The chemistry of antifoul paint?

  • Thread starter Thread starter jfm
  • Start date Start date
20 litres sounds about right for 3-4 coats of a 60 footer, which is what Interspeed are suggesting for Micron 66. I might give it a try, if it works i'd save the extra cost of the a/f in lifting charges and fuel. Maybe we could haggle for a discount for 2 tins?
 
What about trailer boats???

My boat spends most of its time on the trailer - does AF need to be kept moist to work . . . . . if the boat is not in the water much - is it really a cometic thing to look good.
 
I was in Antibes today (your boat is fine btw, though needs antifouling!) but paint shop was shut (saturday/winter thing...) I'll find out the price anyway. I only want 2 coats max on mine. I have a very good guy who books the crane and hardstanding and applies the paint and does anodes. Shall I put you in touch?
 
I spoke to Sunseeker today about Micron 66 and they can do it on our 72.

This is what they said about application.

[ QUOTE ]
After speaking to Antifouling department. They tell me that they would apply the usual International Primocon as a base primer and one coat of Interspeed ultra which is a hard racing antifoul. The International Micron 66 is a self eroding antifoul and would need 3 or 4 coats (depending on advice from International) Once the Micron 66 has eroded then the Interspeed would show through giving an indication on when re-application is required.

[/ QUOTE ]
 
I dont see the point of the interspeed. Without it, once the micron 66 has worn thru you will see the primer and that tells you you need paint?

I'm only gonna put 2 coats of m66 on I think, over my existing old interspeed
 
I dont think technically that can be done.
If you check out the international site there is very specific details about what af needs primer and which do not.

66 quote
'MAJOR REFURBISHMENT: The first coat of Micron 66 should always be applied over a recommended anticorrosive primer system. The primer surface should be dry and free of all contaminants (oil, grease, salt etc) and overcoated with Micron 66 within the overcoating interval specified for the primer.
REPAIR and UPGRADING APPROVED SYSTEMS: Degrease the surface. Clean the entire area with controlled high pressure washing (3000 psi./211 bar). Repair corroded areas with the recommended anticorrosive primer system (Primocon or JVA202). '

My post above was not half baked.
I spent a lot of time last year researching and came to the conclusion

a very cheap soft af will stick to anything and work the best in that it washes off along with any thing stuck to it.
the following year you have to either add more soft (but then any areas left untreated have zero protection)
or strip back and prime.

Uno is one of a few that do not require a primer and so a build up of af is hopefully reduced, ie/ each year you add one coat that hopefully wears down, instead of adding 3 coats (primer +2)

I let my last boat build up and even a quality primer will not hold thick coating together and it flakes off.
 
Thanks Daka. Hmmm. I took Nonitoo's info http://www.ybw.com/forums/showflat.php/Cat/0/Number/1703143/an/0/page/0#1703143 to mean m66 could be painted over interspeed.

paint manufs tend to be ever so fussy in writing about what paint will stick to what surface and frequently they say primer is needed. Imvho this is perhaps to cover their own backsides ref prod liab claims, and to sell more paint. I betcha m66 can be painted straight over interspeed no probs!
 
An opinion if I may?

Bottom line, A/F is a mix of Copper & Biocides, plus the paint bit, the copper for the barnacles,the biocides the weed. The darker the colour of the A/F, the more effective it is, as the main ingredients that do the work are not being diluted with pigment (Black very good , Red /White Not so good).
Hard A/f is ideal for fast powerboats (25knts plus) that are REGULARLY used, 60hrs plus or at least weekly.
The softer A/f for slower boats . A/F works by the the copper/ Biocide contents being exposed to the water, if left left for long periods without use the external surface expends it's active ingredients, both copper and biocide and will become inactive, this obviously results in growth of one form or another.The result is the lift and clean and usually a not necessary recoat of A/F ( very rule of thumb). If you use your boat regularly both hard and eroding A/F will give good service possibly up to two years. International Micron Extra ( Micron 66? ) are both eroding A/F, give the boat 2 coats and it should last you 2 yrs or so dep[ending on usuage, the advantage of a soft A/F against the hard A/F is it will wear away so you end up with very little A/F on the hull after 2yrs, therefore very little build up and the reduced need for expensive A/F removal treatments /systems, a distinct advantage against the hard A/F. If your hull has not had the A/F removed back to the Gel Coat in the last six years or so it is time to think about it, as the first layer will now be "dying" and it's adhesion weakening and it will start to flake your newly applied A/F.

Just an opinion the way I see it.
I really cannot see the need to A/F every year.
Not bad coming from a Swindlery Owner and Antifouling is part of My living
I stand to be corrected, but this is how I have observed it to be over the the last 5 yrs hear in Swansea.
 
I read that info quite differently, and I think it may have been taken from some guidance for steel hulled boats.

The first paragraph relates to major refurbishment, and I think the assumption then is that all existing a/f has been removed, therefore it states that a primer is required before overcoating with M66, as you'd expect. For repair/upgrading it states you only need to power wash (and repair any corroded areas, which is not relevant for 95% of us on here). That suggests to me it can be applied directly over exsiting a/f, so long as its not flaking and is compatible.

Why would you apply a new coat of primer each year? Why not just use the same a/f then you don't need to worry about compatibility, just powerwash and apply one or two coats of new a/f. If the old a/f has completely worn off then it will only have exposed the original primer so still OK to just slop on some new a/f?
 
Yup but I'm having a cynical week. An antifoul manufacturer who makes his living from selling very expensive paint telling me I need primer then 4 coats, or all hell will break loose? Nah thanks :-)

I'll just slop 2 coats of m66 on top of my exisiting Interspeed, after a jetwash. Hey it's no big deal if it all flakes off, easy to get a mid season crane out and more paint. My interspeed is black and the new m66 will be black, so I wont easily be able to tell when the m66 has worn through, but no matter
 
Actually I'm not convinced by the need to see whether the M66 has worn through by using a different colour base coat. Surely on the areas it has worn through there will be growth so pretty obvious?
 
just seen this. Must be an incredible paint that somehow leeches JUST the copper oxide from inside the second coat eh? I reckon that is utter bollox.

My own feeling is that if a house painter arrived every year, announced how you would die if the front door wasn,t painted freshly, then whammed it with a jetwash and said Look! see it,s almost gone, more pêople wd paint front doors, every year.

I have seen new painted local boats in antibes with plenty barnacles after a month, so the chemistry isa lot less important thant the mktg imho.

The 30kilos ole paint not worth worrying about. If it aint worn thru, what the heck, leave it. Its a nice layer of paint that can be jetwashed as requrd.

To stop barnacles growing, mix trilux with copper powder, but gotta be ashull copper powder that makes the tin weigh twice as much (look at periodic table, copper is heavy gear) not just a teensy bit of copper flavouring, u need nearly 1kg per litre, i use .75 kg per litre. Buy the copper powder under 250micron from a craft shop on internet. Before relaunch turn the gear green with any mid acid, vinegar on a sweeping brush, oxalic or weeing on it all work. Looks a mess cos the oxide goes of at diffrent rates, but all sorted after coupla weeks. No barnacles after more than a year. But copper powder is only antibarnacles, not anything else.

Speedwise, i reckon the prop and rudder cleaning gives back upo to half the speed. Clean bum gives back the other half.

Ok, no i dunno the chemistry.
 
You must log in or register to reply here.

Share this page

Top