barrier coating

Sumner · Nov 19, 2011

fiestaMojo said:
has anyone had experience with Sea Hawk barrier coating? the guy who soda-blasted my bottom recommended I use this vs. any other brand; he told me the stuff is so good, one coat is as good as several coats of the competing brands - sounds too good to be true. . .

I used the Tuff Stuff from them on our Mac and will also be using it on the Endeavour in a couple months. I liked it and it does have a higher build film than most of the others. They recommend 2-3 coats. I used 2 and will put 2 on the Endeavour.

Above is with the bottom paint over the Tuff Stuff that was in the first picture and the application is here.....

http://purplesagetradingpost.com/sumner/macgregor2/outside-39.html

I bought from the Bottom Paint Store....

http://www.bottompaintstore.com/tuff-stuff-highbuild-epoxy-primer-by-sea-hawk-paints-p-9473.html

They had a good price and free shipping over a certain purchase price. I used a 2 gallon kit on the 26 foot Mac for 2 coats total. I think I'll need 6-8 gallons total for the Endeavour. It was $120 for 2 gallons when I bought it before, but now it has gone up, like all the rest of the paints.

I don't have long term experience with it, so keep that in mind,

Sum

Our Endeavour 37

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mitiempo · Nov 19, 2011

I don't think you can put a thick enough protective layer on with one coat. You want about 10 mils. Interprotect 2000E calls for 4 - 5 coats to achieve the required thickness.

Sumner · Nov 19, 2011

mitiempo said:
I don't think you can put a thick enough protective layer on with one coat. You want about 10 mils. Interprotect 2000E calls for 4 - 5 coats to achieve the required thickness.

SeaHawk claims 6-7.5 mils dry per coat for the Tuff Stuff and does recommend 2-3 coats and you are right I wouldn't only go with 1 coat. Less coats vs. the Interprotect was one reason I decided to try it. Still Interprotect is probably used on more boats out there than anything else and you can't go wrong with it or Petitt's products either.

With all of these there are requirements for proper application and also for top coating with the bottom paint that also have to be considered. A person wants to stay within the time frame to have propler adhesion between the barrier coat and bottom paint. I'd read the application on all of them and use the one that you can work with the best,

Sum

Our Endeavour 37

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Maine Sail · Nov 19, 2011

fiestaMojo said:
has anyone had experience with Sea Hawk barrier coating? the guy who soda-blasted my bottom recommended I use this vs. any other brand; he told me the stuff is so good, one coat is as good as several coats of the competing brands - sounds too good to be true. . .

Sure it is...

All barrier coats are epoxy based and some are better formulated than others for ease of application, open times and performance. A quick look at what some of the best yards in the country use will reveal that Interlux Interprotect 2000E is by far and away the most widely used and loved barrier coat going. The yard I stored at tried many brands from Pettit, to off brands, and always came back to IP2KE.. Top quality builders like Morris, Lyman Morse & Hinckley also choose IP2kE..

I would ask your guy what data he has to back up the claim that one coat will suffice. With epoxy barrier coats it is all about dry film thickness....

All that said your substrate must be DRY before applying any barrier coat or you've wasted your money and sealed moisture into your hull.. It can take months for a hull to properly dry and a moisture meter should be sued to confirm laminate moisture levels..

You should also check with the manufacturer about "hot coating" windows..

Sumner · Nov 19, 2011

fiestaMojo said:
.. he told me the stuff is so good, one coat is as good as several coats of the competing brands - sounds too good to be true. . .

I was reading this at first to say that he said you only needed one coat, but on re-read I think he is just saying that one coat of the Tuff Stuff has the same build in film thickness as a couple coats of other bottom paint. That does seem to be the case. The Sea Hawk is about 6-7 mils dry build and from what I find the Interlux is about 2.5-3.0 mils dry build per coat.

If all of that is correct it would take a couple coats of the Interlux to equal one coat of Sea Hawk. The Interlux does cover more sq. ft. per gallon, so it is about a wash as far as how much paint you use. Ask him how many actual coats he recommends and the minimum build and see if it matches up with the 10 mil.

It mainly comes down to your preference on if you think they will both get the job done the same and if putting on more coats time wise will work for you. Obviously the safe way out is to use the Interlux as it is the favorite as MS pointed out. If we end up with blisters in the future I'll be pointing that out. It won't be a good test though as we probably won't ever have the Endeavour in the water for more than 5-6 months out of the year while we own her,

Sum

Our Endeavour 37

Our Trips to Utah, Idaho, Canada, Florida

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Prime Time · Nov 19, 2011

I used the west system epoxy on my old boat, a mirage 27. I did it with my kids. Completed in one long day. Coats applied while under layer still tacky. About 8 coats which was probably overkill. Used a uv inhibitor for final coat. Then primer before petite ultimate sr bottom paint. 4 yrs and the boat has no blisters reforming.

