Hull Blisters, Treatment of [Master Thread]

[Prairie Schooner]

One of this year’s projects is stripping the bottom to the original surface (gel coat?). I’m scraping off what must be at least two decades of bottom paint in most places. This photo shows the tools I’m finding most useful.


There isn’t a Master Thread on bottom painting or repair as of this writing. This thread seemed to have a wider variety of perspectives so I thought it would be a good place to leave some breadcrumbs. [Moderator's note: This thread now labeled the Master Thread on blister topics]

These are the posts I’ve found helpful:

Bottom paint prep

Will talk to them Monday , but yard has done a lot of sanding of hull to prep for bottom paint which I wasn’t really expecting ( first time I’ve done this as the boat is new to me about 2 1/2 years ) . They showed me a few larger blisters and peeling paint they recommend for repair which I...

ericsonyachts.org

Barrier coat over antifouling!?!?

Hi everyone. Work is progressing on rehabbing our E34-2. One of the projects on my list is redoing the bottom since the antifouling was failing (large chips/flaking). Im using Aqua Strip to do the majority of the job and then plan on sanding the rest to get as fair a surface as I can. But I’m...

ericsonyachts.org

Bottom Job - Revisited

I will be at the yard this weekend to hopefully complete removing the motor from the boat, pull the winches for a service, and just generally clean/organize my work space as I will be starting some of my other projects once the motor is gone. One of my ancillary missions is to visit with the...

ericsonyachts.org

- https://www.interlux.com/en/us/paint-guide/BW058-how-to-fully-repaint-grp-frp
- https://www.interlux.com/en/us/paint-guide/BW057-how-to-fully-repaint-bare-grp-frp

Drying the hull

Over the past year I've been doing a major blister repair job for which I've sought advice under different entries in this forum. I had always heard that one way to deal with blister is to simply dry out the hull. Well, in the process of filling our ground-out blisters we discovered three that...

ericsonyachts.org

Bottom paint failure

Boat - 1983 E30+ in the middle Chesapeake. Timeline: Feb 2014, boat purchased, the broker says "Fresh coat of bottom paint". Doesn't specify what type, but appears some ablative type. March 2016, old dock hand at the junk marina we're at says "Oh, yeah, just sand up what's on there a little...

ericsonyachts.org

E26-2 - Haul-out and Bottom Paint

Sanding, thru-hull removal, rudder repair, fiberglass work, and painting. All the fun I had while hauled out. I bought Sigla bottom-unseen. The previous owner had a rough idea of when it had been out of the water last, but not many details...

ericsonyachts.org

barrier coat issues

The boat was soda blasted last fall; the yard did 3 coats of barrier and VC-17 bottom paint. Lifted the boat off the cradle to place on jack stands to finish the barrier/bottom paint - the straps "peeled" the barrier/bottom paint off in chunks! Not good. Not enough drying time? Question...

ericsonyachts.org

Barrier coat over antifouling!?!?

Hi everyone. Work is progressing on rehabbing our E34-2. One of the projects on my list is redoing the bottom since the antifouling was failing (large chips/flaking). Im using Aqua Strip to do the majority of the job and then plan on sanding the rest to get as fair a surface as I can. But I’m...

ericsonyachts.org

To barrier coat or not to barrier coat?

I am asking for opinions on whether or not it is a bad idea to barrier coat just select areas of the hull before bottom paint. I have repaired a handful of large blisters and don't want to leave the areas around them that are sanded down to gel coat vulnerable to further blistering. However, I...

ericsonyachts.org

Bottom paint on Blister repairs

I pulled my e27 for some early spring work. After 22 months in the water the bottom was generally in excellent shape. I was dumbfounded actually by the good condition. However, in a few places where I made blister repairs in the past, the WM ablative bottom paint wore off down to the epoxy...

ericsonyachts.org

How frequently to paint the bottom, if at all?

Saw a post about bottom paint on another forum - sorry for the wandering eye ;) - and thought I'd ask a question here. We keep our 35-3 in the water year-round. The bottom was last painted in 2020 or 2021 by the previous owner. Was planning to get it repainted next spring, but my diver seems...

ericsonyachts.org

Rule of thumb for cloth, thickened epoxy or just fairing in abundant blister repairs?

We are in the midst of a major hull repair job after finding abundant blisters under the bottom paint on our new-to-us 1982 E38. I posted about this in the fall before we removed the bottom paint. It didn't look quite so bad then. Less than a dozen blisters reached the laminate, and none seemed...

ericsonyachts.org

Blistering - dealbreaker or nah?

