Barrier coat, do you use them? Why?

[Recoil Rob]

2004 180 Sportsman, new to me, never been bottom painted. Will be slipping it this summer in Norwalk, CT.

Bottom looks clean now, no blisters. I have been getting differing advice as to whether to barrier coat or not.

A friend owns a marina in RI, says don't bother. Another local marina says the same. Pettit says do it, but they want to sell paint.

I can afford to do it (will be doing it myself) but is it necessary? What did you do? What do dealers do?

I suppose it's one of those things that you'll only know if you didn't do it and got blisters.

Anyway, opinions?

 

[SkunkBoat]

DO IT.
Polyester gelcoat can absorb water... leading to blisters.
I am surprised you have marinas saying don't worry.

 

[Recoil Rob]

That's why I am asking here.
...

 

[DennisG01]

I had always heard that you really didn't need to worry about it with a Grady as the process of applying the glass to gelcoat has as much to do with it as the formulation (poly, vinyl, etc). I actually called the factory a number of years ago and asked about this - when my '82 was "new to me" - and they told me point blank not to worry about doing a barrier coat.

I just now did some googling to find out some more and found this article, where a GW manager talks about it and says “If you do your gelcoat right and your gelcoat is compatible with your resins, you won’t have blistering problems."

Here's the article: https://www.soundingsonline.com/news/grady-white-what-goes-into-a-grady

That said, it certainly can't HURT to barrier coat it. But in my opinion, with what I've learned, it just isn't necessary.

 

[drbatts]

I raised the waterline a couple of inches on my boat after I bought it. The bottom was/is painted with pettit hydrocoat and as far as I can tell here is no barrier coat underneath. I used petit bio blue surface prep on the bare surface and then painted with hydrocoat as per their directions. I thought about barrier coating but this was just easier.

 

[seasick]

If your hull is 2004 and has been used recently (not stored on land for years) AND you don't see any blisters, you don't need barrier paint at this time. The reason I mention about the boat being used recently is that some blisters can shrink kind of quickly as the hull dries out.

 

[Fishtales]

I had always heard that you really didn't need to worry about it with a Grady as the process of applying the glass to gelcoat has as much to do with it as the formulation (poly, vinyl, etc). I actually called the factory a number of years ago and asked about this - when my '82 was "new to me" - and they told me point blank not to worry about doing a barrier coat.

I just now did some googling to find out some more and found this article, where a GW manager talks about it and says “If you do your gelcoat right and your gelcoat is compatible with your resins, you won’t have blistering problems."

Here's the article: https://www.soundingsonline.com/news/grady-white-what-goes-into-a-grady

That said, it certainly can't HURT to barrier coat it. But in my opinion, with what I've learned, it just isn't necessary.

This will be a religious battle for some. I'm in the camp with Dennis on this one. GW has not had a blistering prob since the 1980s and learned the hard way to control their resins and gelcoat.
You can do it to a virgin hull, lightly sand to prep. It won't hurt and could help. If you have the jing and/or the time, do it. If not, you can direct paint with an ablative paint and you will be good. I'd probably do it on a factory fresh boat, but if the boat was in the water previously I'm guessing if you were going to have a problem, you'd have it by now. Just one guys opinion.

 

[SkunkBoat]

no glove, no love.....

 

[usmm1234]

I’ve been in the boat business for 42 years. I’ve co owned 2 dealerships. I wouldnt put a boat in the water long term without a barrier coat under any circumstance. My 33 Bertram was loaded with blisters and they used the finest gel coat on the planet.. I have seen many boats of every brand with blisters. The barrier coat is also a primer and gives a proper surface to adhere to. I just soda blasted, primed and painted my Grady. I used the Pettit 2 part white epoxy barrier primer coat and Pettit Vivid paint. I used the Vivid because I had planned to keep the boat in dry storage. Pettit has some better paints for keeping the boat in the water.

 

[seasick]

I see your point but in the case of a 16 year old hull without a history of blisters, there really is no need now to barrier coat. If he wants to, that's not an issue except that he will have to strip the hull especially if it had ablative paint in the past. In my opinion, a lot of cost for not much return.

 

[usmm1234]

I see your point but in the case of a 16 year old hull without a history of blisters, there really is no need now to barrier coat. If he wants to, that's not an issue except that he will have to strip the hull especially if it had ablative paint in the past. In my opinion, a lot of cost for not much return.

If the boat has bottom paint on it now. It almost surely has a primer/basecoat on it. I have never heard of any reputable dealer or yard applying Bottom paint without a barrier coat. That would actually liable the yard down the road unless the customer specified "no primer". As I said as a certified marine surveyor and decades of professional service in marine. I would Not apply antifouling paint without a barrier coat.

 

[seasick]

Primers yes, but barrier coats, maybe not the norm.

 

[DennisG01]

I agree that it's quite normal to have just bottom paint (using either a self etching primer or physical sanding) on it. And, I don't see how there would be any liability on the marina's behalf. After all, the customer is only hiring them for anti-fouling protection. Just for reference, another brand that does well without it is Sea Ray - I know of, literally, 1,000's of Sea Rays that only have regular bottom paint put on and no blisters. Again, certainly can't hurt to use it, and ANY boat "could" get blisters, but in many cases it's just not needed.

