Hadenough
Well-Known Member
Assuming of course that you haul out every winter with the associated craneage and laying up costs.
4 coats of cheaper antifould v 2 coats of expensive stuff?
- Thread starter seanfoster
- Start date
Assuming of course that you haul out every winter with the associated craneage and laying up costs.
Sticky Stuff
Well-Known Member
The question about the of the number of coats is totally dependent on the actual thickness achieved and the rate at which the product depletes in relation to the amount the vessel is used, the speed at which it is used and other similar factors like how much water flow does it get when not in use ect ect.
Nearly all Antifoul development is focused on the rate at which the surface washes away and in doing so how much new copper and biocides are exposed to the water (The active layer).
Anyone who thinks antifouling is just about the copper content and poison is mistaken and very out of touch with how modern antifoulings work... you could have the highest copper content and the most powerful poisons but unless these are exposed to the water they will have a far lesser effect.
In most cases copper fights the shell life like barnacles and the other added biocides fight slime ect.
Just look at epoxy/copper products they don't add biocides to fight slime so inevitably build up slime, even if they did add biocides how could they be constantly exposed when insulated within a hardened waterproof epoxy resin ? Even to keep the copper content exposed they should have to expose it manually with abrasives
Thickness can be controlled by the applicator:
1 Heavy coat applied by someone can easily be equal the same as 2 light coats applied by another.
1 coat applied in the cold can be much much thicker than 1 coat applied in the warm due the difference in viscosity of a product at different temperatures.
I have seen people thinning the product and also rolling it out really thinly 'to make it go round' this may work initially and often fairly well but it should not be expected to last very long.
Thickness can also be controlled by the manufacturer:
Some products are very thick and formulated to be sprayed/pumped
some are relatively thin and designed to be rolled by hand.
Soft /Hard
There are both soft and hard products, for us yachties this is usually kept simple and is the difference between a Hard racing product and a self polishing product
However there are vast differences in the wash rate between the self polishing products. This is not really softness but we all just relate to it that way.
If you have a relatively 'soft' product that washes easily it will often give very good performance but for a short time. Because of this it would need to have the extra thickness to allow it to work for the extended time.
A vessel with a high use at good speeds often find the whole antifoul layer depleting to almost nothing and will often have a very good performance, they can often use a cheaper product, as long as they have applied enough thickness to last the time being used in the water
Any vessel with low use and low speed will inevitably not get the same efficient washing process.
Leach layer:
A leach layer will develop on most, if not all antifoulings, especially if you are not getting enough of the washing process.
A leach layer is the part of the product (on the surface) that has not washed as efficiently and has also depleted most of its active content, to make it worse ...this layer starts to insulate the good stuff underneath from water exposure and the antifouling becomes less effective.
Rarely is it ever necessary to remove the whole build up of old self polishing antifoulings, however it is often very beneficial to remove the surface (leach layer) if one has been allowed to develop through low use ect.
Most of the time at the end of a season on lift out (while still wet) a really hard jet wash will do enough to remove any leach layer.
Some cynics and cheapskates can see this as removing good antifouling because they see the colour come off onto the floor, however in most cases this is mostly the inert colour pigments.
The people that rarely complain about their antifoulings are the ones who cover all the bases by choosing a high strength product, apply enough to last and use the vessel enough to allow the wash process to work efficiently.
The ones that often complain are the ones that buy a cheap and completely unsuitable product for their needs and then compound the issue by saving money by not applying enough anyway.
Nearly all Antifoul development is focused on the rate at which the surface washes away and in doing so how much new copper and biocides are exposed to the water (The active layer).
Anyone who thinks antifouling is just about the copper content and poison is mistaken and very out of touch with how modern antifoulings work... you could have the highest copper content and the most powerful poisons but unless these are exposed to the water they will have a far lesser effect.
In most cases copper fights the shell life like barnacles and the other added biocides fight slime ect.
Just look at epoxy/copper products they don't add biocides to fight slime so inevitably build up slime, even if they did add biocides how could they be constantly exposed when insulated within a hardened waterproof epoxy resin ? Even to keep the copper content exposed they should have to expose it manually with abrasives
Thickness can be controlled by the applicator:
1 Heavy coat applied by someone can easily be equal the same as 2 light coats applied by another.
1 coat applied in the cold can be much much thicker than 1 coat applied in the warm due the difference in viscosity of a product at different temperatures.
I have seen people thinning the product and also rolling it out really thinly 'to make it go round' this may work initially and often fairly well but it should not be expected to last very long.
