Have you exposed your gel coat?

[PSR]

I'm interested in whether you have ever seen the gel coat below the water line on your boat, and whether you have done repairs on the gel coat. Here's the background (I started this in another thread in the medium sized boat forum, but this seems like a place more will see).

My C-27 was built in 1980 (1981 model). She's new to me, and she needed some cosmetic attention to spider cracks in the cockpit. Through a series of steps, the marine service I engaged ended up hauling her and moving her to their excellent shop. Having her out of the water with mast down, indoors, offers a number of good opportunities, one of which was to strip the bottom paint for refinish. We started that task with a grinder, and exposed the gel coat. Before the gel coat was revealed there were a few blisters to see--but not really much to see. Afterward the gel coat was bare, a large number of air voids under the gel coat and therefore incipient blisters were there to see. We ground all of these out for filling. Here's what she looked like:

Here's the surface appearance of the gel coat that reveals an air void below (both the thin crack and the bump in the surface):

Just for the record, all the repair has been done, and she has new gel coat, waiting for barrier coat and bottom paint, and she not only looks gorgeous, she's ready for another 50 years (I wish I were...). Here she is today:

I'm wondering how often owners do or have this done to their boats. Have you ever seen anything like what we found under the bottom paint of my boat?

Thanks for looking in!

 

[woodster]

i did that on my 79 s2 9.2a but i put on west system epoxy with barrier coat additive ....6 coats...... and will be soon putting on bottom paint ......nice job .....

regards

woody

 

[Squidd]

Been there Done That

http://forums.sbo.sailboatowners.com/showthread.php?t=140140&highlight=sanded+my+bottom

 

[PSR]

Thanks for the note Woodster. West System epoxy on the keel was one of the last steps in my job before the gel coat. Gel coat will be covered with multiple applications of Interprotect barrier coat epoxy.

 

[PSR]

Been there Done That

http://forums.sbo.sailboatowners.com/showthread.php?t=140140&highlight=sanded+my+bottom

My experience is nothing compared with what you faced Squidd. I skipped from the first page to the last in the thread but will read it all shortly. The result is awesome!!! Who would believe you could make the bottom you started with so beautiful in the end?? Seeing is believing. Wow!

 

[centerline]

you have a double posting with a different heading...

Hi,
just a friendly reminder.... if ya havent noticed already, you only need to post in one forum... posting in a couple of different ones only leads to duplicates showing in the "all discussions", which is rude, un-necessary, and against the forum rules...

if you hover over the "forums" tab, at the top left of the screen, you will see "all discussions".... this is where most of us read from as it shows all the postings within the site so we can see everything that may interest us, even though it may be posted in another forum that we dont frequent...

 

[PSR]

I thought about this, and my second round actually was a question for all Catalina owners, not just a description of the situation as in the middle size Catalina forum. I wanted to hear more about this, and I have as a result of the second thread. I'm really sorry about the doubling up, but there was a purpose--and they were not copies of each other even though they shared photos. Will I be keel-hauled??

 

[centerline]

I thought about this, and my second round actually was a question for all Catalina owners, not just a description of the situation as in the middle size Catalina forum. I wanted to hear more about this, and I have as a result of the second thread. I'm really sorry about the doubling up, but there was a purpose--and they were not copies of each other even though they shared photos. Will I be keel-hauled??

I dont think keel hauling is in order this time, but your daily ration of rum may be suspended...

 

[caguy]

I have blisters above the water line. The PO kept it in the water with a barrier coat in addition to the ablative coat. However when he went missing the boat sat at the dock and became partially submerged ( I' guessing about a year). I now have blisters above the boot line the bottom is in great shape.

 

[Chris Patterson]

How did you prepare the West epoxy for the gelcoat to adhere?
Looks very good.

 

[TLW]

That was my immediate thought, also - putting gelcoat over epoxy. I would like to hear how this was accomplished.

 

[Leroy McMillan]

I never heard of Epoxy over polyester…..and sticking for any length of time….good luck.