Joe · Nov 20, 2011

12 years ago I hauled my boat, opened at least 50 blisters, let them dry for ONE day, repaired with 3M blister kit...... spot covered the repairs with 2-part ProLine epoxy primer, then a couple of coats of west marine modified epoxy bottom paint. 2 years later, hauled out again, paint was wearing off, but no new blisters, so I paid my diver $200 to clean the bottom and apply 3 coats of an unknown bottom paint he said was good. That paint lasted NINE years.... with a diver cleaning it once a month. I hauled out again in 2010.... NO NEW BLISTERS!

My boat is a 1977 catalina 27 and has always been stored in the water. Never had a complete barrier coat. So why haven't I had any more blister problems.

mitiempo · Nov 20, 2011

Luck?

Sumner · Nov 20, 2011

Joe said:
12 years ago I hauled my boat, opened at least 50 blisters, let them dry for ONE day, repaired with 3M blister kit...... spot covered the repairs with 2-part ProLine epoxy primer, then a couple of coats of west marine modified epoxy bottom paint. 2 years later, hauled out again, paint was wearing off, but no new blisters, so I paid my diver $200 to clean the bottom and apply 3 coats of an unknown bottom paint he said was good. That paint lasted NINE years.... with a diver cleaning it once a month. I hauled out again in 2010.... NO NEW BLISTERS!

My boat is a 1977 catalina 27 and has always been stored in the water. Never had a complete barrier coat. So why haven't I had any more blister problems.

I might have to agree with....

mitiempo said:
Luck?

The other thing is that sometimes two identical boats don't seem to both get them. Someone who really knows more might be able to comment better, but it seems that I've read that it has something to do with the quality of the product going on the boat when it was made. I know some guys with Macs complain that their boat develops them fairly quickly and others with the same model that slip their boat don't get them. Our Mac didn't have any, but I don't know if it was ever in the water for an extended time. I did know I wanted to put bottom paint on before going to Florida and decided that it would be way easier to put a barrier coat on then vs. later.

I made a bad assumption when we bought the Endeavour. Blisters had been repaired in 2006 on it and I assumed that since the report said a barrier coat had been applied in the bill I saw I figured that the whole bottom had been barrier coated. We bought the boat without having it hauled out. When we did haul it out to store it before returning home we were blessed with 40-50 new blisters on the bottom, most small. I could see that they had only barrier coated the blisters they repaired in 2006 and that hadn't stopped new ones from forming other places.

So now instead of just putting on bottom paint we had to have the old paint removed, the blisters repaired and I'll re-paint, barrier and bottom, when we go back. This has been a few thousand that we didn't think we were going to have to spend. If the boat would of been at home I would of done all of the repair. This is about the first thing I've ever hired out in my life :cry:. The boat was hauled late May and 90% of the blisters are repaired, but they are still waiting on 3 to finish draining and drying, so MS is correct that it can take some time if you don't want to take the chance on trapping moisture.

So I guess you were either lucky or more blisters just weren't going to form. Either way sounds like you are in good shape

,

Sum

Our Endeavour 37

Our Trips to Utah, Idaho, Canada, Florida

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mitiempo · Nov 20, 2011

Even without blisters it takes a long time for a hull to dry out.

Squidd · Nov 20, 2011

I have my boat on the hard at home and it needs a bottom "job"..

Temperature and weather wise I don't think I'll have a decent warm enough spell to paint till next spring..

So it sounds like I should sand, strip and peel my bottom open so it dries over the winter...? and deal with application in the spring...?

Joe · Nov 21, 2011

The "legend" that I have always been aware of, concerning blisters, is two part:

First, that there was an era of boatbuilding in so cal where the many production facilities used inferior batches of resin/fiberglass, a direct result of the petroleum wars of the late 70's and early 80's. And......

Second, for boats produced in this era, there is "window" of time in which blisters are more likely to blossom ... say between 15 to 25 years of the boat's life.

Does this sound familiar, or make sense, to anyone?

Prime Time · Nov 22, 2011

Blisters

I've read a bunch about blisters and done a bottom job. Osmosis is the real culprit and what seems clear is that nothing is always clear or predictable
But:
Gelcoat is porous.
There did seem to be an increase in Blisters during the era you described.
Some boats have "wet" hulls by a moisture meter yet have no blisters.
Other boats have blisters between the outer laminate and gelcoat
Some boats have blisters inside the outer laminate, and this type of a problem can be structural.