Fiberglassing over wood

[rslifkin]

Originally Posted by Simi 60

Not that leaks should affect a well made composite boat, all ply and end grain would be well sealed, bolt holes would have been drilled oversized, filled with high density glue and re drilled at the smaller size.

Exactly. Unless the leak would be immediately obvious as soon as a tiny bit starts, it shouldn't be causing rot. Plenty of leak points are hidden, so until they're leaking more than a sight seepage, they won't be found.

[armand.seguin]

Hi Coopec43,
I have the book "Covering Wooden Boats with Fiberblass" by Allan H.Vaitses. It was published by International Marine Publishing in 1981. Apparently he did about 50 boats, including some made of steel! I did fish alongside of boats in SE Alaska that had been covered and they were very pleased. I did read the book decades ago but never completed a large project. However, I would not hesitate to cover a boat as the concept is very sound.
One thing he did, which I would surely consider is that while the first layer of matt (not roving first) is still wet, he used a power stapler to staple the cloth to the hull.
One disadvantage of the whole project is that it adds weight. This is not much of a consideration for a displacement hull, since you are also adding substantially to the overall integrity and keeping the water on the outside of the boat. However, for a racing hull this may not be the best answer.
Good luck with the project.

[Benz]

Originally Posted by Jim Cate

IMO, this isn't a design problem nor a material problem. Rather, it is a dereliction of duty on the part of the owner. At the first sign of a leak, the caulking should be renewed, just like any other leak should be repaired. That is what good maintenance is: remediation of defects before any damage is realized.

And the chainplates that are encapsulated in the hull... that you were just lauding... isn't that a great place for unseen crevice corrosion? Like seems to be endemic in Island Packets?

Oh, by the way, our shroud chainplates are indeed through the deck and anchored on plywood based partial bulkheads (more like overgrown knees, actually). When a few drops appeared on one a few years back I immediately renewed the through deck packing and stopped the leak. No soggy, rotting bulkheads here after 30 years of hard usage.

Jim

We have now reached that beautiful moment when everything I've been saying is illustrated. Jim's bulkhead-mounted chainplates developed a leak. If he had not been a vigilant and prudent boat owner; maybe if the leak had developed on the eve of an extended storage period (how many of us store our boats for months on end?), there could easily have been a catastrophe. that catastrophe that Jim averted by being watchful and proactive has caught many and many other boats. So many, in fact, that I feel quite comfortable condemning both the practices of internal chainplates and structural plywood. Your mileage may vary; I have enough mileage to know that this is a common failure point. Why not avoid it in future construction?

[Chotu]

Originally Posted by Benz

We have now reached that beautiful moment when everything I've been saying is illustrated. Jim's bulkhead-mounted chainplates developed a leak. If he had not been a vigilant and prudent boat owner; maybe if the leak had developed on the eve of an extended storage period (how many of us store our boats for months on end?), there could easily have been a catastrophe. that catastrophe that Jim averted by being watchful and proactive has caught many and many other boats. So many, in fact, that I feel quite comfortable condemning both the practices of internal chainplates and structural plywood. Your mileage may vary; I have enough mileage to know that this is a common failure point. Why not avoid it in future construction?

This one I agree with, wood or no wood.

My chain plates aren’t in yet. I have the choice of composite, internal metal going through the deck, or external metal.

My first choice would be composite. However, now that I am allergic to epoxy, that involves hiring someone to do a crucial lamination that I don’t know if they will do correctly. Not something you want to outsource.

This leaves me with metal. I don’t want anything going through the deck that can leak. And I don’t even have any wood over there Near the chain plates. I just don’t like water getting into boats. I like a nice Dusty dry bilge.

So what I will be doing is external metal chain plates.

[coopec43]

Do you have a death wish? (I note you sail a Cape Dory 31. 1981?)

[coopec43]

Originally Posted by Chotu

This one I agree with, wood or no wood.

This leaves me with metal. I don’t want anything going through the deck that can leak. And I don’t even have any wood over there Near the chain plates. I just don’t like water getting into boats. I like a nice Dusty dry bilge.

So what I will be doing is external metal chain plates.

I have something similar to this

[Chotu]

Originally Posted by coopec43

I have something similar to this

Ah, yes. Sorry. That design isn't for me. That’s internal metal chain plates through the deck. I don't like the leak potential. To be fair, that is what most boats have. I have a lot of unique solutions on mine to address all the complaints with boats i’ve developed over the years.

