Getting to the bottom of it... (Ablative question)
 

Hi, Jere, and group,

Jere Lull wrote:
In article .com,
"Skip Gundlach" wrote:

Our boat is covered in poorly repaired blisters.

Dang! It's always something, isn't it?

I'd review http://yachtsurvey.com/blisters.htm (again) before you
continue. Our 35 year-old non-epoxy is still fine, and epoxy has serious
drawbacks.

I'm quite familiar with Pascoe's site - marvelous resource - but am
wondering about drawbacks. This boat was previously peeled, and barrier
coated with something - presumed to be epoxy - which is evident in the
grinding/sanding process. I'd thought the normal barrier coat *was*
epoxy (??)...


Because you already have a reveal coat, I'd stick with the current
color. No need to get confused whether a patch is the first or second
red layer.

Heh. We'll have had to go through all the blue first - and I presume
we'd have had to go through the red, if that's what we use on top - so
it ought to be a last-ditch "gotta get paint on this, *NOW* sort of
thing.


And don't scuff for adhesion -- since there's not much to be had, it IS
intended to be ablative and the fresh coat will chemically etch and bond
-- but only slightly for roughness. No need to remove stuff that's still
good.

What about all the oxidation, cleaner runoff from PoliGlow prep (not
yet applied; stay tuned), and other indignities on the otherwise clean
bottom?

Thanks for any real-world experience. Ours will next to never be out
of the water, so we'd like to do as much to extend the time between
repaints as possible...

L8R

Skip and Lydia

Morgan 461 #2
SV Flying Pig
See our galleries at http://justpickone.org/skip/gallery/
Follow us at


"And then again, when you sit at the helm of your little ship on a
clear
night, and gaze at the countless stars overhead, and realize that you
are
quite alone on a great, wide sea, it is apt to occur to you that in the
general scheme of things you are merely an insignificant speck on the
surface of the ocean; and are not nearly so important or as
self-sufficient
as you thought you were. Which is an exceedingly wholesome thought,
and one
that may effect a permanent change in your deportment that will be
greatly
appreciated by your friends."- James S. Pitkin

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/

Getting to the bottom of it... (Ablative question)
 

If it's a normal ablative paint, it should still be as effective upon
splashing as the day it was applied; think of a bar of soap. And it's
not an irreversible situation, why not splash and see how it goes? If
the paint's ineffective, you can haul and take care of it. You'll be
hauling every few years anyway, so it's a case of hauling sooner than
expected the first time, if the paint's somehow become no good.

Skip Gundlach wrote:
As many of you know, we're close to splashing our 2-year refit. It was
newly ablative bottom painted when we bought it.

A local asserts that the bottom paint is dead, and it will have to be
redone.

How say you who have experienced this? Not hard, ablative, out of the
water for a couple of years essentially immediately after application?

If it has to be redone, do I have to take off the old paint as well?
Or, with a scuff-up, will the bottom adhere, and (perhaps?) re-activate
the old stuff?

Meanwhile, some of you who had previously asked have received an
invitation to join our yahoogroups log list. If you'd like to hear
about our adventures, join up with the link below...

L8R

Skip

Morgan 461 #2
SV Flying Pig KI4MPC
See our galleries at http://justpickone.org/skip/gallery/
Follow us at

"Twenty years from now you will be more disappointed by the things you
didn't do than by the ones you did do. So throw off the bowlines. Sail
away from the safe harbor. Catch the trade winds in your sails.
Explore.
Dream. Discover." - Mark Twain

Getting to the bottom of it... (Ablative question)
 

In article .com,
"Skip Gundlach" wrote:

Jere Lull wrote:

I'd review http://yachtsurvey.com/blisters.htm (again) before you
continue. Our 35 year-old non-epoxy is still fine, and epoxy has serious
drawbacks.

I'm quite familiar with Pascoe's site - marvelous resource - but am
wondering about drawbacks. This boat was previously peeled, and barrier
coated with something - presumed to be epoxy - which is evident in the
grinding/sanding process. I'd thought the normal barrier coat *was*
epoxy (??)...

