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Jim Woodall · 21-03-2013, 07:57

I respectfully disagree with minaret's comments:

"All you guys who are saying this is an easy DIY fix are dead wrong. Grinding out some individual blisters and filling them is not a fix. Only peeling, properly drying, and barrier coating will fix this, the rest is just a band-aid. It'll keep coming back and getting worse until its properly repaired or until hydrolysis sets in. Budget about 20k for a proper repair, and have it done right."

What has been described is a DIY job for most people. It is also much more than a band-aid approach. It is a proper repair if done correctly. It will also last the life of the boat in all likelihood. For minor blisters you do not have to peel and grind. If the seller will pay for it by all means grind away. I would properly repair the individual blisters and use the money saved for something else.

**minaret** · 21-03-2013, 08:19

Quote:

Originally Posted by Jim Woodall

I respectfully disagree with minaret's comments:

"All you guys who are saying this is an easy DIY fix are dead wrong. Grinding out some individual blisters and filling them is not a fix. Only peeling, properly drying, and barrier coating will fix this, the rest is just a band-aid. It'll keep coming back and getting worse until its properly repaired or until hydrolysis sets in. Budget about 20k for a proper repair, and have it done right."

What has been described is a DIY job for most people. It is also much more than a band-aid approach. It is a proper repair if done correctly. It will also last the life of the boat in all likelihood. For minor blisters you do not have to peel and grind. If the seller will pay for it by all means grind away. I would properly repair the individual blisters and use the money saved for something else.

We all have our opinions.

I bet I've done more blister repairs than everyone on this forum put together though. How does grinding and filling individual blisters address the root cause of the problem, osmosis? It doesn't, at all. Therefore the problem will continue. In fact, because the filler you have used to replace solid laminate in the blisters is softer and more porous than the laminate, this method actually will make the problem worse over time instead of better. If you plan on owning the boat for five years or less and then selling to a sucker, go for it by all means. But if you actually intend to keep the boat long term and properly care for it, fixing it right is the only logical approach.

Watercolor · 21-03-2013, 10:14

andre - Just a reminder.

It's very possible the surveyor won't know or understand the issue, so here's how it all works.

1. Forespar's Marelon (the material your seacocks are made of - unless they've been changed to bronze) is simply Dupont Zytel nylon 70G13L BK.

2. According to Dupont that material will loose over 60% of it's strength when submersed in water for any reasonable length of time.

3. What nylon does in water is soften and elongate (stretch). Just like nylon rode does. It's great for rode, not so good for rigid items.

4. The four main bolts and the handle bolt are all screwed into the nylon. After months wicking water the nylon threads soften to near mush. In effect, you have nothing more than a soft nylon threaded nut keeping you from a disaster.

5. If the ball is slightly stuck, any off center action can strip the threads and the handle and bolt end up separated from the housing.

6. The Forespar 93 is designed in such (in my mind careless) manner if the ball is not fully closed water will flood the boat.

7. It's all approved, but simply the wrong material for a boat and a very poor design.

I understand your situation. The fact is, like most boat owners, you will never encounter this situation, but many Catalina owners have.

Good luck and fair winds.

N.B. Have you ever thought of getting a boat out of Oz or NZ or the French islands to the south of you?

letsgetsailing3 · 21-03-2013, 13:49

I was under the impression that most older boats have blisters, and that it's not that big a deal -- that you just fix them and move on. It's a regular maintenance issue.

Is that not correct?

Watercolor · 21-03-2013, 14:36

Blisters can be a big deal if not tended to early enough. It's worth checking for blisters when you take the boat out of the water, and if possible, take care of them.

So take care of them and go sailing or boating.
Here's a video by Jamestown Distributors that i thought was informative on blisters.

West System Blister Repair Howto Part I - YouTube

Jim Woodall · 21-03-2013, 15:38

letsgetsailing3,

IMO the answer is yes, blister repair is a regular maintenance issue for most older fiberglass boats. However, with a good maintenance schedule, some attention to detail and proper barrier coating for the entire bottom you will be able to obtain a complete repair. There is no need to peel and apply a new bottom due to minor blistering.

There is a good article in the current issue (April 2013) of Cruising World entitled: Strip Your Bottom Paint (p.54-57)The article will be a good starting place for anyone with minor blistering to their sailboat.

