Is it wrong to jetwash antifoul?

Polly's Kettle

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I applied the new micron 350 last year. Fairly good results - I put more on another thread recently.

My question here is about advice that I got from the manufacturers, International, when I sent in my feedback, being one of the first in the UK to have results with this new product.

If given sufficient coats, the product will last 2 years before needing new antifoul. I had mine back out of the water after 14 months to change anodes and jetwash the slime off.

International have told me that I shouldn't have jetwashed it, that I should use a sponge at most, otherwise it will come off. I thought that everyone gave their boat a jetwash …. or is that just because they are about to sand & paint with new antifoul so losing some of the old stuff doesn't matter?

I must say that I didn't notice any antifoul being abraded as a result - the stuff is like hard tar.
 
If given sufficient coats, the product will last 2 years before needing new antifoul. I had mine back out of the water after 14 months to change anodes and jetwash the slime off.

International have told me that I shouldn't have jetwashed it, that I should use a sponge at most, otherwise it will come off. I thought that everyone gave their boat a jetwash …. or is that just because they are about to sand & paint with new antifoul so losing some of the old stuff doesn't matter?

I must say that I didn't notice any antifoul being abraded as a result - the stuff is like hard tar.

I guess it depends on how powerful the jetwasher is. When my boat was lifted in July, the marina washed the hull with their industrial jetwasher, and it certainly removed some of the old Micron antifoul - which I don't mind as I want to avoid build-up. I've used Micron for years, with a solid 2 years afloat between applications, and it seems to last well. I've just re-antifouled with Micron 350, so I look forward to seeing it last just as well. It didn't seem markedly different in texture from the previous Micron.
 
I applied the new micron 350 last year. Fairly good results - I put more on another thread recently.

My question here is about advice that I got from the manufacturers, International, when I sent in my feedback, being one of the first in the UK to have results with this new product.

If given sufficient coats, the product will last 2 years before needing new antifoul. I had mine back out of the water after 14 months to change anodes and jetwash the slime off.

International have told me that I shouldn't have jetwashed it, that I should use a sponge at most, otherwise it will come off. I thought that everyone gave their boat a jetwash …. or is that just because they are about to sand & paint with new antifoul so losing some of the old stuff doesn't matter?

I must say that I didn't notice any antifoul being abraded as a result - the stuff is like hard tar.

It is an erroding antifouling with the surface being erroded by the flow of water when underway. A pressure washer will errode it much faster so wasting antifouling if done between applications. I use the same and when I dry out on the scrubbing posts, usually just for a prop clean and anode change, I use only the lightest wipe with a soft brush to remove any film if necessary. After 2 years the yard pressure washes which removes any build-up.

Www.solocoastalsailing.co.uk
 
International have told me that I shouldn't have jetwashed it,

Whereas last year they told me querying just this with regard to Ultra 2, in an email,

"You can scrub or jetwash Interspeed Ultra as it is a hard antifouling for the purpose of fast speeds and easily cleaned.

Regards"

And most of it came off after one wash.
 
If it is an eroding or ablative antifoul then jet washing will remove some of the AF - that's how they work. If the AF is working - in theory you should not need to wipe down, but in practice, theory and practice are often different.

The AF may appear 'tarry' but it is how it 'feels' in water that is important - ablative AF tends to feel slimy.

I would be very cautious of any claims that any AF will last 2 years - and I'm surprised International make such claims (unless they have some magic formula not used by the any of the suppliers). Its not a very useful claim anyway - unless you have scrubbing posts or can dry out (and the environmental issues are closing this down) then you will inevitably have to slip to treat your prop and renew anodes. Slipping costs are major part of applying in AF and you may as well buy a slightly cheaper AF to match the service interval needed for the other items.

Fouling is dependent on the amount of AF you apply, the type of sailing you do, how fast you sail, where you keep your yacht and the water temperature. As International control*none of these - I think they will be open to much criticism. Some of the AF companies make different AF, for commercial vessels, some for high speed, some low speed, some prologued periods of inactivity. As many of our yachts sit idle for weeks, if not months, some can average 10 knots or more etc - it would be strange if an AF was developed to offer 2 years life for all of these.

A hard jetwash prior to renewing the AF is a very good idea as it will reduce the amount of build up. But the paint washed off is paint you paid for!