Epoxy/Barrier coat only *slows* water migration. NOTHING will stop the
water getting in, particularly since a significant source of moisture is
the bilge, on the other side of the hull. More than that, I'll leave to
Pascoe, who I think described it nicely.

The problem with epoxy is that nothing sticks to it well -- the best you
can get is a mechanical bond. If you can be assured that you never will
have to deal with an area again, go with epoxy, but I'll use a good,
fresh polyester for everything else as the next layer will slightly
chemically bond to the previous one to give a greater grip than a pure
mechanical bond.

As far as the paint goes: Ablative doesn't go bad for the purposes we're
talking. Oxidation, stuff spilled on it, whatever, won't make much
difference after a few miles.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/

Getting to the bottom of it... (Ablative question)
 

"Jere Lull" wrote

The problem with epoxy is that nothing sticks to it well -- the best you
can get is a mechanical bond. If you can be assured that you never will
have to deal with an area again, go with epoxy, but I'll use a good,
fresh polyester for everything else as the next layer will slightly
chemically bond to the previous one to give a greater grip than a pure
mechanical bond.


Jere,
I am puzzled by the above statement. It is not what I thought was generally
accepted.

One of the problems with fibreglass repairs done using polyester resin, is
that secondary bonding (new polyester to old polyester) has poor strength.
This is generally accepted in the industry. Epoxy resins have superior
secondary bonding strength for fibreglass repairs. But, due to cost, most
fibreglass repairs are done with polyester.

When it comes to blister repair, 2-part epoxy pastes are the norm. Even the
website you referenced says that:
http://yachtsurvey.com/BlisterFail2.htm

If your concern is overcoating an epoxy barrier coat, then following a
manufacturer's procedures is important. Interlux have a system for their
Interprotect barrier coat which if followed works well. It should be well
documented on their web site.

It was interesting to read the yachtsurvey site. He is adamant that boats
should not be sandblasted. There is some basis for this, because often the
sandblasting only exposes some bubbles, but in other areas it just removes
more of the gelcoat leaving unexposed bubbles below. Peeling may be better,
but sometimes this process is not available or is just too expensive. I have
personally seen medium to heavy sandblasting , followed by grinding of
individual blisters carried out successfully (maybe 30 or more boats) - By
that I mean 15+ years with no blisters re-appearing. In all cases, the
Interprotect system was used with either Micron or VC-17 antifouling.

I believe that one of the biggest reasons for blister repair failures is not
allowing the hull to dry after sandblasting or peeling. In southern climes,
this can be almost impossible to achieve without building a dehumidified
enclosure. We have probably had much better success because in the North, it
is very dry in the winter - and the boats can dry for 5 or 6 months because
owners are not too anxious to go sailing Nov-Mar!

Even today, anyone buying or building a new boat should consider having 4 or
more coats of epoxy applied before applying antifouling. Follow paint
manufacturer's instructions for hull dewaxing and other preparation. Boats
in our area treated this way have NEVER had blisters.

Getting to the bottom of it... (Ablative question)
 

Jere Lull wrote:

In article .com,
"Skip Gundlach" wrote:

The plot thickens (like epoxy in hot weather)...

Our boat is covered in poorly repaired blisters.

I don't know how, if you hauled the boat for survey and had any kind
of competent surveyor you got a boat that you didn't know was
blistered

When we bought our boat it was 20 years old. The PO had peeled the
bottom and put on 20 coats of epoxy IIRC. When we hauled it for the
survey, the surveyor said there were 'cosmetic' blisters - he pointed
them out to me, and I saw them.

We decided to do nothing.

We've never seen the blisters again.

The max we've seen are a couple around the waterline at the edge of
the epoxy coat.

We've always had the boat either red or blue (alternatively), because
we heard that whales don't like black hulled boats or another color
that I can't remember what it is.

Dang! It's always something, isn't it?

