Bottom paint selection

sailman

Super Anarchist
8,372
480
Portsmouth, RI
I currently have two coats a water based Petit paint over Bottom Cote Epoxy on now and I want to switch to an abalative. Interlux has never really impressed me since they were forced to give up Micron 33. I am looking at Petit Ultima 60 and Aquagard.

Anyone have any reports either way on how these or any other paints are for two seasons in the water on a cruiser located in the North East?

Are the West Marine brand paints worth anything or does the price speak for its quality?

Thanks.

Will Museler

 
Great topic. I'm all ears, because I'm ready to take mine down to nothin' and start all over. I've been reading a bunch of stuff, but still can't decide.

Ready for advice! :)

 

Pertinacious Tom

Importunate Member
63,985
2,204
Punta Gorda FL
OK, here's an excerpt from a not-ready-for-prime-time website I'm working on. I'm no expert, and there may be mistakes. Corrections appreciated.

The older ablative paints were made to wear away through friction as the boat moved through the water, and some of these paints are still available today, such as Interlux Bottomkote ACT and XXX. The problem with these paints is that water wears the paint away much more quickly in areas of high friction, such as the leading edge of the keel and waterline, leaving those areas exposed while there is still plenty of good paint on the rest of the hull.
Modern ablative paints with water soluble or self-polishing copolymers dissolve at a predictable rate, and are not as susceptible to friction wear so tend to wear more evenly and last longer. Paints such as Pettit Ultima and Interlux Micron 66, Micron Extra and Micron CSC, as well as Awlgrip Awlstar, Seahawk Cukote, Super Shipbottom, paints by SeaJet and others fall into this category of more advanced ablative type paints. Pettit's Vivid is a special case, and has characteristics of both ablative and hard paints. The copper thiocyanate biocide and zinc slime-inducers do dissolve away like an ablative bottom paint, but they leave behind the Vivid paint, as happens with a vinyl or epoxy antifouling coating.

Hard Bottom Paints

Hard bottom paints like Pettit Trinidad SR and Unepoxy, Interlux Ultra and Fiberglass Bottomkote, Seahawk Sharkskin and Tropikote and others are durable and can be made very smooth. It is possible to achieve and maintain a smoother finish with these bottom paints than with most ablative types and the paint is long-lasting.

The downsides of the hard paints are that many lose effectiveness when out of the water, and the paint will build up over time if not sanded down each time the boat is bottom painted. Also, hard paints are at their most effective immediately after launching, and are less toxic to marine growth over time as the poisons within leach out. That means that after a year or so, a hard bottom is likely to need more scrubbing than an ablative bottom, which will still just need a light wipe to expose fresh paint with copper biocide.
 
OK, here's an excerpt from a not-ready-for-prime-time website I'm working on. I'm no expert, and there may be mistakes. Corrections appreciated.
The older ablative paints were made to wear away through friction as the boat moved through the water, and some of these paints are still available today, such as Interlux Bottomkote ACT and XXX. The problem with these paints is that water wears the paint away much more quickly in areas of high friction, such as the leading edge of the keel and waterline, leaving those areas exposed while there is still plenty of good paint on the rest of the hull.
Modern ablative paints with water soluble or self-polishing copolymers dissolve at a predictable rate, and are not as susceptible to friction wear so tend to wear more evenly and last longer. Paints such as Pettit Ultima and Interlux Micron 66, Micron Extra and Micron CSC, as well as Awlgrip Awlstar, Seahawk Cukote, Super Shipbottom, paints by SeaJet and others fall into this category of more advanced ablative type paints. Pettit's Vivid is a special case, and has characteristics of both ablative and hard paints. The copper thiocyanate biocide and zinc slime-inducers do dissolve away like an ablative bottom paint, but they leave behind the Vivid paint, as happens with a vinyl or epoxy antifouling coating.

Hard Bottom Paints

Hard bottom paints like Pettit Trinidad SR and Unepoxy, Interlux Ultra and Fiberglass Bottomkote, Seahawk Sharkskin and Tropikote and others are durable and can be made very smooth. It is possible to achieve and maintain a smoother finish with these bottom paints than with most ablative types and the paint is long-lasting.

The downsides of the hard paints are that many lose effectiveness when out of the water, and the paint will build up over time if not sanded down each time the boat is bottom painted. Also, hard paints are at their most effective immediately after launching, and are less toxic to marine growth over time as the poisons within leach out. That means that after a year or so, a hard bottom is likely to need more scrubbing than an ablative bottom, which will still just need a light wipe to expose fresh paint with copper biocide.
The term "sloughing" used to be applied - I think - to paints which came off by themselves layer-by-layer by travel through the water at true-displacement speeds - as opposed to only when you brushed at them - but perhaps I have that backwards.

 

creedence623

New member
17
0
Tampa Bay
I used West Marine's PCA Gold on my boat in Hawaii with no issues whatsoever. I used 2 coats of blue over a red base coat to let me know when it was time for another haulout. Completely satisfied with it.

 
We've tried 'em all, and although we're wood, Trinidad SR modified epoxy does keep the critters at bay...a footnote is that over the years we've noticed that barnacles seem to favor the taste of our seam caulking whenever we deviate away from good modified epoxies. We used West one year on the Great Lakes, but it didn't hold up well....So, spend the frogskins on the spendy stuff, as it's worth it...I notice above in some long explanation that the harder epoxies loose their ability over time...B*llsh*t!!.........Boocoo sea miles under our keel. All the harder epoxie need is a little roughing up to trigger the chemicals when they dry out...From hanging out with the shrimpers when we make obscure ports, the old fashioned idea of adding a can ofcayenne to each gallon does make a difference...

