Below the Bottom Paint

[rubyjean]

I think the main reason to barrier coat is to stop the glass from absorbing water. My Haida 26 was built in 1969, before they[deq] stopped manufactures from using the old resin, can't remember what they had to take out, but the newer resin is more porous. This year we hauled out to load onto my trailer, over the next few day's it must have lost at least 500#'s of water according to the trailer springs. I had noticed that my boat was getting slower and setting a little lower to the boot stripe. So my goal is to stop the absorbtion to help keep weight down. I could be wrong with my thinking, but this is what I belive...Michael..

[sailorboy1]

Originally Posted by minaret

Do you live in a fresh water or brackish estuary?

nope!

[minaret]

Originally Posted by rubyjean

I think the main reason to barrier coat is to stop the glass from absorbing water. My Haida 26 was built in 1969, before they[deq] stopped manufactures from using the old resin, can't remember what they had to take out, but the newer resin is more porous. This year we hauled out to load onto my trailer, over the next few day's it must have lost at least 500#'s of water according to the trailer springs. I had noticed that my boat was getting slower and setting a little lower to the boot stripe. So my goal is to stop the absorbtion to help keep weight down. I could be wrong with my thinking, but this is what I belive...Michael..

Make sure she reads nice and dry on the moisture meter before barrier coating. If she was saturated enough to affect the waterline it's a severe case. I could see where boats in that size range could easily be more affected in that regard by saturation. If you put a meter on it and find it's saturated I'd be happy to give you some pointers on fast hull drying techniques if you are interested. The "poor man's hotvac" would be perfect in your size. Beats drying on the hard for months.

[rubyjean]

Originally Posted by minaret

Make sure she reads nice and dry on the moisture meter before barrier coating. If she was saturated enough to affect the waterline it's a severe case. I could see where boats in that size range could easily be more affected in that regard by saturation. If you put a meter on it and find it's saturated I'd be happy to give you some pointers on fast hull drying techniques if you are interested. The "poor man's hotvac" would be perfect in your size. Beats drying on the hard for months.

The boat is sitting in the Oregon desert till work is done. The humitity here will be about 15% soon and has been freeze drying all winter. Two weeks at this % will be dry before I'm ready to start. Thanks..Michael..

[minaret]

Originally Posted by rubyjean

The boat is sitting in the Oregon desert till work is done. The humitity here will be about 15% soon and has been freeze drying all winter. Two weeks at this % will be dry before I'm ready to start. Thanks..Michael..

Nice. I floated the John Day a few years back, that makes me want to go again. It was a great two weeks in stunningly beautiful country with just the guys. The water was up and we hit some class 4's, got lots of good fishing in too. Having kids is tough...
Don't be surprised if it's not drying as quick as you'd like though. If you air dry like that make sure to scrub the bare fiberglass bottom with soap and water once a week. The water that weeps out of the laminate has lots of salt and styrene in it, it forms a film on the surface which will retard drying if you dont wash it off. I've dried hulls under infrared heat at over a 100 degrees for months before and had them barely go down on the meter. It's complicated.

[Cheechako]

Originally Posted by Don Lucas

nope!

If you're gonna haul and do the big job next year anyway. Why not try just roughing up the bare spots and bottom painting on them? You/we might all learn something. I've never been convinced that Intelux 2000 really does much at all, but always went along with the yard workers advice, who went along with what the boss told them, who went along with what the Interlux rep told him, who went along with what the distributer told him..... etc.
I had a 44 footer that was in the yard for 4 mos for a major rebuild and paint. It was 10 years old and had zero.. as in not one.. blisters. The bottom was stripped completely (didnt appear to be any thing I could indetify as primer) as it had many layers of bottom paint. It was repainted with interlux 2000 and bottom paint. 1.5 years later when the boat was sold and went to survey it had some (not too many) blisters. While I wouldnt say the 2000 caused the blisters, it sure didnt prevent them!

[sailorboy1]

I do have some spots that must have flaked last year when the dealer prepped the boat because they have a gray colored "something" on them. And while I didn't the bottom before it was power washed on haul out where some hard growth right in the middle of those. To me this suggests that the anti-foul didn't stick to whatever that gray crap was.

[Ex-Calif]

Originally Posted by Don Lucas

I do have some spots that must have flaked last year when the dealer prepped the boat because they have a gray colored "something" on them. And while I didn't the bottom before it was power washed on haul out where some hard growth right in the middle of those. To me this suggests that the anti-foul didn't stick to whatever that gray crap was.

How many coats last year? Any pics of the hull and flaking? One year on anti foul sounds like good money after bad. However I understand the desire to get another season in and defer it to next year. You're advantage is cold boats haul out every year. I like to keep mine in as long as possible.

