Blisters and Pocking, Oh My!

[RBEmerson]

Long story short, Peter Hartoft did a bottom survey on Monday afternoon. Moisture was only "moderate" and consistent with a boat being in the water for two years and then spending the last two and a half winter months on the hard (most of the drying happens when it warms up).

Basically, someone put the Bar-Rust over a layer of bottom paint(!) and another layer of epoxy or barrier coat of some sort. The osmotic blistering is still there, of course.

The recommendation was to, in effect, do nothing or burn at least $13K (based on about $350/ft) on a blister job. The "do nothing" plan involves sanding down the pocked bits, putting on a couple of coats of hard bottom paint (for filler), dressing the surface, and putting on 2-3 coats of soft ablative paint. Adding any sort of barrier coat was specifically not recommended as it would only lock in existing moisture wear or fail in 2-3 years anyway.

As we don't foresee selling the boat any time soon, we'll take the easy answer.

While I'm at it, I have to say that the time spent with Peter was very instructive. We spent a little time checking out some other issues and I learned a number of useful things in the process. Peter Hartoft... two thumbs up!

[bobfnbw]

Haven't had t do one yet, but the $350 bucks a foot seems like a joke to me. As in all boat projects, it depends on who does the work. You can pay someone to do it and maybe it gets done right, maybe not, either waty your out a lot of cash, OR you can do it yourself, and even if you don't do the best job, you did it yourself, learned alot, and just maybe did it better than a "professional" would have.

I have a lot of small blisters and plan on doing the job myself when I can, maybe in 2010. In the meantime its not bothering me so I figure why bother them?

[Pblais]

Haven't had t do one yet, but the $350 bucks a foot seems like a joke to me. As in all boat projects, it depends on who does the work.

By the foot pricing is pretty common in estimating. It works better than you might think as a rule of thumb. Obviously you look at the specific job and adjust the estimate from there. Estimating metrics are actually pretty good but no way perfect. They do make assumptions that you won't make a mistake or screw it up along the way. If you needed to bid the job it's how you would do it in a way that is quick and close to accurate.

I have a lot of small blisters and plan on doing the job myself when I can, maybe in 2010. In the meantime its not bothering me so I figure why bother them?

You'll never sink the boat because it had blisters. They don't get worse overnight either. A guy in our club did his 37 ft Tartan all himself. It took a season. He was a life long sailor, retired engineer, and not employed. It just takes a lot of time that wears you out when you are not 25 years old. Arms, shoulders, back, and knees get a work out.

[RBEmerson]

The $350/ft number is a reflection of current "done by a pro" prices for the Annapolis, MD area. Obviously, DIY can change this significantly.

[westsail42]

Originally Posted by bobfnbw

I have a lot of small blisters and plan on doing the job myself when I can, maybe in 2010. In the meantime its not bothering me so I figure why bother them?

Unless you have access to a gelcoat peeler I would NOT recommend DIY. If you tent, sand and grind, it will be tough to get a consistent depth on the removal.

Not sure how much gelcoat peelers cost, but I bet they aint cheap.

[RBEmerson]

In my previous post, I started to comment on DIY and then deleted it before posting. But since you've opened the door...

+1 on the peeler. Of course, one can get a Dremel grinder and clean everything out, blister by blister, hoping to get them all. But, of course, that won't happen (just the nature of the beast). Then there's all the time with a fairing board...

A friend went that route on a small PS (Dana?) and then found out the epoxy mix he'd used hadn't cured worth a hoot and had to grub it all out to do the job all over.

[westsail42]

Yeah, seeing the pro's with those gelcoat peelers is pretty slick. You can dial in the precise depth. It will remove the bottom paint, gelcoat and glass all in one pass. Connect it to a large shop vac to collect everything. No tent required. Keeps the Dept of Ecology happy too.

[bobfnbw]

As I mentioned, haven't done it yet, so don't know much about gelcoat peelers.
But have been around enough boatyards to see it being done the old fashioned way of grinding it out.
I understand it would be a tough job. But I can't spend that much money to repair something that for the most part is largely cosmetic. Even if you do a half assed job with a grinder, on a cruising boat no one will care, except when it comes time to sell maybe, and a savy buyer will perhaps know that gelcoat blisters on older and somethimes newer boats are the nature of the beast.
You can go with steel, but then there is rust to deal with.
You can go with aluminum, if you can afford it.
You can go with wood, but their are problems there as well, more than a few or even a lot of blisters will be.
Or go with plastic and have a some cosmetic pox. From what I understand rarely will blisters case a structural problem.

The problem is finding a boat yard where you can do the work yourself. They are getting harder and harder to find.

But a festool sander hooked up to a festool vac and enough time should do a adequate job, given enough time. No ?

[bobfnbw]

Originally Posted by Pblais

By the foot pricing is pretty common in estimating.

It just takes a lot of time that wears you out when you are not 25 years old. Arms, shoulders, back, and knees get a work out.

Paul sorry didn't mean to sound like the joke was in the by the foot estimating. Guess they have to use some way of estimating a job.

My point was the cost of it. 13K to strip the hull of a small boat seems crazy to me. But then i'm cheap

And just think of how good my arms and shoulders will look after months of grinding and sanding .... not to mention the tan lines around the dust mask lines... lol.

[RBEmerson]

It depends on what you want to accomplish. If the goal is to pop all the pimples on the hull and fill them in, sure, a grinder, dabs of filler, and a lot of time sanding followed by some epoxy coats will do a passable job.

But... all you've done is to cure the obvious blisters and seal up the ones you couldn't see or find, leaving them to slowly continue to grow. Until you'll see bulges in the bottom paint and epoxy and start the job all over again.

Or you can get the hull properly assessed to determine how far in the moisture has gone and remove all of it, replace the stripped material with the proper materials (both the actual fiberglass and the resins) applied properly (ambient conditions make a big difference in how to mix and apply resins and glass), coated properly (dealing with stuff like amine blush means neutralizing the coating or seeing the subsequent coats fail). The room for surprises isn't inconsiderable.

You pick it.

[Pblais]

And just think of how good my arms and shoulders will look after months of grinding and sanding .... not to mention the tan lines around the dust mask lines... lol.

Call it a $13,000 adventure - no expenses paid. It clearly is a big job. You could do it the old fashioned way. This isn't a technical challenge. You can learn to mix epoxy without setting it on fire. Just buy a trunk load of those little plastic cups. By the time the job is done you'll know everyone in the boat yard and a few dozen bystanders from just watching. Many life experiences that are cheap are worth it.

"So when do you think you'll be done"

[bobfnbw]

Good points to all of you. Thoughts to consider.

[Stevens 47]

I have a gel-plane that I purchased to peel my bottom...worked great. It took me about 2 days on my boat. I am going to splash the boat this summer so I will be looking to sell the plane. PM me if you are interested.