I’m looking at a 1980 38 footer for sale. It’s in generally good shape, but there are fairly large blisters on the hull. I’ve read a lot of conflicting opinions on if blisters ever actually a potential structural danger, or merely cosmetic (meaning they don’t penetrate the woven fibers because...

ericsonyachts.org

Need best advice on blister repair

Our 1984 E30+ has been babied for most of her life, and I have kept her in great shape since acquiring her from a discerning owner 11 years ago. I have hauled her every two years, sometimes a bit more often, to check hull, renew bottom paint, etc. She has always had some blisters at the...

ericsonyachts.org

Fairing keel-hull joint

Greetings from Panama, On our Ericson 38, we made some miles and ended up hauling out in Panama, in the middle of a jungle. This is a French operated DIY yard. The long list of our projects include installing a new shaft seal, eliminating rudder play and a new bottom paint. Unfortunately, when...

ericsonyachts.org

Keel smile

Hi everyone, I'm trying to become an Ericson 32-3 owner, I mean I have an accepted offer on a 1985 model but there is an issue with the forward 1/4 of the joint between the ballast keel and the boss/sump it meets with. The joint has a crack from the leading edge back to the first double set of...

ericsonyachts.org

After reading all this, and more, the plan is to sand the rest down, patch any dings/scratches with filled epoxy, fair the keel, apply barrier coat (2-4 coats), then bottom paint. I used Total Boat Total Protect over the transducer and strut work and that seems to have held up well, so that’s what we’ll use for barrier coat. For bottom paint we picked up Micron CSC, black. We’re doing the rudder in white again.

Ambience.

 

[Prairie Schooner]

Fortunately I haven’t come across any medium or big blisters. There are a multitude of small blisters, around 1/8” in diameter. Also fortunate, they all seem to be dry.

A new stripe in gel coat

My 1988 28-2 sits a little low in the water leaving the water line mark a little higher than the white stripe intended as the water line. See photo - you can see the water line mark in the blue. To make it look better I am considering increasing the height of the white stripe by about an inch...

ericsonyachts.org

Why is my bottom paint covering the original boot stripe?

I had my 1984 30+ hauled out for new bottom paint for the first time since I purchased her four years ago. As you can see, her old bottom paint covers her original boot stripe and a new one was painted on. The old paint is a good 4 - 6 inches above the water line. My question is, do I keep it...

ericsonyachts.org

Bootstripe or No Bootstripe?

While we have made the decision, just like to toss it to ya'all to hear your answers. The bootstripe was high at the bow, and low at the back end. I'm taking it off to raise it at the back end (it turns green and slimly in summer) and lower it at the bow, so it is parallel to the waterline...

ericsonyachts.org

Horizontal Baseline ??

Hello All! With OtJ adjusted in her cradle, hanging a plumb bob from the bow and confirming with a laser; I believe I have found the vertical baseline and continued it the length of the hull. The top of the factory applied gelcoat boot stripe is aesthetically curved, but the bottom edge should...

ericsonyachts.org

Cove stripe question

Hi, new to the site. We have a 35-3 that has just been repainted and we are going to have a cove stripe added. We did not get a measurement of the old gold cove stripe, and surprisingly, out of the loads of photos we have, we don't have a great photo depicting the cove stripe. Can anyone help...

ericsonyachts.org

Sheer Line Alternatives

Hello All, Hoping that someone has a suggestion / experience with freshening up the sheer line with either vinyl tape or 3M wrap or ?? Because the sheer line stands proud I am specifically curious about how people are dealing with the bottom edge? Thanks, Mark

ericsonyachts.org

Gelcoat and more at build

Photo is a blister under repair. My understanding is the builder sprays gelcoat into the mold. They get the blue stripe by taping that part off and spraying with gelcoat colored white. Then remove the tape and spray with gelcoat colored blue. Then they layer in the fiberglass to produce the...

ericsonyachts.org

This leads me to believe the white stripe is gelcoat.

My Question is about the white boot stripe. I’d like to be as minimally invasive with it as possible. I’m thinking of just filling any popped blisters with white gel coat and lightly sanding. Is there any reason not to do that? Would you recommend something else? Below the waterline I’ll patch with filled epoxy.

(We’ll consider raising the boot stripe at some point, but for now I just want to get the bottom back to good, original condition.)

Thanks,
Jeff

 

[PANorth]

I’m thinking of just filling any popped blisters with white gel coat and lightly sanding. Is there any reason not to do that? Would you recommend something else? Below the waterline I’ll patch with filled epoxy.

Among the abundance of blisters we repaired over the past couple of years were old repairs of small blisters. It appears that these were filled as you propose. Water had penetrated around many of these. Of course I cannot vouch for methods as it was long before I owned the boat. Perhaps flaring the edges is important.

As an update on our work: We used CopperCoat as "bottom paint". The system, as we applied it, includes two layers of barrier coat (supplied by CopperCoat) and four layers of CopperCoat. The boat has been in the water since November. Repair of a leaking fuel tank kept us from sailing through the PNW winter. But we are refilling the tank today after an epoxy repair and hope to sail in the next couple of weeks for the first time since owning the boat. Yeah!

Below is a picture of the pit corrosion in the tank. There was a clear distinction between the area with corrosion and clean metal. We coated all areas with corrosion with two layers of epoxy. It was all within reach of the port. I'm not a weight lifter so I could fit my arm into the port. We will report on all of this as we put it to use.

 

[peaman]

What a challenging project, to strip the entire bottom. On a 41 foot boat near me, the owner has spent 10 days or more so far, 5-6 hours per day, over the course of a few weeks, with an orbital sander attached to a shop vac, as he works back to a specific prior coat, sometimes lying on his back on a bench as he works around the keel. And then yesterday, the 40 footer next to him had a polyethylene skirt clamped to a plastic sheet ground cover, with a truck bearing signage "Billings Media Blasting" parked alongside, while the crew was rigging hoses to the tent formed under the boat. About 4 hours later (and reportedly $5000), the truck crew was finished blasting ground walnut shells at the bottom, right to the layer requested by the owner.

I hope your project is completed swiftly and to great satisfaction.

 

[Prairie Schooner]

What a challenging project, to strip the entire bottom. On a 41 foot boat near me, the owner has spent 10 days or more so far, 5-6 hours per day, over the course of a few weeks, with an orbital sander attached to a shop vac, as he works back to a specific prior coat, sometimes lying on his back on a bench as he works around the keel. And then yesterday, the 40 footer next to him had a polyethylene skirt clamped to a plastic sheet ground cover, with a truck bearing signage "Billings Media Blasting" parked alongside, while the crew was rigging hoses to the tent formed under the boat. About 4 hours later (and reportedly $5000), the truck crew was finished blasting ground walnut shells at the bottom, right to the layer requested by the owner.

I hope your project is completed swiftly and to great satisfaction.

Thanks Steven.
I've done a fair amount of bottom sanding on friends' boats. I think the scraping is a lot faster. I'm only good for a couple hours at a time, though. We put in a few days last fall and I've been heading to the yard off and on since February. It was cold and blowing stink today so I worked inside the boat. Donna kept suggesting the blasting, but I told her I'd rather spend the money on a spinnaker pole. We'll see if that math works out.

 

[Prairie Schooner]

Among the abundance of blisters we repaired over the past couple of years were old repairs of small blisters. It appears that these were filled as you propose. Water had penetrated around many of these. Of course I cannot vouch for methods as it was long before I owned the boat. Perhaps flaring the edges is important.

As an update on our work: We used CopperCoat as "bottom paint". The system, as we applied it, includes two layers of barrier coat (supplied by CopperCoat) and four layers of CopperCoat. The boat has been in the water since November. Repair of a leaking fuel tank kept us from sailing through the PNW winter. But we are refilling the tank today after an epoxy repair and hope to sail in the next couple of weeks for the first time since owning the boat. Yeah!

Below is a picture of the pit corrosion in the tank. There was a clear distinction between the area with corrosion and clean metal. We coated all areas with corrosion with two layers of epoxy. It was all within reach of the port. I'm not a weight lifter so I could fit my arm into the port. We will report on all of this as we put it to use.

View attachment 49603

Thanks for the feedback, Phil and Amanda.
When you get more info on the tank repair, it would be a great help to the collective wisdom here to document it in a thread. I've been using this one:
- https://ericsonyachts.org/ie/threads/e35-3-replacing-fuel-tank.17731/#post-156979

Jeff

 

[Pete the Cat]

View attachment 49598
One of this year’s projects is stripping the bottom to the original surface (gel coat?). I’m scraping off what must be at least two decades of bottom paint in most places. This photo shows the tools I’m finding most useful.
View attachment 49599

There isn’t a Master Thread on bottom painting or repair as of this writing. This thread seemed to have a wider variety of perspectives so I thought it would be a good place to leave some breadcrumbs. These are the posts I’ve found helpful:

Bottom paint prep

Will talk to them Monday , but yard has done a lot of sanding of hull to prep for bottom paint which I wasn’t really expecting ( first time I’ve done this as the boat is new to me about 2 1/2 years ) . They showed me a few larger blisters and peeling paint they recommend for repair which I...

ericsonyachts.org

Barrier coat over antifouling!?!?

Hi everyone. Work is progressing on rehabbing our E34-2. One of the projects on my list is redoing the bottom since the antifouling was failing (large chips/flaking). Im using Aqua Strip to do the majority of the job and then plan on sanding the rest to get as fair a surface as I can. But I’m...

ericsonyachts.org

Bottom Job - Revisited

I will be at the yard this weekend to hopefully complete removing the motor from the boat, pull the winches for a service, and just generally clean/organize my work space as I will be starting some of my other projects once the motor is gone. One of my ancillary missions is to visit with the...

ericsonyachts.org

- https://www.interlux.com/en/us/paint-guide/BW058-how-to-fully-repaint-grp-frp
- https://www.interlux.com/en/us/paint-guide/BW057-how-to-fully-repaint-bare-grp-frp

Drying the hull

Over the past year I've been doing a major blister repair job for which I've sought advice under different entries in this forum. I had always heard that one way to deal with blister is to simply dry out the hull. Well, in the process of filling our ground-out blisters we discovered three that...

ericsonyachts.org

Bottom paint failure

Boat - 1983 E30+ in the middle Chesapeake. Timeline: Feb 2014, boat purchased, the broker says "Fresh coat of bottom paint". Doesn't specify what type, but appears some ablative type. March 2016, old dock hand at the junk marina we're at says "Oh, yeah, just sand up what's on there a little...

ericsonyachts.org

E26-2 - Haul-out and Bottom Paint

Sanding, thru-hull removal, rudder repair, fiberglass work, and painting. All the fun I had while hauled out. I bought Sigla bottom-unseen. The previous owner had a rough idea of when it had been out of the water last, but not many details...

ericsonyachts.org

barrier coat issues

The boat was soda blasted last fall; the yard did 3 coats of barrier and VC-17 bottom paint. Lifted the boat off the cradle to place on jack stands to finish the barrier/bottom paint - the straps "peeled" the barrier/bottom paint off in chunks! Not good. Not enough drying time? Question...

ericsonyachts.org

Barrier coat over antifouling!?!?

Hi everyone. Work is progressing on rehabbing our E34-2. One of the projects on my list is redoing the bottom since the antifouling was failing (large chips/flaking). Im using Aqua Strip to do the majority of the job and then plan on sanding the rest to get as fair a surface as I can. But I’m...

ericsonyachts.org

To barrier coat or not to barrier coat?

I am asking for opinions on whether or not it is a bad idea to barrier coat just select areas of the hull before bottom paint. I have repaired a handful of large blisters and don't want to leave the areas around them that are sanded down to gel coat vulnerable to further blistering. However, I...

ericsonyachts.org

Bottom paint on Blister repairs

I pulled my e27 for some early spring work. After 22 months in the water the bottom was generally in excellent shape. I was dumbfounded actually by the good condition. However, in a few places where I made blister repairs in the past, the WM ablative bottom paint wore off down to the epoxy...

ericsonyachts.org

How frequently to paint the bottom, if at all?

Saw a post about bottom paint on another forum - sorry for the wandering eye ;) - and thought I'd ask a question here. We keep our 35-3 in the water year-round. The bottom was last painted in 2020 or 2021 by the previous owner. Was planning to get it repainted next spring, but my diver seems...

ericsonyachts.org

Rule of thumb for cloth, thickened epoxy or just fairing in abundant blister repairs?

We are in the midst of a major hull repair job after finding abundant blisters under the bottom paint on our new-to-us 1982 E38. I posted about this in the fall before we removed the bottom paint. It didn't look quite so bad then. Less than a dozen blisters reached the laminate, and none seemed...

ericsonyachts.org

Blistering - dealbreaker or nah?

I’m looking at a 1980 38 footer for sale. It’s in generally good shape, but there are fairly large blisters on the hull. I’ve read a lot of conflicting opinions on if blisters ever actually a potential structural danger, or merely cosmetic (meaning they don’t penetrate the woven fibers because...

ericsonyachts.org

Need best advice on blister repair

Our 1984 E30+ has been babied for most of her life, and I have kept her in great shape since acquiring her from a discerning owner 11 years ago. I have hauled her every two years, sometimes a bit more often, to check hull, renew bottom paint, etc. She has always had some blisters at the...

ericsonyachts.org

Fairing keel-hull joint

Greetings from Panama, On our Ericson 38, we made some miles and ended up hauling out in Panama, in the middle of a jungle. This is a French operated DIY yard. The long list of our projects include installing a new shaft seal, eliminating rudder play and a new bottom paint. Unfortunately, when...

ericsonyachts.org

Keel smile

Hi everyone, I'm trying to become an Ericson 32-3 owner, I mean I have an accepted offer on a 1985 model but there is an issue with the forward 1/4 of the joint between the ballast keel and the boss/sump it meets with. The joint has a crack from the leading edge back to the first double set of...

ericsonyachts.org

After reading all this, and more, the plan is to sand the rest down, patch any dings/scratches with filled epoxy, fair the keel, apply barrier coat (2-4 coats), then bottom paint. I used Total Boat Total Protect over the transducer and strut work and that seems to have held up well, so that’s what we’ll use for barrier coat. For bottom paint we picked up Micron CSC, black. We’re doing the rudder in white again.

Ambience.
View attachment 49600

I would suggest caution with the idea of a barrier coat unless you are going to strip all the gelcoat off and recover with glass. The problem is that your moisture (and this is true of most blisters I have seen) are between the gelcoat and the fiberglass substrate. Unless you give your boat a long period in the hot sun to totally dry, I think you might end up hatching more blisters with the barrier coat (see my experience, read on). I agree with your general approach, but I would not put a barrier coat over gelcoat that has already shown a penchant for bubbling. I pointed out earlier in this thread, I bought a boat that had had a bottom job where a very expensive yard had put a barrier coat over some damp gelcoat and hatched 10,000 blisters. I peeled all the gelcoat off the bottom (Swan and Nautor never put gelcoat on the bottom in the first place because it actually serves no purpose other than to make a cheap smooth surface to paint. I have some blisters on my current Ericson that I will look at when I haul, but unless I think they are attacking the glass beneath (something I have not seen in the yards I have been in), I will likely do nothing.

 

[PANorth]

unless I think they are attacking the glass beneath (something I have not seen in the yards I have been in), I will likely do nothing.

How will you know unless you dig into the blister? We had blisters that had multiple layers of delamination of the fiberglass. We kept going until we hit fiberglass that looked and sounded (tapped) solid. Even then, as described in one of the threads linked above, moisture bubbled up in a few spots when we heated it to apply the first epoxy.

 

[Pete the Cat]

How will you know unless you dig into the blister? We had blisters that had multiple layers of delamination of the fiberglass. We kept going until we hit fiberglass that looked and sounded (tapped) solid. Even then, as described in one of the threads linked above, moisture bubbled up in a few spots when we heated it to apply the first epoxy.

What I thought I saw were many small blisters. I would probably open ones that were larger that a quarter or 50 cent piece. If you had multiple layers of laminate affected on even one of them I would be concerned about the integrity of the layup. I think blisters are more of a symptom than a cause of delamination. But that is just an opinion. The blister problems in the 80s (Valiant, Uniflite) were about a fire retardant mixed in the resin. I believe this started lots of folks believing the gelcoat blisters were an indication of some similar laminate problem in other production boats. I think most boatyards have cooled their blister frenzy. But that is not to say delamination could not happen. Some of the Ericsons were said to oil can and that flexing could cause delamination. As could a resin starved layup that gets worked a bit. I have not seen any boats sink from blisters or localized delamination. Having been a victim of over reaction to the blister crazes of the 80s, I am probably on the other end of the spectrum these days.

 

[Christian Williams]

I once fixed the blisters on a 70s boat merely by putting off fixing them. So I thought.

They can disappear completely as the hull dries out. Impossible to find! Back in the water they reappear overnight.

 

[Prairie Schooner]

I would suggest caution with the idea of a barrier coat unless you are going to strip all the gelcoat off and recover with glass. The problem is that your moisture (and this is true of most blisters I have seen) are between the gelcoat and the fiberglass substrate. Unless you give your boat a long period in the hot sun to totally dry, I think you might end up hatching more blisters with the barrier coat (see my experience, read on). I agree with your general approach, but I would not put a barrier coat over gelcoat that has already shown a penchant for bubbling. I pointed out earlier in this thread, I bought a boat that had had a bottom job where a very expensive yard had put a barrier coat over some damp gelcoat and hatched 10,000 blisters. I peeled all the gelcoat off the bottom (Swan and Nautor never put gelcoat on the bottom in the first place because it actually serves no purpose other than to make a cheap smooth surface to paint. I have some blisters on my current Ericson that I will look at when I haul, but unless I think they are attacking the glass beneath (something I have not seen in the yards I have been in), I will likely do nothing.

Thanks Ray. It's really appealing to be able to cut out the expense and time of barrier coat. I'd just assumed it was standard procedure. I might call Total Boat and see what they say, fully aware they have a vested interest in selling the stuff. It's complicated by an unusually wet spring here, tho the boat has been out of the water since September. I'm continuing to watch responses here before we decide.

 

[Frank Langer]

Thanks Ray. It's really appealing to be able to cut out the expense and time of barrier coat. I'd just assumed it was standard procedure. I might call Total Boat and see what they say, fully aware they have a vested interest in selling the stuff. It's complicated by an unusually wet spring here, tho the boat has been out of the water since September. I'm continuing to watch responses here before we decide.

If you decide to apply a barrier coat, it might be helpful to put a tarp around the hull (taped in place to minimize air escaping) and add an industrial heater for a few days to further dry out the hull. You should be able to rent one at an equipment rental shop.
Frank

 

[Prairie Schooner]

After much vacillating, we’re going to barrier coat the bottom before we bottom paint. What tipped the scale was a chance re-connection with a past acquaintance. He is an industrial chemist with a long career who has spent the last several decades working for a marine resin company. He’s also a former boat owner. I’m leaving the names out in case I’m misrepresenting what he said.

According to him, gel coat formulas from the 70’s - 80’s weren’t dialed in yet. They are porous. Water will get in. This is causing the blisters. He recommended three layers of barrier coat. So, even though it’s costing extra boat buck$$ and time, we’re doing that.

For the white boot stripe, I used a small brush and filled each popped bubble with white barrier coat. Very tedious. Once sanded down, we’ll cover the entire stripe with white barrier coat.




The keel was stripped to bare metal and barrier coated. The seam joint was filled with Thixo flexible epoxy.* Then it was faired with TB epoxy fairing compound, and will be covered with barrier coat.



*If you buy Thixo, definitely get an extra thrust caulk gun. My regular gun required way too much hand pressure and still only pumped a trickle. The 'SolidWork Professional Caulk Gun with Ergonomic Steel Handle, for 10 oz Cartridge, Adjustable 24:1 Thrust Ratio' worked well for me. Also, Total Boat doesn’t sell extra nozzles, but the West Six-10 static mixing nozzles fit, if the two TB supplies isn't enough.

 

[Prairie Schooner]

I very much appreciate everyone who's shared their experience. It's all valid. There are so many variables. After weighing it all, we're taking this route in the great boat ownership experiment. One thing we're not able to do is make a tent and dry the hull out further. We've had rain at least once a week all spring. That may come back to bite us in the transom. But, the boat has been on land since September. Not being immersed is a big thing, I think. I'll report on how it all works out.


We'd left some patches of thin old bottom paint since Micron CSC could go over that. The new plan meant we had to take off anything thick enough to still be ablative. What is left only amounts to what I consider 'staining'. The gray patch is where I rebedded the strut. We paint the rudder white and will give that the full strip treatment another year.

Today is painting day.

 

[Pete the Cat]

I very much appreciate everyone who's shared their experience. It's all valid. There are so many variables. After weighing it all, we're taking this route in the great boat ownership experiment. One thing we're not able to do is make a tent and dry the hull out further. We've had rain at least once a week all spring. That may come back to bite us in the transom. But, the boat has been on land since September. Not being immersed is a big thing, I think. I'll report on how it all works out.

View attachment 49957
We'd left some patches of thin old bottom paint since Micron CSC could go over that. The new plan meant we had to take off anything thick enough to still be ablative. What is left only amounts to what I consider 'staining'. The gray patch is where I rebedded the strut. We paint the rudder white and will give that the full strip treatment another year.
View attachment 49958
Today is painting day.

I am sure you have everything timed correctly. The guys at my yard have a particular timing of barrier coats and generally want to put the first actual bottom coat on ASAP per the directions so that it binds with the barrier coat. Every different layer on the bottom creates a possibility for small, probably only esthetic, blisters. While I disagree with your consultant: I worked in boatyards in the 70s and 80s and I really question the question about the gelcoat formulas changing, but he is right to say that it is very porous (so why would you put some thing "impenetrable" over something porous?) but West Systems guys were blaming gelcoat guys, the gelcoat guys were blaming the glassmen and West Systems folks (they had the big guns back then) and boatyards were blaming both and boatowners were paying the bills. There was a period where everyone decided that all the blister moisture was coming from inside the boat! There are opinion everywhere and mine is just one. I think you will be fine with what you are doing if you have the hull reasonably dry. Looks like you have done a good prep job and being out of the water as long as you have is a real plus for avoiding problems I have seen.

 

[Prairie Schooner]

I am sure you have everything timed correctly. The guys at my yard have a particular timing of barrier coats and generally want to put the first actual bottom coat on ASAP per the directions so that it binds with the barrier coat. Every different layer on the bottom creates a possibility for small, probably only esthetic, blisters. While I disagree with your consultant: I worked in boatyards in the 70s and 80s and I really question the question about the gelcoat formulas changing, but he is right to say that it is very porous (so why would you put some thing "impenetrable" over something porous?) but West Systems guys were blaming gelcoat guys, the gelcoat guys were blaming the glassmen and West Systems folks (they had the big guns back then) and boatyards were blaming both and boatowners were paying the bills. There was a period where everyone decided that all the blister moisture was coming from inside the boat! There are opinion everywhere and mine is just one. I think you will be fine with what you are doing if you have the hull reasonably dry. Looks like you have done a good prep job and being out of the water as long as you have is a real plus for avoiding problems I have seen.

I hope I don't sound like I'm saying I'm categorically right and any other view is absolutely wrong. This subject is a crazier rabbit hole than a lot of other boat maintenance issues. This was the decision we made, but I see it more as an experiment than anything.

 

[Pete the Cat]

I have been a boatyard worker at launch time on the East Coast for quite a few years--they always need some old guys to trouble shoot the boats so that the frenzy to get them all splashed does not get delayed by one problem. Most yards have a line at the Travellft from May1 to July 4--it is madness with the weather and tides our enemy. I have seen a lot of the same boats annually and watched their bottoms. I have come to think that spontaneous blistering is not nearly as common as yard folks tried to sell to boatowners back in the 90s when they were hawking peel and barrier coat treatments. But I think the rumor and mythology has continued, and boatyards are loathe to turn down work they can do off season to keep the guys employed during the down season. I really liked Nautor's idea way back when, that less is more; they sold their very well built boats with bare fiberglass bottoms--no gelcoat below the waterline--and cautioned folks to carefully apply bottom paint per the directions. So what, exactly, are we trying to protect with a barrier coat? But I have seem lots of coatings done that I was skeptical of, and very few had real problems. The blister fears are all overstated imho both in potential of occurrence and seriousness as a threat to the integrity of your vessel. Do whatever you want. Go sailing and don't think about it.

 

[Christian Williams]

And it's expensive. The cost for my boat in 2015 was $15,000--an invoice the previous owner said he framed.

...

 

[Pete the Cat]

And it's expensive. The cost for my boat in 2015 was $15,000--an invoice the previous owner said he framed.

View attachment 49986...View attachment 49987

I wasted $14,000 of materials (and just a bit of that was labor for the peeling) on the same project on my Tartan and about 4 months of my labor laying up a new fiberglass bottom. That was an expensive education about blister mythology in 1994. In retrospect, it was caused by a poorly installed blister coat by the PO of the boat and I over reacted to the crop of 10,000 blisters his expensive intervention cost. Good for the boatyards. Not so much for the boat owners. Unless the lens distorts the hull shape in the second picture, it is interesting about how the 38 seems to have very round proportions. Might be the camera angle.

 

[Christian Williams]

Previous owner photo, probably with early phone. I find that the shooting angle, or lens choice, really bolloxes up memory, or reality, although who knows which is which. Here's a more recent GoPro shot, with wide-angle distortion as evidenced by the Travelift legs.