Gelcoat blistering

For general discussion about the Cape Cutter 19

Gelcoat blistering

Postby Peter Pauling » Mon Nov 05, 2018 9:42 am

Hello. I am trying to discover if any CC19 owners have experienced problems of gelcoat blistering, which may or may not be related to osmotic action. I am especially interested in the later boats built by Honnor Marine.
Peter Pauling
CC19 Association Member
 
Posts: 3
Joined: Wed Jun 08, 2016 8:09 pm

Re: Gelcoat blistering

Postby Chris Wicks » Tue Nov 06, 2018 8:21 am

My Honnor Marine boat is from 2006. The 12th boat they produced I think. I have detected no signs of blistering. I remember noticing what I thought may be blistering around the waterline a few years ago. Just above the line of the antifouling. On closer inspection I realised this was simply a rougher finish to the gel coat intended for below the waterline. I would challenge anyone to notice it unless cleaning and polishing around the waterline. This is no cause for concern in my opinion, is this perhaps what you have noticed?

Cheers

Chris

Kaliope CC19 67
Chris Wicks
CC19 Association Member
 
Posts: 263
Joined: Thu Apr 02, 2009 6:39 am
Location: Platanias, Pelion, Greece and Funtington, Chichester, West Sussex.

Re: Gelcoat blistering

Postby Richard Rickard » Wed Nov 07, 2018 5:49 pm

Mine is No.50, a South African boat owned from new in 2003. No sign of any problem with the gelcoat apart from 'chalking' of the dark blue hull, which now has to be polished out every year.
Richard ('Nettie' 50)
Richard Rickard
Non Association Member
 
Posts: 17
Joined: Tue Dec 29, 2009 12:19 pm
Location: Mylor, Cornwall

Re: Gelcoat blistering

Postby Peter Pauling » Thu Nov 08, 2018 3:48 pm

Thanks for your remarks, Chris and Richard. Whilst I'm glad to hear that your older boats are still going strong, I'm more interested in the newer boats. What I'm talking about are thousands of closely packed small blisters, 1-5 mm diameter, covering 80% of the hull below the waterline on a newer boat. The surfaces affected were previously mirror smooth.
I personally believe they are osmotic blisters but I have never heard of this happening after only a short immersion period since first launch. I'm really fishing for advice on what to do about it - whether anyone else has experienced the problem, how they tried to resolve it, and whether their resolution was successful.
Best regards, Peter.
Peter Pauling
CC19 Association Member
 
Posts: 3
Joined: Wed Jun 08, 2016 8:09 pm

Re: Gelcoat blistering

Postby Chris Wicks » Thu Nov 08, 2018 4:12 pm

I'm sure others will reply. The condition you describe sounds very much like Kaliope. I was polishing her yesterday after a 6 month season afloat. It is like a stippling effect on the gel coat and it extends in places to just above the white strip around the waterline. In some light, it is almost invisible. I am certain it was always there and I didn't notice it. Why not contact Cape Cutter Yachts the new producers of Cape Cutters. I believe they have the same employees who were previously at Honnor Marine. They would tell you if when the hulls were laid up the gel coat below the waterline has a very slight stipple effect. If however your worst fears are realised it would make sense to involve them as to how to resolve the issue. Good luck.
Chris Wicks
CC19 Association Member
 
Posts: 263
Joined: Thu Apr 02, 2009 6:39 am
Location: Platanias, Pelion, Greece and Funtington, Chichester, West Sussex.

