Jump to content

Antifouling


Whiting 34

Recommended Posts

yes you still have to wipe or scrub every few months

 

 

 

 

 

I hear this comment often, but I don't get that. Why not have a bare Hull and scrub that every few months.

Anyway, the recommendation is to sand the surface yearly to expose fresh copper.

 

 

 

 

we were up the tamaki river near the bridge where all the boats had slime within a month,and the local chandlery guy said you would need to wipe monthly to stay clean even with fresh antifoul, it wiped off the coppercoat easily with no barnacles,nothing like a bare hull , we have had barnacles on a bare hull trailer sailer within 2 weeks, even when sailing daily. obviously location makes a huge difference , when we left gulf harbour with a slime covered boat it literally fell off leaving a trail of slime as we moved away at only around 3 knots, the tamaki slime hangs on at 15 knots and more. a couple of launchs in new plymouth have had great results with coppercoat, one for over 10 years with only an annual scrub/light sand.

seems all antifoul on boats that are not used daily need some regular cleaning if you want to stay efficient, and every time you wipe a soft antifoul you are losing more of your coating. you know what they say you pays your money and you takes your choice just pick your poison.

 

Contrary to the understanding of many, pure copper does not stop fouling growth. If you put a sheet of copper into water, it will foul up just the same as any other material you put in the water. But they used it on the old Ships you say?? yes correct. But interestingly, they also had electrolysis issues that caused the copper sheet to deplete. So one smart fellow said, why don't we put anodes on the Hull and stop the Copper wearing away. Suddenly growth appeared on the Hull and in 6 months, they had to clean the Hull, remove the anodes and allow the Copper sheet to wear away again. The fact was, the copper eroding caused a small amount of copper Ions on the surface, which was the actual stuff that stopped the growth. Hence why Copper based Antifouls have Copper oxide in it, not pure Copper.

probably it is copper oxide that is in coppercoat it is a dark brown soft but heavy powder that is mixed with water soluble epoxy resin and applied in about 7 coats wet on tacky in one day.the whole process with preparation took around a week. i like it but with my boat for sale have recoated in standard antifoul, if i ever get a boat i think i will keep for 10 years i would use it :D

Link to post
Share on other sites
Sailor x, any ideas / recommendations re antifoul for alluminium application?

 

 

Hi Steve, this is a good question.

 

In NZ The usual Products like Altex's Vivid and Internationals Trilux are safe but very average performers.

 

The other option I know of is Trilux® 33 from Interlux. This is a copper based paint but it is copper thiocyanate, which Interlux say is safe for properly barrier coated aluminum boats.

 

The term " barrier Coated" is to use a 300 micron coat/ film (dry) of good quality epoxy primer (for underwater) between the Antifoul and the alloy.

 

The correct system would be to clean the Alloy back then 2 pack etch the alloy followed by a good 2-3 coats of epoxy primer. then antifoul.

 

The alloy has to be 100% encapsulated.

 

There are some interesting commercial systems that allow the use of normal Cuprous (Cu2O) oxide antifouls. These system involve application of a Specialized epoxies containing a Zinc derivative and are very successful.

 

I think Altex Coatings in NZ has used this system in the past with great success.

 

By far the best is the silicon rubber (this is interesting link - http://www.google.com/patents/US3702778) products as used on the ferries that travel the worlds harbours. i think your smaller Fullers ferries have this on?

 

These require constant movement but for legs is great and lasts for years if done properly.

 

also of interest is this commercial product.

 

Intercept®

Intercept® is a brand new patented biocidal antifouling that will revolutionise predictability in

hull coating performance.

 

Intercept®8000 LPP

Featuring brand new patented Lubyon® polymer technology, Intercept®8000 LPP

provides consistent, predictable linear polishing performance.

docking cycle, for in-service periods of up to 90 months.

 

hope this helps?

 

Oh... forgot to mention.

 

the link above shows some very interesting references for this product.

 

I was involved in the early developmental testing of Silicone technology for A/fouls and this was the forerunner to all the new products on the market today.

 

Dow chemicals had a breakthrough in the 70's with Silicone and then Courtaulds (International) made it work. It took ten years testing to prove this technology with many immersion tests around the world before it was commercially launched to the shipping fleets.

 

Propspeed is similar technology and is based around a modified "non Acid" Urethane silicone.

Link to post
Share on other sites

Thanks, Sailor X. I have used both Trilux and Trilux 33, the only noticeable difference was the price and the 33 slimed up faster than the std trilux, probably from lack of speed through the water. I am currently using a Hempel product, but I haven't been sailing for quite a while (TKR) so I have yet to see if it is an improvement.

Link to post
Share on other sites

Our experience with coppercoat after 18 months is that it slimes up quickly (2 months in Bayswater), but wipes of easily and suffers little hard growth.

 

We generally dive to clean the bottom. As we dont need to haul this is a good solution for us.