 

[Stargazer3]

I used the "SeaHawk" barrier coat on my 2000 h410. I think it came out very well. I had stripped the bottom and was going to apply VC-Offshore when I realized that this boat did NOT have a barrier coat as advertised! So - I had to do it. Capt Bill on STARGAZER

 

[jibes138]

Another question is why? Why put gel coat on at all? Seems like epoxy followed by Interprotect (or equivalent) and then paint would do the trick? Since we all cover that nice gelcoat with barrier coat and paint anyway the gelcoat seems like a weak link (porous, soft, prone to blisters).

 

[Richard Bryer]

Ahh- the memory is all too vivid still- I stripped the bottom this summer. Took much longer than anticipated- contractor turned out NOT to have the proper equipment to soda blast, VC Tar is a B----h to get off, and shoal keel are an awkward height. I ended up with the contractor using a heat gun and scraper then I sanded with a 6" orbital sander and 60 grit. When all was said and done the bottom was in excellent shape, very few blisters. I had made the decision to do the hull as the keel ( iron) badly needed work-thinking it wouldn't be THAT much extra work!! 4coats of IP 2000 later and a coat of VC17 and this is what it looks like:

 

[PSR]

...I had made the decision to do the hull as the keel ( iron) badly needed work-thinking it wouldn't be THAT much extra work!! 4coats of IP 2000 later and a coat of VC17 and this is what it looks like:

Great outcome, Richard. Thanks for the note!

 

[PSR]

Thanks for the observations on finishing. I am only a laborer in this work. The shop owner is a retired engineer who is a very thorough and demanding sail boat fan, and his assistant has 30+ years of experience working on FG boats. I'm following their instructions and trying both to be useful and not to get in the way. We scuffed the epoxy on the keel (it is only on the keel) and wiped with acetone before applying gel coat. There is epoxy + shredded glass + silica powder filler in all the repaired spots, and this has geen ground and sanded fair on the hull. Otherwise no special prep for the epoxy before the gel coat. Since you have asked, I will ask them about their thinking and let you know later. I will also ask about omitting the gel coat and simply finishing with epoxy.

Thanks again for the thoughts, experiences, and questions.

 

[TLW]

Much confusion here. Leroy mentions never hearing of epoxy over polyester. In fact that is done all the time - inter protect (epoxy) commonly used over gelcoat (polyester). It is the OTHER WAY AROUND that is the problem. Polyester over epoxy does not work - on several levels - chemically, mechanically, practicality.

I agree with Jibes that gelcoat is not needed in this situation. If the owner wants it for aesthetic reasons, then the repair up through the step of coating with gelcoat should be all polyester. Epoxy barrier coat after that is fine.

Richard's post was interesting as I purchased an O'day 31 this past Summer. It had VC-tar from 1986 or so. (a product that I was fond of at that time also) However, after 25 years the VC-tar had cracked all over - unsightly and leaving me unsure of its integrity. We removed it, found the gelcoat to be in perfect condition, and recoated with Interprotect. (see pics) I INSISTED that the tar be removed by sanding. Although some yards and independent contractors will blast VC-tar, most reputable (knowledgable) yards will not.

 

[robertsapp]

Since you're going to so much trouble, why not go the extra mile and put a permanent bottom on and not have to worry about this again for a couple of decades? Plus you'll be covered when they eventually get around to banning copper-based paints.

http://coppercoat.com/

 

[Delezynski]

Since you're going to so much trouble, why not go the extra mile and put a permanent bottom on and not have to worry about this again for a couple of decades? Plus you'll be covered when they eventually get around to banning copper-based paints.

http://coppercoat.com/

PSR,

Talking about a copper bottom.....
I applied the old CopperPoxy after taking Guenevere down to a bare bottom. It stated it was good for 10 years. We got 11 years from it and that was in the waters from San Francisco Bay to and through the Sea of Cortez. You can read about that on our web site, including a written report by our diver. We are VERY sad we can't get that product any longer.

We recently had Coppercoat applied to Guenevere. So, once again we had her taken down to a bare hull. You can see our Mini Op-Eval of it at our Youtube site at;
http://www.youtube.com/user/delezyn...id=UCyGH1-xOhCotpV_zhSzQq7g.3.op-eval&view=46

There is a part 1 of the application, and a part 2 from our first haul out.

Greg