons, and a broken ankle, didn't launch until May 2021. The copper rich antifouling worked perfectly until lift out in October.