Link to post
Share on other sites

Any and every anti-foul coating slimes up. Well....all except one, being the Micron 66 and I assume the Micron extra. Micron being an antifoul that is self polishing or erroding or sloughing or whatever you want to call it. Micron works by the surface continually reacting with the water and falling away taking Slime with it. But it last 12mths only and is very expensive. But if you want a continuous clean hull even when sitting in the Marina, it's the only one. All other Antifouls must either have water flow over the Hull to erode the surface, taking the slime with it, or a wipe with a brush/sponge to keep the surface clean.

Link to post
Share on other sites

as someone stated the panmure river is a shocker.

i am moored below pybc near main channel,strong currant and you can clean/antifoul with what ever brand or type you like and in 2 weeks slime.unless slime is removed this creates are a bed for the next growth weed,then barnicle attach.

must be the worst area in ak that i have ever moored in.wonder is there to much industrial pollution entering river?

side line,was copper sheeting on sailing ships to stop the worm?

Link to post
Share on other sites

panmure river,according to sum log the boat travels 8 miles a week,with that sort of currant it amazing how the stuff sticks.every months gets a good broom off and never any anti foul falls off so unsure whats on bottom,previous owner cannot remember either.starting to think it could be coppercoat

Link to post
Share on other sites

In rivers and estuary's there are two main contaminants.

 

Slime (similar to a algae blooms)

 

Mud (similar to mud)

 

Most of the fouling you will be seeing is mud.

 

Why? Well because it is always in the water and mainly in Fresh or fresh salt water mixes.

 

Slime will be present in warmer waters and almost non existant in cool water.

 

Some AF's have "anti slime " boosters. Slime is an issues and hard to combat. There is some development work happening with "active surface/film technology. The plan is to make the AF very active that Even slime erodes off the AF.

 

If you .book at nature you will see that moving object like fish do not foul. This is because the are moving and their skin is highly active/and has a film that is active (slimey)

 

But also some crustaceans also never foul yet they have hard shell skins and move slowly. These fish have unique compound in their shell that are natural AF's

 

Chemists are working on this and super smooth technologies.

Link to post
Share on other sites

the stuff that sticks to my hull in the tamaki river seems to be connected to the small shrimp like wrigglers that are on the hull, you can go around the boat and wipe them and the stuff off and half an hour later some of them have swum back and started putting stuff back on the hull, it seems that they produce it and stick it there? need some hungry fish to take them out :idea:

Link to post
Share on other sites

sorry don,t have any photos but they look like mini prawns with a tail head and legs ,one would fit on your little finger nail, when you get out after scrubbing the boat they are all over you, wriggling,clear greyish colour, will see if i can find a photo on google

Link to post
Share on other sites

they look like this but dark grey/translucent around 10 to 15mm long, maybe like krill, perhaps they like the freshwater/salt mix that we get up by the bridge, might have to bring in some whales from down south to do a contract on them. :)

akcp-krill-portrait-585mfk011011.jpg

Link to post
Share on other sites

hard to believe what grows on hulls in the tamiki river,i am down towards 2nd last green marker from pybc and at times according to sum log the boat travelled 6 miles in a week and not leave the mooring,as previous scrub and next day there is signs of slime,

Link to post
Share on other sites

I have seen the same shrimpy little sh*ts on our boat (Little Bucks) and have been very piss*d off to see $200plus in anti foul can do nothing to stop the slime.

As far as fish to eat the stuff off, when we go into 1/2 Moon Bay Marina, the parores are almost cuing up to get a bite but it would take a month for them to even make a mark!

Are straddle crane drivers growing prawns to create more business?? :twisted:

Link to post
Share on other sites

Typically krill are a temporary issue.

 

Questions...

 

To the people suffering with this krill.

 

1. What Anti foul are you using?

 

2. What is the water temp?

 

3. Is this an usual problem or just a one off issue this season?

 

Krill are algae eaters and algae usually only blooms for a short while.

 

They are either using your hull as a hotel or a restaurant (epibiosis).

It would be interesting to learn if other boats in your area are the same or just certain type (antifouling)

Link to post
Share on other sites
Typically krill are a temporary issue.

 

Questions...

 

To the people suffering with this krill.

 

1. What Anti foul are you using? warpaint, altex, coppercoat, international, all have same results. maybe one soft ablative i used was a little better but when we wiped it you would lose so much paint.

 

2. What is the water temp? varies winter and summer perhaps 12 to 21 c?

 

3. Is this an usual problem or just a one off issue this season?

usual problem

Krill are algae eaters and algae usually only blooms for a short while.

 

They are either using your hull as a hotel or a restaurant (epibiosis). maybe a hotel

It would be interesting to learn if other boats in your area are the same or just certain type (antifouling)

I have answered above they seem to be on all the boats around us, the mud type deposit they put on the hull is also on the mooring lines and they will be very dirty even after only a week in the water. wipes off easily when wet. harder to remove if allowed to dry.
Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...