As I mentioned in an earlier post in this thread, I work on blisters each time I haul my boat. I applied a very good barrier coat during my first haulout almost ten years ago and repaired the largest blisters (dime-sized). With each subsequent haulout I've repaired more blisters. Although I still don't have a blister-free bottom, very few if any new blisters have developed since I've owned the boat. Moreover, the existing blisters have not grown significantly. I'm at the point now of repairing very, very small blisters that I could just as easily leave alone with no adverse effects. I'm so close to a blister-free bottom that I plan to continue my routine for one additional haulout at which point I should be finished.

The key is to maintain a really good barrier coat so that new blisters don't develop and existing ones don't get significantly larger. I will apply a new barrier coat this spring. I estimate my costs for blister repair and barrier coating to be no more than $1,200.00 during the entire 10 years I've owned my boat, including the supplies I will use this spring. Most of that expense has been a high quality two-part epoxy barrier coating system. I saw one estimate of $20,000.00 for a properly repaired bottom. That estimate might be reasonable for a seriously blister-damaged bottom, but for minor blistering it can be done properly for much, much less. After my next barrier coat I don't anticipate any additional expense to repair blisters on my boat for at least 8-10 years.

letsgetsailing3 · 21-03-2013, 15:48

Great discussion.

**minaret** · 21-03-2013, 16:33

Quote:

Originally Posted by Jim Woodall

letsgetsailing3,

IMO the answer is yes, blister repair is a regular maintenance issue for most older fiberglass boats. However, with a good maintenance schedule, some attention to detail and proper barrier coating for the entire bottom you will be able to obtain a complete repair. There is no need to peel and apply a new bottom due to minor blistering.

There is a good article in the current issue (April 2013) of Cruising World entitled: Strip Your Bottom Paint (p.54-57)The article will be a good starting place for anyone with minor blistering to their sailboat.

As I mentioned in an earlier post in this thread, I work on blisters each time I haul my boat. I applied a very good barrier coat during my first haulout almost ten years ago and repaired the largest blisters (dime-sized). With each subsequent haulout I've repaired more blisters. Although I still don't have a blister-free bottom, very few if any new blisters have developed since I've owned the boat. Moreover, the existing blisters have not grown significantly. I'm at the point now of repairing very, very small blisters that I could just as easily leave alone with no adverse effects. I'm so close to a blister-free bottom that I plan to continue my routine for one additional haulout at which point I should be finished.

The key is to maintain a really good barrier coat so that new blisters don't develop and existing ones don't get significantly larger. I will apply a new barrier coat this spring. I estimate my costs for blister repair and barrier coating to be no more than $1,200.00 during the entire 10 years I've owned my boat, including the supplies I will use this spring. Most of that expense has been a high quality two-part epoxy barrier coating system. I saw one estimate of $20,000.00 for a properly repaired bottom. That estimate might be reasonable for a seriously blister-damaged bottom, but for minor blistering it can be done properly for much, much less. After my next barrier coat I don't anticipate any additional expense to repair blisters on my boat for at least 8-10 years.

If you do a bit of searching here on this site and elsewhere, you will find multiple accounts from people who have applied a barrier coat to a bottom which was not completely dry, sealing the moisture in, and making the problem worse instead of better. The only way to get a truly dry bottom is to remove the gelcoat. And the most efficient way to do that is with a peeler.

Often with small blisters, the original gelcoat is a big part of the problem and is failing. Coating over a coating which is already failing is a recipe for continued failure. The problem is between the gelcoat and the glass, the gel must be removed to resolve it.

Here's some pics of my bottom being done on this thread-

http://www.cruisersforum.com/forums/...fit-95666.html

**neilpride** · 21-03-2013, 17:07

That hull is wet, grinding and filling individuals blisters is good as a temporary repair and nothing else, until you get rid off of gelcoat, let it dry and barrier coat epoxy your hull is at risk of serious hidrolisys as Mina say, and if the hull get hidro is gone, peeling and laminate is the only option , i dont know if the bottom is cored or not, if yes, peel the gel and do it properly, get a deal with the seller if you are really interested in the boat . Good Luck.