 
Last edited by a moderator:

svbravo

New member
10
0
Boat moored in Seattle.

I'm currently near the end of my second season w/ a 2 coat application of Blue Water Copper Pro SCX 67. I've been very impressed with it's performance. I think the 67% copper is doing the trick. So much copper that the black paint had a slight brownish look when it first went on.

When I haul out this spring, I'm planning on using the same. This after being a long time Interlux (Micron) user. I never really got a full 2 seasons w/ the Micron, but have been surprised to get it from the Blue Water. I hadn't heard about it before, but the yard where I hauled out was offering a promotional special. Good deal all around.

Will be heading to tropics at end of this year, so am hoping the Copper Pro works as well in warm waters as it does in PNW.

YMMV

Adam

 
I currently have two coats a water based Petit paint over Bottom Cote Epoxy on now and I want to switch to an abalative. Interlux has never really impressed me since they were forced to give up Micron 33. I am looking at Petit Ultima 60 and Aquagard.
Anyone have any reports either way on how these or any other paints are for two seasons in the water on a cruiser located in the North East?

Are the West Marine brand paints worth anything or does the price speak for its quality?

Thanks.

Will Museler
when the boat is in the water, there is no early season, its full time. Good luck and have fun

 

Pertinacious Tom

Importunate Member
63,985
2,204
Punta Gorda FL
I notice above in some long explanation that the harder epoxies loose their ability over time...B*llsh*t!!.........Boocoo sea miles under our keel. All the harder epoxie need is a little roughing up to trigger the chemicals when they dry out...
Maybe I should have worded that differently. The point was that the poison slowly leaches out of hard paints, leaving inert paint behind. Toward the end of the life of a hard paint coating, there is not much poison left any more, compared to the end of the life of an ablative paint, where even the last bit is full strength with poison when exposed.

 

sailman

Super Anarchist
8,372
480
Portsmouth, RI
Boat moored in Seattle.
I'm currently near the end of my second season w/ a 2 coat application of Blue Water Copper Pro SCX 67. I've been very impressed with it's performance. I think the 67% copper is doing the trick. So much copper that the black paint had a slight brownish look when it first went on.

When I haul out this spring, I'm planning on using the same. This after being a long time Interlux (Micron) user. I never really got a full 2 seasons w/ the Micron, but have been surprised to get it from the Blue Water. I hadn't heard about it before, but the yard where I hauled out was offering a promotional special. Good deal all around.

Will be heading to tropics at end of this year, so am hoping the Copper Pro works as well in warm waters as it does in PNW.

YMMV

Adam
Sounds good. Big price swing on that paint $219 - $159 per gallon.

 

jimbojones

Anarchist
boat moored in southern new england like yours. using the cheap stuff, petit ssa. I am confident that in S. NE it would go 2 seasons no problem. I have only had light slime no hard fouling and I only did touch up painting last season rather than the whole hull because there was still plenty on it. worked great.

 

Innocent Bystander

Super Anarchist
11,749
759
Lower Southern MD
I have a preference for Micron Extra but it really does come down to local conditions. In the Chesapeake, water temps vary from the low 30's if you "winter in" to about 90 during the heat of the summer. Bio load and dissolved oxygen varies widely.

Buying the "good stuff" is a given as the cost of the paint is a marginal cost of the bottom job. Talk to folks in your home waters - preferably in your marina to see what's working best locally.

When I lived in the NW, we had cold water but a lot of scummy growth in the summer. The creek leading into the marina drained a developed housing area and the nitrogen load from fertilizer gave us a nutrient rich bath to grow stuff in. Paint that worked great a few miles away struggled in our marina.

IB

 

Not My Real Name

Not Actually Me
43,188
2,914
I currently have two coats a water based Petit paint over Bottom Cote Epoxy on now and I want to switch to an abalative. Interlux has never really impressed me since they were forced to give up Micron 33. I am looking at Petit Ultima 60 and Aquagard.
Anyone have any reports either way on how these or any other paints are for two seasons in the water on a cruiser located in the North East?

Are the West Marine brand paints worth anything or does the price speak for its quality?

Thanks.

Will Museler
Evenstar has Petit Ultima SR. So far so good, we paint every other year and it holds off the worst of it.

The only downside I see to it is that when I wanted to switch to something harder like Micron CSC I couldn't without stripping off the Petit. It would not have been my first choice for paints since it is pretty soft (brush the bottom and your clothes are blue forever), but it was painted initially in Florida and apparently that is a better paint for that area.

 
We put on Interlux Micron Extra about 6 months ago and the diver says it is still clean enough not to need cleaning.
Sounds like you found a pretty honest diver!
Or one who maybe doesn't know enough about anti fouling paint. You should never let your paint get fouler than can be cleaned with the absolute softest scrubber in the diver's arsenal. Frequent, gentle cleanings will help your paint last far longer than less-frequent, more abrasive cleanings. If your diver is going to let the bottom get dirty enough that the paint is hidden beneath the slime, he has waited too long and is doing you a disservice. Not saying this is the case here. But most anti fouling paint's copper release peaks at about 90 days after splashing, then tails off to a consistant level for the remaing lifespan of the paint (which is why the manufacturers recommend not cleaning for 90 days after painting). It would be a rare anti fouling paint that didn't need cleaning after being in the water for 6 months in the Estuary. Especially on a cruising boat.

 
Top