I'd review http://yachtsurvey.com/blisters.htm (again) before you
continue. Our 35 year-old non-epoxy is still fine, and epoxy has serious
drawbacks.

Because you already have a reveal coat, I'd stick with the current
color. No need to get confused whether a patch is the first or second
red layer.

And don't scuff for adhesion -- since there's not much to be had, it IS
intended to be ablative and the fresh coat will chemically etch and bond
-- but only slightly for roughness. No need to remove stuff that's still
good.

Getting to the bottom of it... (Ablative question)
 

In article ,
"OldSailor" wrote:


"Jere Lull" wrote

The problem with epoxy is that nothing sticks to it well -- the best you
can get is a mechanical bond. If you can be assured that you never will
have to deal with an area again, go with epoxy, but I'll use a good,
fresh polyester for everything else as the next layer will slightly
chemically bond to the previous one to give a greater grip than a pure
mechanical bond.


Jere,
I am puzzled by the above statement. It is not what I thought was generally
accepted.

One of the problems with fibreglass repairs done using polyester resin, is
that secondary bonding (new polyester to old polyester) has poor strength.

I did say "slightly". Having tried to do more work on top of epoxy, I
won't do it again. I used to have a site to cite, but can't find it
off-hand and won't get much time to look for it until sailing season is
over -- I get only one day a week on usenet with the amount of time
we're out.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/

Getting to the bottom of it... (Ablative question)
 

Would that mean the object appears black, or white?

I can't believe transparent.

Roger

http://home.insightbb.com/~derbyrm
"Charlie Morgan" wrote in message
...
On Thu, 24 Aug 2006 17:21:38 GMT, Rosalie B.
wrote:


We've always had the boat either red or blue (alternatively), because
we heard that whales don't like black hulled boats or another color
that I can't remember what it is.


Whales cannot see the color blue.

CWM

Getting to the bottom of it... (Ablative question)
 

Hi, grandma, and group,

Rosalie B. wrote:
Jere Lull wrote:

In article .com,
"Skip Gundlach" wrote:

The plot thickens (like epoxy in hot weather)...

Our boat is covered in poorly repaired blisters.

I don't know how, if you hauled the boat for survey and had any kind
of competent surveyor you got a boat that you didn't know was
blistered

Did I say that i didn't know about them? The boat was represented to
us as no-blisters, and on haulout, I was nearly ready to walk. As it
was, i sulked through most of the sea trial, I was so bummed.

What had me bummed was two things: It obviously wasn't "no blisters" -
and what was there was poorly repaired prior blisters, or poor
application of the barrier coat or both. The blisters we saw mostly
went "thock" rather than squish (well, I can't say that *any* went
"squish").

Now, on sanding or grinding them, they're nearly all dry - but
definitely blistered. Only a few have had a chemical smell to them,
which, because the boat has been on the hard for more than 2 years,
clearly shows that the problem was under the barrier coat in those.
Worse, most of the time, we see prior blue marks from where someone
used a sharpie over the red coat to mark the blister.

Some of these are substantially under the barrier coat - thus the
"thock" when you hit it. Others of them just make a dull sound where
there used to be, all around it, sharp report.

After all that, though, like most blisters, and as Pascoe points out,
it's not a structural issue. It's just "do it right" so we don't have
to do it again. It's a pain in the neck, but the exterior of this boat
will look as new, so we might as well get the bottom while we're donig
it.

When we bought our boat it was 20 years old. The PO had peeled the
bottom and put on 20 coats of epoxy IIRC. When we hauled it for the
survey, the surveyor said there were 'cosmetic' blisters - he pointed
them out to me, and I saw them.

We decided to do nothing.

We've never seen the blisters again.

Resisting the obvious question of haulouts or inspection, I presume you
must be very lucky. Having a blister disappear isn't nearly as common
as having more occur after barrier coating, AFIK.


The max we've seen are a couple around the waterline at the edge of
the epoxy coat.