Jonathan
 
I would be very cautious of any claims that any AF will last 2 years - and I'm surprised International make such claims (unless they have some magic formula not used by the any of the suppliers). Its not a very useful claim anyway - unless you have scrubbing posts or can dry out (and the environmental issues are closing this down) then you will inevitably have to slip to treat your prop and renew anodes. Slipping costs are major part of applying in AF and you may as well buy a slightly cheaper AF to match the service interval needed for the other items.

Fouling is dependent on the amount of AF you apply, .....

I've been using a 2-year cycle for many years, initially on a shaft-drive Hallberg-Rassy, and now on my saildrive Bavaria. I use International Micron, and apply it generously with a brush - the secret to antifoul longevity is putting enough on! It's not essential to lift the boat annually to do the prop and anodes. Anodes last at least 2 years. I coat the prop (and now the saildrive leg) with Trilux, here's what it looked like immediately after lifting in July this year, after 2 full years in the water...

saildrive.jpg
 
We use Velox on the Saildrive and props and are lucky if we get 12 months.

Different waters, different types of fouling, different rate of fouling.

We use Jotun Quantum Ultra and get 2 years, 2 generous coats with a roller - but the anodes last 12/16 months.

Fortunately we can dry out anywhere flat.

Jonathan
 
I would be very cautious of any claims that any AF will last 2 years -

The Jotun one I use is specified for 36 months and they do others for longer periods but I just apply one thin coat annually after lift out and power washing to remove slime then light sanding if needed.

Problem with power washing is sometimes an incompetent operator who doesn't keep the jet at a constant distance and pressure, over blasting some areas so the hull winds up looking like craters on the moon.
 
Surely in each case Jet washing can be good or bad depending on the antifouling used and the power of the jet wash etc.
It is definitely wrong to say that 2 years life is not realistic or should not be believed, go to Palma, the antifoulings they use there last much longer.

Commercial ships seem to go 5 years using self polishing antifoulings.
All the main antifouling makers seem to have these products for commercial ships which all seem to work mostly to their claims regarding their time in the water.

All shop products I know of (even the cheaper products) seem to work quite well over this short time frame but there are also more expensive products in the shop that can and mostly do last 18-24 months in the water as long as enough is applied. Micron 350, Seajet Shogun, Hemple Tiger Extra and Jotun NonStop II etc ( I was talking to a guy in Eastbourne the other day and they seem to get 18 months easily enough, he had Seajet )
There also seem to be long-life yacht antifouls but only sold to boatyards ... micron 99, Jotun Supreme, Hemple NCT etc.
There is also a product from Jotun called Mega-yacht that works for 3 years with a guarantee but I hear it is crazy expensive and difficult to get hold of.
I have heard that the RNLI are having Jotun Mega-yacht applied and some have been lasting more than 3 years.
I know that superyachts in Palma use micron 99 and Jotun mega-yacht antifoul and they seem to do what the makers say.

I have been told that jet washing is good if I am drying out for the winter as long as I have applied enough in the first case to make sure I get rid of the invisible slime that turns white when it dries out as this can stop it working as well the next year.
I was also told that much of the black colour I see coming off when I jet wash was mostly the dead layer, this seems to make sense as the antifouling seems to work as new after I jet wash as long as I always have some left

Jet washing works for me.
 
Bit of a sweeping statement. My Darglow anode doesn't make it to 18 months, by which I mean it falls off due to wasting around the bolt holes. And that's with a galvanic isolator and no proximity to 230v in my home home berth.

I jet off mid season and know many boats who do the same with no ill effects. It is, however, imperative to use the correct nozzle, correct pressure, and an operator with a soft touch who knows when to back off. If there is any attached weed, this should be also pulled off by hand.

Aside from that, might I ask if that is their in-house Featherstream prop and if it's been painted, with what?

BTW, is this a fully isolated prop? In which case eroding its fairly chunky anodes seems a surprise.

And if you don't mind, how would you rate it on say a 1-10 scale as I'm considering one?
 
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Bit of a sweeping statement. My Darglow anode doesn't make it to 18 months, by which I mean it falls off due to wasting around the bolt holes. And that's with a galvanic isolator and no proximity to 230v in my home home berth.

I've found the Featherstream anode will last 2 years by antifouling the bolt holes to insulate the bolts. Lots of contact area around the base so it still works OK.
 
Bit of a sweeping statement. My Darglow anode doesn't make it to 18 months, by which I mean it falls off due to wasting around the bolt holes. And that's with a galvanic isolator and no proximity to 230v in my home home berth.

I was talking about saildrive anodes. I'm aware that some folding props tend to eat anodes.
 
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