 

[Lsquared]

I have a few blisters on mine just above the bottomw coat glad i moved the boat out of the water and back on trailer. Barrier coat it imho

 

[usmm1234]

Absolutely not. Epoxy primers are the norm. Any reputiable yard or dealership is going to put a barrier coat/primer on a bare fiberglass hull before he applies antifouling paint on a boat that is going to be kept in the water. Unless, as I said. Some owner specifies not to use it. I know most of the Interlux and Pettit Reps. I'll be happy to give you a number. Call any Grady , Whaler, Regulator Dealer. They will all tell you to put a 2 part base on. You can get substancial water absorbtion and weight gain without getting visable blisters.

 

[DennisG01]

Absolutely not.

Certainly not something I want to get in an argument over, especially when something like this is opinion based. Maybe it's "the norm" in your area, but it definitely is not the norm everywhere. I'm in the business, as well, and I can tell you that from Maine to the Chesapeake NOT using it is the norm. I can also tell you from the many years I've been on a Sea Ray forum (a HUGE, worldwide forum), that it is also very much the rarity to have a barrier coat.

But again, not something I'd argue over. We each are entitled to our own opinions.

 

[usmm1234]

I’ve been calling on a Sea Ray for 30 years. I sold them all their water pumps and Seacocks for 16 years. We still do the bigger boats. I’ll make a call on Monday to their Enginnering Dept and find out. I have seen many older a Searay’s with Blisters. I have no idea who put the bottom paint on? Especially in fresh water. I just saw a 1989 flybridge 39 Searay on the hill that had about 1000 quarter size blisters.
As far as liability. having co owned and managed 2 dealerships. I can tell you. Customers look to us Marine Professionals to properly advise them on important procedures like bottom coating. An Orthopedic Surgeon has more important things on his mind then how to safely paint his bottom.

 

[usmm1234]

Certainly not something I want to get in an argument over, especially when something like this is opinion based. Maybe it's "the norm" in your area, but it definitely is not the norm everywhere. I'm in the business, as well, and I can tell you that from Maine to the Chesapeake NOT using it is the norm. I can also tell you from the many years I've been on a Sea Ray forum (a HUGE, worldwide forum), that it is also very much the rarity to have a barrier coat.

But again, not something I'd argue over. We each are entitled to our own opinions.

I just emailed Keith Warren at Back Cove Yachts in ME. He’s head of engineering there. I just finished selling them the Glendinning power shore power cable system for their new 390. They also build Sabre Yachts in ME. . I’ll post their bottom prep procedure when he responds.

 

[usmm1234]

Certainly not something I want to get in an argument over, especially when something like this is opinion based. Maybe it's "the norm" in your area, but it definitely is not the norm everywhere. I'm in the business, as well, and I can tell you that from Maine to the Chesapeake NOT using it is the norm. I can also tell you from the many years I've been on a Sea Ray forum (a HUGE, worldwide forum), that it is also very much the rarity to have a barrier coat.

But again, not something I'd argue over. We each are entitled to our own opinions.

I agree. I don’t want to argue over boat bottoms, but there is a certain responability to posting statements or advise on these blogs. There are people that are new to boat ownership that take these blogs as gospel. Have you have checked the price of a new a Grady White these days. We went to a Grady White Dealer open house recently. Your dealing in hundreds of thousands of dollars. You don’t want to tell a guy with a new 30 footer an incorrect process of painting his bottom. The remark that the Pettit guy is just trying to sell paint is fool hardy. My boat is 18yrs old, but I am still adamant about doing it correctly. I have a lot of money by my standards and work invested in it. My father was an avid fisherman (Grady Owner) and sailor. He taught us to never take a shortcut when it comes to working on a boat. It’s the only thing between you and the bottom.
I find that a lot of bloggers will do something incorrectly on their boat because of cost or lack of knowledge. And then advise others to do the same. That’s bad for the boating community.
Ive gotten some great advise on this blog, and I hope I’ve posted some good info for other owners. You will see on my posts. I usually accompany them with pictures of the project. If I don’t know how to do something. The first place I go is the manufacturer’s website.
As far as the bottoms. I’m sure gel coats have made big advances since I was running a dealership. Maybe they don’t seal them anymore. I will post my findings next week. I’ve emailed Grady engineering along with several others.

 

[DennisG01]

Since Sea Ray has gone to vinylester resins, blisters have been virtually non-existant - which may have been sometime in the early 90's, I think. I work at a Sea Ray dealership and can tell you from my experience there, along with that from the Sea Ray forum -where there are plenty of guys much smarter than me - that it just doesn't happen anymore.

But as noted, it's not just about the compostion but the layup process. Up above, I mentioned I called Grady directly and they flat out told me not to worry about doing an epoxy coat. I was totally thinking of doing it based on the year of the boat. But based on what they said and the fact that there currently weren't any that I could find, I didn't bother. All has been well since and that was 5 or 6 years ago. I do think, though, that as time goes on that manufacturers will start to CYA and just recommend barrier coating as a course of business... even though it's not really necessary.

Back Cove... very nice boats (and Sabre). Right in my backyard up there - we have cottages in Friendship and Cushing - just a few minutes from Rockland.

Edit: I should mention that I work at a Sea Ray dealership... one of the oldest in the world, by the way! And I have honestly NEVER seen an issue with blistering on any of the boats we have done.