We've always had the boat either red or blue (alternatively), because
we heard that whales don't like black hulled boats or another color
that I can't remember what it is.

Hm. I'd not heard that. The current coat is blue, and Lydia wants to
go back over, once the blisters are repaired, and those spots touched
up, with black. I'm not sure how many whale problems there are in the
Caribbean, so I don't know that it's worth worrying about, but, then
again, the Caribbean, as seen in some of the mailing lists of which I'm
part, may not be so safe for other more political reasons.

So, we're going to fix them all, put blue over all the repairs, and
then put a very heavy application of new ablative, with more on the
waterline and rudder, accompanied by PropSpeed on the running gear,
which is new between the tranny and the prop, dripless packing included
(Thanks, Roger!).

Due to all the repairs which have been done by that time, once all the
repairs have been overcoated after fairing, we'll give a toothcoat
sanding to all of it and then commence to bottom painting while Lydia
does the Poli-Glow. News at 11, so to speak, in my usual voluminous
galleries.

Current project(s) are rewiring the forward bilge pump, relocating and
replumbing the aft bilge pump, and hardpiping the aft head (along with
new supply hose and new cockpit scupper monster hose, all of which
lives under the aft head platform).

Lydia's started her occasional mailing of the news of the day from the
warm-fuzzy side in the google group Flying Pig Log, and I pop into the
yahoogroup The Flying Pig Log less frequently but with more detailed
and technical commentary, for those interested...

L8R

Skip and Lydia, sweltering in the St. Pete Hete

Morgan 461 #2
SV Flying Pig KI4MPC
See our galleries at http://justpickone.org/skip/gallery/
Follow us at

"Believe me, my young friend, there is *nothing*-absolutely
nothing-half
so much worth doing as simply messing, messing-about-in-boats; messing
about in boats-or *with* boats.
In or out of 'em, it doesn't matter. Nothing seems really to matter,
that's the charm of it.
Whether you get away, or whether you don't; whether you arrive at your
destination or whether you reach somewhere else, or whether you never
get anywhere at all, you're always busy, and you never do anything in
particular; and when you've done it there's always something else to
do,
and you can do it if you like, but you'd much better not."

Getting to the bottom of it... (Ablative question)
 

Jere Lull wrote:
I did say "slightly". Having tried to do more work on top of epoxy, I
won't do it again.

I wonder if the problem was amine blush. This is a waxy film
that develops across the surface of most epoxies as they cure.

I've done secondary bonds using epoxy quite a lot... both
epoxy to epoxy, and epoxy to polyester... and found it to be
so much superior to polyester that I won't even bother with
polyester resin any more.

One problem with epoxy is that it can form a much more dense
surface and be very much harder to work/shape than
polester... an argument in favor of getting it right the
first time. Using peel ply & barrier film helps a lot!

Fresh Breezes- Doug king

Getting to the bottom of it... (Ablative question)
 

"Skip Gundlach" wrote:

Hi, grandma, and group,

Rosalie B. wrote:
Jere Lull wrote:

In article .com,
"Skip Gundlach" wrote:

The plot thickens (like epoxy in hot weather)...

Our boat is covered in poorly repaired blisters.

I don't know how, if you hauled the boat for survey and had any kind
of competent surveyor you got a boat that you didn't know was
blistered

Did I say that i didn't know about them? The boat was represented to
us as no-blisters, and on haulout, I was nearly ready to walk. As it
was, i sulked through most of the sea trial, I was so bummed.

OK - that wasn't clear and I didn't remember that, or maybe I missed
it.

What had me bummed was two things: It obviously wasn't "no blisters" -
and what was there was poorly repaired prior blisters, or poor
application of the barrier coat or both. The blisters we saw mostly
went "thock" rather than squish (well, I can't say that *any* went
"squish").

Now, on sanding or grinding them, they're nearly all dry - but
definitely blistered. Only a few have had a chemical smell to them,
which, because the boat has been on the hard for more than 2 years,
clearly shows that the problem was under the barrier coat in those.
Worse, most of the time, we see prior blue marks from where someone
used a sharpie over the red coat to mark the blister.