Jim Woodall · 21-03-2013, 17:49

minaret:

I don't disagree with your last post; however, even the presence of many small blisters does not necessarily mean there is osmosis which is so extensive that the hull requires peeling. There are simply too many boats afloat with sound bottoms that have extensive blistering. If blistering is too extensive barrier coating will undoubtedly make the problem worse, but a proper evaluation of the extent of the damage would avoid making it worse. I have specified that I am talking about the repair of minor blistering. Thousands of fiberglass bottoms have been repaired without peeling the bottom. The bottom of my boat is much better now than it was a few years ago and I have seen many similar repairs over the last 30 years with excellent results. I have peeled and then applied 4 new bottoms on boats between 28' - 35'.

I saw your refit thread and read your accompanying comments. You have obviously done a great deal of boat repair/rebuilding in your career. I have been working on boats since I was a teenager, more than 35 years, but not professionally. There are many good methods to get most jobs done, and done very well.

I can appreciate the extensive refit you have undertaken. I spent more than 6 years, and by my best estimate approximately 2000 hours, rebuilding a 70', 1960 Grebe Motor Yacht. It was a wooden boat that we eventually glassed. We rebuilt her stem to stern, wormshoe to antenna tip, and bilge to kingboard. We re-hogtied her and built every piece of furniture inside by hand. She was completely glassed in below the waterline over the course of the long, hot summer of 2006. I will try to post a few photos in the next couple of weeks.

andreshs1 · 21-03-2013, 18:39

watercolor
thanks for the details on the faulty seacocks, I'm printing it out.

minaret, jim et al.

much appreciated your comments on the osmosis, I'm rather new to boats (bought my first one 2 years ago using more heart than brains and I'm still paying for that mistake...)
so this time I am using a surveyor but also seeking 2nd, 3rds and more opinions on the matter.

As you mentioned before, everyone is entitled to their own opinion, for me I prefer to hear as many as possible and draw my conclusions from there and my personal experience.

so thank you all for your inputs

I'll take some pics tomorrow during my visit to the boat to get your opinion

regards
Andres

**minaret** · 21-03-2013, 19:17

Quote:

Originally Posted by Jim Woodall

minaret:

I don't disagree with your last post; however, even the presence of many small blisters does not necessarily mean there is osmosis which is so extensive that the hull requires peeling.

My point was exactly that the presence of many small blisters DOES mean that there is osmosis. How else did water get on the other side of the gelcoat to create the blisters? And if there is osmosis, that means high moisture readings. Since you cannot barrier coat a bottom with high moisture readings without making the problem worse instead of better, and barrier coating is the only proven cure for osmosis, it is clear the peeling and drying is the only actual cure. Without getting further into a subject I have discussed ad nauseum on this forum, I suggest you do a search here and elsewhere on what happens when osmosis becomes hydrolysis. Run high moisture readings in a laminate hull for long enough and it will delaminate on you, there are pics here.

Even way back in the old days when we actually did spot repairs on blisters in the yard, something we no longer do because we hold the industries longest warranty, we never just ground and filled them. We always did a full coatings removal, ground the blisters out and washed them, dried the bottom, and then fiber glassed each blister back up like a repair. This is because we peeled a lot of boats that had obviously been spot repaired repeatedly, with several different products used by different owners filling the blisters clearly visible after the peel. In a number of cases every single recurring blister was in the filler from previous repairs, with none whatsoever in the laminate. Really clear evidence to us that large quantities of filler on a bottom is a terrible idea. I have gone in depth into the reasons why elsewhere on this forum more than once before. Suffice it to say that following the manufacturers instructions to the letter and doing this job efficiently are not compatible.

Thanks for the refit empathy. It's an epic one. About to enter month four of seven days a week twelve hours a day in the yard on this one...

Phil Turner · 22-03-2013, 04:42

Listen to the man in Seattle you guys. To many boat yard lawyers here. Have cut boats with "minor blistering" till you could see daylight. Respectfully Phil Turner

SimonV · 22-03-2013, 05:27

Quote:

Originally Posted by letsgetsailing3

I was under the impression that most older boats have blisters, and that it's not that big a deal -- that you just fix them and move on. It's a regular maintenance issue.

Is that not correct?

Yes, not all but lots. I will be getting stuck into mine next week. I do mine every 2 years and they seem to be getting less and smaller....but I have not looked yet, tell you in 4 days. The last ones where mainly small and just in the gel coat These I dealt with using a burr bit on a drill (very civilized and not too invasive). Every time before I haul out I say to myself this year just paint and re-splash, but I cant help myself and fix what i find.