Thickness can also be controlled by the manufacturer:
Some products are very thick and formulated to be sprayed/pumped
some are relatively thin and designed to be rolled by hand.
Soft /Hard
There are both soft and hard products, for us yachties this is usually kept simple and is the difference between a Hard racing product and a self polishing product
However there are vast differences in the wash rate between the self polishing products. This is not really softness but we all just relate to it that way.
If you have a relatively 'soft' product that washes easily it will often give very good performance but for a short time. Because of this it would need to have the extra thickness to allow it to work for the extended time.
A vessel with a high use at good speeds often find the whole antifoul layer depleting to almost nothing and will often have a very good performance, they can often use a cheaper product, as long as they have applied enough thickness to last the time being used in the water
Any vessel with low use and low speed will inevitably not get the same efficient washing process.
Leach layer:
A leach layer will develop on most, if not all antifoulings, especially if you are not getting enough of the washing process.
A leach layer is the part of the product (on the surface) that has not washed as efficiently and has also depleted most of its active content, to make it worse ...this layer starts to insulate the good stuff underneath from water exposure and the antifouling becomes less effective.
Rarely is it ever necessary to remove the whole build up of old self polishing antifoulings, however it is often very beneficial to remove the surface (leach layer) if one has been allowed to develop through low use ect.
Most of the time at the end of a season on lift out (while still wet) a really hard jet wash will do enough to remove any leach layer.
Some cynics and cheapskates can see this as removing good antifouling because they see the colour come off onto the floor, however in most cases this is mostly the inert colour pigments.
The people that rarely complain about their antifoulings are the ones who cover all the bases by choosing a high strength product, apply enough to last and use the vessel enough to allow the wash process to work efficiently.
The ones that often complain are the ones that buy a cheap and completely unsuitable product for their needs and then compound the issue by saving money by not applying enough anyway.
Tim Good
Well-Known Member
Doesn't really address the question directly but if you're in an area where you get to swim in summer then I always find 1 coat of decent antifoul is enough if I am using the boat relatively regularly and manage to give it a gentle scrub in August whilst swimming.
I couldn't even imagine putting 4 coats and even if I could be bothered I'm not sure it would help as that theory assumes it would erode twice as fast as a premium brand.
I couldn't even imagine putting 4 coats and even if I could be bothered I'm not sure it would help as that theory assumes it would erode twice as fast as a premium brand.
seanfoster
Well-Known Member
Well I'd love to but not on this boat! I'm planning to use her for the next two seasons and then move up to something bigger.
seanfoster
Well-Known Member
Thanks for your very detailed post, it makes a lot of sense!
Derm
Active Member
Yes that is a good reply by sticky stuff and I agree with your latter comments.
[70521]
Well-Known Member
Like you have removed all the old AF.
I am sticking to the cheap stuff and hope that the JetWash will remove what little is left next winter.
I am sticking to the cheap stuff and hope that the JetWash will remove what little is left next winter.
Sticky Stuff
Well-Known Member
Please consider that a cheap product may not deplete at a faster or slower rate.
Faster or slower depletion is not usually a consequence of manufacturing cost.
Antifouling manufacturers are doing their best to suit all types of vessels within 3-4 products in their average range and this may or may not always be best for everyone.
The cost of this type of product is usually and in the most part related to the copper and biocide content.
As I have said before a cheap product will often work really well on some vessels.
The erosion rate (or softness for us yachties) of a product is not normally given away by the manafacturer, you just have to try them to see.
You can look at a data sheet to see how much active content they have though.
I always like to the appearance of thin areas on lift out at the end of the season, this tells me I am using it enough and washing well, however I have to balance that with it getting to thin before the end of the season.
This has happened before and I just apply the coat a little heavier next year to adjust.
Faster or slower depletion is not usually a consequence of manufacturing cost.
Antifouling manufacturers are doing their best to suit all types of vessels within 3-4 products in their average range and this may or may not always be best for everyone.
The cost of this type of product is usually and in the most part related to the copper and biocide content.
As I have said before a cheap product will often work really well on some vessels.
The erosion rate (or softness for us yachties) of a product is not normally given away by the manafacturer, you just have to try them to see.
You can look at a data sheet to see how much active content they have though.
I always like to the appearance of thin areas on lift out at the end of the season, this tells me I am using it enough and washing well, however I have to balance that with it getting to thin before the end of the season.
This has happened before and I just apply the coat a little heavier next year to adjust.