Some of these are substantially under the barrier coat - thus the
"thock" when you hit it. Others of them just make a dull sound where
there used to be, all around it, sharp report.

After all that, though, like most blisters, and as Pascoe points out,
it's not a structural issue. It's just "do it right" so we don't have
to do it again. It's a pain in the neck, but the exterior of this boat
will look as new, so we might as well get the bottom while we're donig
it.

When we bought our boat it was 20 years old. The PO had peeled the
bottom and put on 20 coats of epoxy IIRC. When we hauled it for the
survey, the surveyor said there were 'cosmetic' blisters - he pointed
them out to me, and I saw them.

We decided to do nothing.

We've never seen the blisters again.

Resisting the obvious question of haulouts or inspection, I presume you
must be very lucky. Having a blister disappear isn't nearly as common
as having more occur after barrier coating, AFIK.

We bought the boat in 1998. We had it in the water (brackish) through
the 98-99 winter because the marina had no capability for hauling our
size boat. In April 99 we cashed in a boat haul and wash that we won
at the boat show the previous October, and then put it back in the
water where it stayed for that summer.

The following winter (1999-2000), we hauled for the winter. After
that we went down the ICW in the winter two years, and came back in
the spring, hauled and painted the bottom and put the boat back in
again each year. The next time we hauled for the winter was 2002-2003
right after Bob's heart attack.

Bob figured the blisters (which were small - about the size of a
quarter) were incompletely adhered paint and in the outer paint skin
only and they probably wore off. I KNOW I saw them and they are
mentioned in the survey report. (Otherwise Bob might be inclined to
tell me I was delusional.) I know I've never seen them again.


The max we've seen are a couple around the waterline at the edge of
the epoxy coat.

We've always had the boat either red or blue (alternatively), because
we heard that whales don't like black hulled boats or another color
that I can't remember what it is.

Hm. I'd not heard that. The current coat is blue, and Lydia wants to
go back over, once the blisters are repaired, and those spots touched
up, with black. I'm not sure how many whale problems there are in the
Caribbean, so I don't know that it's worth worrying about, but, then
again, the Caribbean, as seen in some of the mailing lists of which I'm
part, may not be so safe for other more political reasons.

So, we're going to fix them all, put blue over all the repairs, and
then put a very heavy application of new ablative, with more on the
waterline and rudder, accompanied by PropSpeed on the running gear,
which is new between the tranny and the prop, dripless packing included
(Thanks, Roger!).

Due to all the repairs which have been done by that time, once all the
repairs have been overcoated after fairing, we'll give a toothcoat
sanding to all of it and then commence to bottom painting while Lydia
does the Poli-Glow. News at 11, so to speak, in my usual voluminous
galleries.

Current project(s) are rewiring the forward bilge pump, relocating and
replumbing the aft bilge pump, and hardpiping the aft head (along with
new supply hose and new cockpit scupper monster hose, all of which
lives under the aft head platform).

Lydia's started her occasional mailing of the news of the day from the
warm-fuzzy side in the google group Flying Pig Log, and I pop into the
yahoogroup The Flying Pig Log less frequently but with more detailed
and technical commentary, for those interested...

L8R

Skip and Lydia, sweltering in the St. Pete Hete

Morgan 461 #2
SV Flying Pig KI4MPC
See our galleries at http://justpickone.org/skip/gallery/
Follow us at

"Believe me, my young friend, there is *nothing*-absolutely
nothing-half
so much worth doing as simply messing, messing-about-in-boats; messing
about in boats-or *with* boats.
In or out of 'em, it doesn't matter. Nothing seems really to matter,
that's the charm of it.
Whether you get away, or whether you don't; whether you arrive at your
destination or whether you reach somewhere else, or whether you never
get anywhere at all, you're always busy, and you never do anything in
particular; and when you've done it there's always something else to
do,
and you can do it if you like, but you'd much better not."