Re: Gelcoat blistering

Postby Nick Martin » Fri Nov 09, 2018 11:13 am

Hi Peter..
Juno is South African boat built and I haven't seen any signs of blistering .. Having seen a number of Honnor Marine boats in production in the past, they all had mirror-like finishes below the waterline - like most boats, and especially trailer-sailers ….. and, of course, antifouling was an option and not standard .. I cannot imagine how a stippled finish would be produced .. I believe the original moulds were shipped over from SA, so apart from lay-up materials, the boats should all be identical ..
Are you certain that the boat hasn't been painted - professional jobs can be incredibly convincing? - that certainly can lead to the trouble you describe..
As I'm sure you will have discovered, there are loads of articles on-line and in the mags about osmosis .. small blisters near the waterline can be a sign of early trouble, but it may not be a sign of anything catastrophic .. If you have antifouling, and have some blisters just below the waterline, then you could try popping one discretely and seeing what's going on?
Having said all that... I've been involved in boats for almost all of my life and I've never seen one sink or come to grief as a result of osmosis! .. It doesn't sound to me like you need to do anything apart from going sailing :)
Nick
Nick Martin
Non Association Member
 
Posts: 21
Joined: Sat Jan 08, 2011 10:43 pm

Re: Gelcoat blistering

Postby Dennis » Fri Nov 09, 2018 12:09 pm

Hello Peter

My boat 2008 #100 was antifouled when new with "Coppercoat" which basically is tiny particles of copper suspended in resin. I noticed a few weeks after it was first launched the problem you are describing, but in my case it was the antifouling resin which was blistering. Honnor Marine subsequently removed the "Coppercoat" and reapplied the same. The same thing happened again within weeks of relaunching. We came to the conclusion that the resin base of the antifouling was incompatible with the fresh water which my boat is moored in. After 10 years of use, the blistering is no worse than it was after about six weeks. My boat is moored on the water about 8 months per year.

I assume your boat is kept on Lac Leman, which is also fresh water. I understand that boats kept on fresh water are more prone to osmosis, however, I believe that Honnor Marine used resins which were specifically intended to prevent this problem.
Cheers

Dennis

CC19 #100 Mary Ann
User avatar
Dennis
CC19 Association Member
 
Posts: 1010
Joined: Fri Mar 27, 2009 6:29 pm
Location: Northumberland

Re: Gelcoat blistering

Postby Chris Wicks » Fri Nov 09, 2018 4:35 pm

All this has made me think again. The following article was useful. http://www.yachtsnet.co.uk/osmosis.htm I have been polishing Kaliope this afternoon. I accept it could be osmosis, and if so it has remained consistent since the boat was almost new. This year has been the longest season afloat. April to November in salt water. It's a condition I assumed could not be osmosis on what was a newish boat. I will keep monitoring it, but so far I have felt unconcerned year on year. Mine has normal antifouling, currently Hemple Tiger Extra.
Chris Wicks
CC19 Association Member
 
Posts: 263
Joined: Thu Apr 02, 2009 6:39 am
Location: Platanias, Pelion, Greece and Funtington, Chichester, West Sussex.

Re: Gelcoat blistering

Postby Peter Pauling » Fri Nov 09, 2018 7:09 pm

Hi Nick and Dennis,
Many thanks for your observations.
Interesting coincidence, my boat is named "Mariana".
I know coppercoat antifouling well. However my boat was launched free of any antifouling as local boatyards recommend a season afloat before antifouling in order to remove traces of wax from hull molds.
The gelcoat blisters in my hull became evident after only two and a half months afloat, on immersed surfaces that were previously mirror smooth.
If it turns out that these blisters have occured in older boats which have been merrily sailed for 10 years or so, well then I would be relieved and happy. I would just apply a few good coats of preventive barrier paint, some antifouling, and then sail off with a smile on my face!
I would still be wondering why the blisters are there. I have owned many GRP boats, and never heard of this problem in a new boat...
Best regards, Peter,
Peter Pauling
CC19 Association Member
 
Posts: 3
Joined: Wed Jun 08, 2016 8:09 pm

Re: Gelcoat blistering

Postby zimp » Tue Nov 13, 2018 1:40 pm

Our CC19 has hull number 4, so a SA boat. No blistering at all.
Bert, CC19, #004, s/y Zimp
zimp
Non Association Member
 
Posts: 77
Joined: Tue May 25, 2010 12:59 pm
Location: Netherlands

Next

Return to General Chat

Who is online

Users browsing this forum: No registered users and 3 guests