Got blisters? Not any more!

by **Dolphin** » Tue Jun 21, 2011 11:23 pm

Felicite is on the slips. We investigated a few "inconsistencies" in the hull. The blister on the left is still to be ground out further to follow the osmosis, indicated by the dark line in the fibreglass. The grey is the filler between the ballast and the hull. This was professionally done at Lake Macquarie.
The hull is now better than new! I just have to sell the boat to pay for the repairs.

A full insurance survey was done. Safety gear, sails, seacocks etc. were checked visually. No skin fittings were replaced but a plastic ball valve was removed and a Marine valve had to be used instead. Brass gate valves are frowned upon. An old sumlog was replaced. The surveyor checked for any hull penetrations that were not being used (sumlog) and they were removed and glassed over to reduce the risk of sinking.

We nearly finished painting before the 50kt front came through. Felicite still didn't fall over.

: Blisters, the grey line in the left one is the osmosis, more to go!; P1020696a.jpg (58.26 KiB) Viewed 3669 times

by **Miker** » Wed Jun 22, 2011 2:59 pm

Doesn't look so bad Greg, hopefully that larger one will peter out quickly.

I had a couple like this on Dulamara in Feb. All but one hadn't changed in a few years, so we left them. One had weeps, so we ground it out. Will do some more next slip.

Michael

by **Tales** » Fri Jun 24, 2011 9:07 am

Over the years I have had about 30 blisters dealt with by grinding out and repairing.

The TH hulls are reasonably thick so it doesn't seem to be a problem.

Although purists criticize chopper gun sprayed hulls (compared to woven cloth) the ozmosis only runs along to the end of each fiber - which has a finite length - so it can't spread far.

When I see a blister I have it fixed straight away.

Cheers,

Tom

by **Dolphin** » Fri Jun 24, 2011 3:31 pm

I was talking to Bear and he was saying that some boats have a typical spot that blisters appear and that my be how they are constructed in the mold ie hot spots or hard to get to spots. Where have the blisters been in other boats?
I've had about 8 20cent size blisters in the rudder and some the same size above the propellor aperture on the hull. These are the biggest I've seen on Felicite. When I was about to put her back I noticed in the light that there were more on the port side.

Greg.

by **storm petrel** » Fri Jun 24, 2011 7:03 pm

I have had not any blisters on Storm Petrel(Mk2) to date. Which Mk are the blisters appearing on mostly?
Cheers,
Mark

by **Dolphin** » Wed Aug 10, 2011 10:05 pm

I have found out from the rigger Bryan Philips that osmosis is caused by a bug called an Osmosis Mite. That is the clicking sound you can hear under the hull in the water as they chew through the fibre glass. They are related to the termite.
I'll look it up on the web.
Greg.

by **surrealbass** » Thu Aug 11, 2011 10:08 am

Just had to check the calendar then- sure it's not April 1st!!!! I had better hurry up and get joylee out of the water QUICK as if that is the case then my timber tophat has osmosis REAL BAD!!! :lol: