Will blisters be noticeable after couple years dry storage?

[Roswell715]

I do feel like I searched this forum and google pretty well, so I do apologize. I feel like this is most likely answered somewhere here already.. I just couldn't find it.

When looking at a boat and checking for blisters: Are blisters going to be noticeable if the boat has been on the hard for a couple years, with time to dry out?

There are no obvious signs of cosmetic type blisters - or deep osmosis type blisters for that matter ( visibly, anyway ).
Its a freshwater boat that has been in heated storage for two years. 1978 Cape Dory 27

I did buy the boat at a bargain, since either way it was a steal. I am curious if I am better off putting in the water for a few months to let any blisters soak up...or should I just start a full bottom job right away?

[NevilleCat]

Originally Posted by Roswell715

I do feel like I searched this forum and google pretty well, so I do apologize. I feel like this is most likely answered somewhere here already.. I just couldn't find it.

When looking at a boat and checking for blisters: Are blisters going to be noticeable if the boat has been on the hard for a couple years, with time to dry out?

in my limited experience, and in warm conditions, blisters became more apparent after the boat came out of the water and the hull heated up.
Both osmotic blisters and blisters between the surface (paint/epoxy) layers.

[jordanbigel]

In my experience (20 years with a boat that has a chronic blister problem), when you haul out, if you look with good lighting with the hull dried a bit (after pressure washing), at the right angle, if they are there you will see them clearly. If you cannot see them it is because you do not have them.

If they are not there, then a few weeks or months in the water is not going to make them suddenly appear.

[CSY Man]

There are no obvious signs of cosmetic type blisters - or deep osmosis type blisters for that matter ( visibly, anyway ).

How hard is it to post a picture?
Try it and you will get better responses.

[GordMay]

Greetings and welcome aboard the CF, Roswell.

Originally Posted by CSY Man

How hard is it to post a picture?
Try it and you will get better responses.

IIRC, you cannot post a picture, until you have over [10?] posts. The OP has 2.

[Roswell715]

Originally Posted by CSY Man

How hard is it to post a picture?
Try it and you will get better responses.

I would not want a picture because I am not looking for a specific diagnosis. There is nothing to see right now.

The situation is this:
There do not appear to be signs of blistering. But, my uncle mentioned that I might not be able to see them because the boat has been on the hard for years. Therefore a moisture meter would probably not be effective either.

Once I get the paint off, should any major blistering be obvious? I.E> discoloration of fiber/gel, etc.

Or, is there a chance I could get the bottom all done, only to have some blisters bulge up once the boat is wet for a while? Should I put it in the water for the summer before doing the bottom job?

[hugosalt]

Welcome to CF, and much enjoyment to you with your new boat.
My 1st thought was if your having concerns of any kind just put on anti fouling
and examine/evaluate at end of season.
However after some thought...if there is no sign of any problem on bottom
now would be a good time to do a good bottom job and apply a barrier coat.
Reasoning being you never want to seal in moisture under a barrier coat
...and your bottom will never be as dry as it is now after several years of
indoor heated storage.

In the end I think your good either way as currently there is no problem
and unlikely to present one at this time.
No expert here, just some thoughts.
Luck

[Rucksta]

The boat is as dry now as it ever will be short of a peel and vacuum bag.
Osmosis is not as big a problem in fresh as it is in salt water.
Osmosis is slow, splashing the boat may not reveal latent voids.
Extended splash will make the boat wet requiring restart the drying process.
Splash and haul out will cost about the same as bottom paint.

You could hedge by drilling some blind holes in the layup.
Seal some sarin wrap over the holes and examine for moisture.
Plug the holes with thickened epoxy when you're done.

If you bought a cheap boat you are likely an optimist.

Sand, paint - key coat, antifoul launch and hope for the best.
If the worst occurs you've lost a coat of paint and no longer have a cheap boat.

At least you got to sail it while the dream endured.

Alternately complete sand barrier coat key coat & antifoul.
It may be enough to prevent any latent osmosis from representing.

P.S. a few blisters does not sink a boat.

[Tsuru]

It’s hard to say if you will see blisters after the hull has dried out. If it was me I’d hammer sound the hull. Get the smallest ball peen (some use hard plastic) hammer at the hardware store. Use it to tap and sound the entire hull. You will clearly hear the difference between a sharp tap and a dull thud and when an area of deamination is discovered.
If it all sounds the same, I’d consider it good to go. That said it would be a good time for a barrier coat.
Good luck,

[Orion Jim]

Originally Posted by Roswell715

I do feel like I searched this forum and google pretty well, so I do apologize. I feel like this is most likely answered somewhere here already.. I just couldn't find it.

When looking at a boat and checking for blisters: Are blisters going to be noticeable if the boat has been on the hard for a couple years, with time to dry out?

There are no obvious signs of cosmetic type blisters - or deep osmosis type blisters for that matter ( visibly, anyway ).
Its a freshwater boat that has been in heated storage for two years. 1978 Cape Dory 27

I did buy the boat at a bargain, since either way it was a steal. I am curious if I am better off putting in the water for a few months to let any blisters soak up...or should I just start a full bottom job right away?

What is your definition of a “full bottom job”?
No fiberglass boats from the era are immune, but Cape Dory 27’s have not exhibited a propensity for blistering.
As noted previously you are now in a position to remove any existing bottom paint, down to the original gel coat, inspect thoroughly, and apply the barrier coat of your choice followed by the antifouling of your choice.
Two years on the hard in heated storage has provided the optimum conditions to start this project. You may want to visit The Cape Dory Board • Index page to mine the experience of other Cape Dory owners.
Good luck!

[Pete7]

Originally Posted by Roswell715

Its a freshwater boat that has been in heated storage for two years. 1978 Cape Dory 27

..or should I just start a full bottom job right away?

A completely dry boat is unusual and a great opportunity to have an epoxy paint layer before applying the antifoul paint.

It really depends how long you intend to keep the boat and if you are up for the extra work and cost involved. Removing the old antifoul will be a horrible job.

Pete

[Cheechako]

If they were ground out and filled well you wont know unless you strip the paint.
Once you strip the paint you can see them and if they are not bulging, well ....you dont have blisters. If they are bulging even a couple thousanth's, they will be seen when you sand.
Why strip the paint? Go sailing.

[glenn.225]

What is the type/condition of the bottom paint now? If you don't know the type you may have to remove it anyway, not all types are compatible.


When I first got my boat the paint was not in good condition, patches falling off, big globs in some areas. So I decided to remove it, experimented with sanders and grinders of various grits but had best results (i.e. fastest removal and least damage to gell coat) with a plain old paint scraper. Use type with knob (https://www.homedepot.ca/product/a-r...nob/1000475279) keep the blade sharp, you'll want a few spare.

IIRC it was about three days of hard work and I was at the time in pretty good shape. Anyway after it was all scraped and then sanded smooth I put on three coats of Interlux InterProtect 2000E barrier coat and then three coats of VC17 since I too am in fresh water.



Since then I pressure wash when it comes out in the fall, spring time I give it a very quick once over with a green 3M pad by hand and put one coat of VC17 and that's been it for 12 or so years.

If I don't sail much that year I get some slime build up but if I sail a good bit that year I have almost nothing in the fall.

[Celestialsailor]

My Westsail has been on the hard for 10 years. 8 years in the Northwest and 2 years here. The visible blisters are the diameter of a pea. My procedure is to use a 6-8" sander with 40-60 grit and lightly sand to highlight the blisters then use a 1/2" ball carbide grinder to open them up. On a boat that has been drydocked this long, I am not finding any moisture in them...especially where I am gets into the 100s in the summer. Repair of them is epoxy, cabosil and a touch of mill fibers.

[boatpoker]

Not so serious -
Gelcoat blisters and blisters in the skinout mat are almost always small, cosmetic and can disappear if dry enough, often within a day or two of haulout. Unlikely to be found by moisture meters or percussive sounding.

Serious & expensive -
Interlaminate blisters are loften large, different and involve hydrolysis. They involve huge repair bills and can be located with moisture meters and percussive soundings no matter how long they have been out of the water.

Moisture Meter Mythology