If you really only need to get another year, sand prep and throw a couple of coats of ablative back on. It will survive your 6-8 month season. Plan well for next year, get as much of the old crap off, get a good prime coat for bonding and then top coat.

The paint ain't cheap and with your short seasons you should be getting 3 years calendar or 18-24 months in the water between paintings.

[sctpc]

Originally Posted by Ex-Calif

The paint ain't cheap and with your short seasons you should be getting 3 years calendar or 18-24 months in the water between paintings.

I found the prep 10 times more expensive than a coupleoff hundred bucks. Mine is now over a year and looks like its just been done also the first two coats are light blue and last two are dark blue so when it gets down I will get a worning . So if I were you Don I would put on as little as I could.

[sailorboy1]

The bottom paint was $245, which to me is cheap compared to the work and time to prep and apply. I'm not inclined to try and save $100 of paint just because I'm stripping next year. If I were to go down this thinking line pretty soon I would be saying not to anti-foul at all.

Back to the primer part of the orginal question - I'm only asking about priming the spots that the old hard paint has flaked off as I don't know what layer I'm looking at at those spots.

[psneeld]

Originally Posted by MarkSF

Some manufacturers get blisters, and some hardly ever do. Correct me if I'm wrong, but 80s Bristols did not get a barrier coat. Yet 30 years later, they are blister-free. Are you saying after 30 blister-free years it's going to erupt into blisters in the next 3? No, because it was properly laid-up and cured. Sure, if your hull is hastily and badly constructed you want to do everything you can to keep water out. I hope you're putting the barrier coat on the inside of the bilge, too.

Obviously haven't read much on the subject relating to what can happen based on different scenarios.

You can have severe hydrolysis going on and no blisters.

After stripping off as many as 6 layers of laminate by hand in some places on my boat and others...you'll think twice about what the marine industry knows about blisters. Read the writings of the composite tank and pipe industry...they seem to understand the roblem better.

NOT ALL boats will dry out in less than several years (maybe much longer) unless you take the gel coat OFF as well as the wet laminates. It's like keeping water in a tupperware container. Even after 2 months in the dry reasonably warm fall/winter we just had, I had huge, juicy blisters right next to deeply ground spots...little migration or evaporation even after 2 months.

Polyester Gel coat is worthless... it's there to sell the boat and is actually just something that needs to be removed once you get moisture in the hull...vinylester can be better but only marginally in some cases.

I recommend to everyone that a barrier coat be used if your boat is going to sit in warm water all year long.

[CharlieCobra]

Originally Posted by Don Lucas

The bottom paint was $245, which to me is cheap compared to the work and time to prep and apply. I'm not inclined to try and save $100 of paint just because I'm stripping next year. If I were to go down this thinking line pretty soon I would be saying not to anti-foul at all.

Back to the primer part of the orginal question - I'm only asking about priming the spots that the old hard paint has flaked off as I don't know what layer I'm looking at at those spots.

Sherwin Williams Pro-Line Barrier coat comes in white as well. It's tough to tell what, exactly, is under that bottom paint. To reinforce what Minaret said, ALL Gelcoat is porous and water resistant, not waterproof. Epoxy is waterproof.

[minaret]

Originally Posted by psneeld

Obviously haven't read much on the subject relating to what can happen based on different scenarios.

You can have severe hydrolysis going on and no blisters.

After stripping off as many as 6 layers of laminate by hand in some places on my boat and others...you'll think twice about what the marine industry knows about blisters. Read the writings of the composite tank and pipe industry...they seem to understand the roblem better.

NOT ALL boats will dry out in less than several years (maybe much longer) unless you take the gel coat OFF as well as the wet laminates. It's like keeping water in a tupperware container. Even after 2 months in the dry reasonably warm fall/winter we just had, I had huge, juicy blisters right next to deeply ground spots...little migration or evaporation even after 2 months.

Polyester Gel coat is worthless... it's there to sell the boat and is actually just something that needs to be removed once you get moisture in the hull...vinylester can be better but only marginally in some cases.

I recommend to everyone that a barrier coat be used if your boat is going to sit in warm water all year long.

Trying to dry a hull with the gelcoat on would be the height of foolishness. We can dry a saturated hull in two weeks with our hotvac system. And it gets much drier than it ever would air drying. As I said before I've seen cases where the boat was dried under infrared heat for many months with little to no effect in the days before the hotvac.

[CharlieCobra]

Minaret, clear your PM's, you're over the limit....

[minaret]

Originally Posted by CharlieCobra

Minaret, clear your PM's, you're over the limit....

Yea, sorry, it happens ALL THE TIME because I won't use Paypal to upgrade so I'm limited to 50 PM's. If I don't constantly stay on top of it I'm full. Handled it.