Plevier
Well-Known Member
Now that I can't get the Jotun stuff (boo! hiss!) that gave premium performance at economy price I've been wondering what to use and have been looking at the MSDS's for various products to see what's in them.
There's a difference that Sticky Stuff hasn't mentioned.
It's noticeable that all the economy ones (Flag, EU45, Mare Nostrum) just rely on copper. My understanding is this will discourage barnies etc but not deal with slime.
The posh ones (Micron extra, Seaforce, Non Stop etc) include a more aggressive biocide as well typically dichlofluanid or Zineb. This should cope with the slime.
Whether that is the major factor in the price difference I don't know. Maybe those chemicals are incredibly expensive.
Oh hang on, the Jotun commercial products that we can't buy now include them too. No, we're just being stuffed.
Anyway, it does mean that putting on twice as much cheap stuff won't make it equal dear stuff.
There's a difference that Sticky Stuff hasn't mentioned.
It's noticeable that all the economy ones (Flag, EU45, Mare Nostrum) just rely on copper. My understanding is this will discourage barnies etc but not deal with slime.
The posh ones (Micron extra, Seaforce, Non Stop etc) include a more aggressive biocide as well typically dichlofluanid or Zineb. This should cope with the slime.
Whether that is the major factor in the price difference I don't know. Maybe those chemicals are incredibly expensive.
Oh hang on, the Jotun commercial products that we can't buy now include them too. No, we're just being stuffed.
Anyway, it does mean that putting on twice as much cheap stuff won't make it equal dear stuff.
Derm
Active Member
Good point and as I have said Micron Extra 2 was very good here on the Hamble. I shall be buying it again.
charles_reed
Well-Known Member
My experience was that the 1/2 yearly rub-down with wet and dry were considerably more time and effort consuming than antifouling.
My boat came with the original Scott Bader Coppercoat. I put up with it for 3 years and then went for antifouling.
One coat only needs 2.5 litres - the local AF I'm using costs €28 for 2.5 litres. Hauling out to rub-down would cost x6 that amount.
I hope that answers your question?
jwilson
Well-Known Member
I can only assume you are moored in a low fouling area, or somewhere you alternate fresh and salt water, or some very polluted water. Or do you sit in mud half the time. In most places no AF is not a viable option - in 3-4 months in Falmouth with no AF you'd have a a lot of growth that would need much more than a quick brush to get off.
I use expensive AF, but am very mean with it, one thin coat all over plus a second round the waterline and on keel and rudder leading edges. 2.5L for a 35 ft boat each year. Rub down with wet and dry mesh before applying. 10 years on hull still fairly smooth and still sails well at the end of an Easter-end Oct season in a high fouling area. On launch at Easter with a clean freshly antifouled hull and prop full throttle gives me 7.9 knots, by haulout it's usually down to 7.3-7.5 with all over slime, and a few tiny tendrils of weed, maybe half a dozen small barnacles some years, though sometimes none. Except the very bottom centre of the keel of course, which is near impossible to clean/antifoul properly in the 10 minutes between the Travelift picking the boat up and dropping her in the water. That usually has quite a crop of all sort of wildlife.
LONG_KEELER
Well-Known Member
What a great post. And how apt for this time of year.
Ok lads ! Start looking at data sheets. I know I will. Plus, don't forget your leech rate.
The many variables in application, brand, location, and sailing use explain why so many people have different experiences. Personally, I have noticed a big difference in fouling between a marina berth and a swinging mooring. The marina berth clearly has slower moving water, shade from the sun, coupled with next door neighbors.
We may also possibly underestimate slime as not being too much of a factor. A neighbour of mine has a planing powerboat and can notice immediately when there is slime both on the plane and at hull speed.
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Sticky Stuff
Well-Known Member
Having checked I can assure you all that the major manufacturers of antifoulings have Professional only registered products that most of us can't have and also amateur products that all of us can have..
If we are to give one of them a hard time for complying with their legal requirements lets do the same with the others as well.
Boo Hiss !!
They are all trying to stuff us as Plevier is saying ...
Whats up with some people !
If we are to give one of them a hard time for complying with their legal requirements lets do the same with the others as well.
Boo Hiss !!
They are all trying to stuff us as Plevier is saying ...
Whats up with some people !
Plevier
Well-Known Member
Yes they are all doing it. However Jotun didn't before it's a shame they have now vigorously joined in.
When you look at the MSDSs for the professional stuff and compare them with the amateur ones, they are all very similar. The same nasties occur in both. There is no consistent difference.
So how is it justified?