Perfectly valid, but will take some looking after like what Jim talked about above. It will leak. He will have to re-seal it as ongoing maintenance.

[Chotu]

This is the kind I am doing. Just because I am allergic to epoxy and can’t do the composite ones.

This is a metal chain plate external through the hull. So there is no deck penetration to leak.

As usual, the forum is not processing the image EXIF information to put the picture the correct orientation. Left is "up" in this pic.

[Chotu]

And this is the composite chain plate. The best solution of all. Can’t leak, and you could lift the boat up by them.

[coopec43]

Originally Posted by Chotu

Ah, yes. Sorry. That design isn't for me. That’s internal metal chain plates through the deck. I don't like the leak potential. To be fair, that is what most boats have. I have a lot of unique solutions on mine to address all the complaints with boats i’ve developed over the years.

Perfectly valid, but will take some looking after like what Jim talked about above. It will leak. He will have to re-seal it as ongoing maintenance.

That was careless of me. I've had another look and mine are like this but heavier and made of SS

[Benz]

Originally Posted by coopec43

Do you have a death wish? (I note you sail a Cape Dory 31. 1981?)

If this was directed at me (you said Cape Dory but the specs are for Cape George): please note that my Cape George 31 was built by me from a bare hull. So the factory specs for wood bulkheads and core don't apply--I did my own thing. The only way in which my boat resembles the other Cape Georges is in hull shape. Everything else is completely different. Funny thing is, right when I was building mine, the factory owner mentioned that they were no longer doing the wood-cored bulwarks of old: too many boats coming back needing serious repairs. I smiled and continued building my foam-cored bulkheads.

[coopec43]

Originally Posted by Benz

If this was directed at me (you said Cape Dory but the specs are for Cape George): please note that my Cape George 31 was built by me from a bare hull. So the factory specs for wood bulkheads and core don't apply--I did my own thing. The only way in which my boat resembles the other Cape Georges is in hull shape. Everything else is completely different. Funny thing is, right when I was building mine, the factory owner mentioned that they were no longer doing the wood-cored bulwarks of old: too many boats coming back needing serious repairs. I smiled and continued building my foam-cored bulkheads.

Yes if I was building mine again I would use the very latest materials too. But if I maintain my yacht well I'm sure I won't have problems.

[Jim Cate]

Originally Posted by Benz

We have now reached that beautiful moment when everything I've been saying is illustrated. Jim's bulkhead-mounted chainplates developed a leak. If he had not been a vigilant and prudent boat owner; maybe if the leak had developed on the eve of an extended storage period (how many of us store our boats for months on end?), there could easily have been a catastrophe. that catastrophe that Jim averted by being watchful and proactive has caught many and many other boats. So many, in fact, that I feel quite comfortable condemning both the practices of internal chainplates and structural plywood. Your mileage may vary; I have enough mileage to know that this is a common failure point. Why not avoid it in future construction?

Well, perhaps a catastrophe would have occurred, but since the bulkhead is marine ply and is glassed and epoxied, perhaps not.

And by extension, your Cape George's hull is likely built of polyester resin and various forms of glass fiber material. A lot of boats have had issues with osmotic blistering and delamination in that material. In fact I'd bet that far more boats have had such issues than have had rotten bulkheads. Thus, my mileage says one should avoid use of polyester based laminates in hull construction, thus avoiding a common failure point (something we've achieved with our hull construction).

I guess we will have to disagree on this, Benz. There are indeed boats with rotten bulkheads, but there are countless thousands of plywood based bulkheads floating around that are not rotted. It seems to me that what you should condemn is not use of plywood, but poor construction techniques or usage of the plywood. Seems like there are lots of ways to screw up the construction of modern composite bulkheads too... They require a degree of sophistication that exceeds that of good plywood construction IMO. Careful usage is needed with any construction method or material if defects are to be avoided.

Finally, if you eliminate inboard chainplates you condemn boats, especially modern beamy hull shapes, to poor sheeting angles due to shrouds all the way outboard. Not conducive to good upwind performance, that!

Let's hear it for good shipwrights and good designs, no matter what the materials involved, followed by thoughtful maintenance.

Jim

[Benz]

Originally Posted by coopec43

Yes if I was building mine again I would use the very latest materials too. But if I maintain my yacht well I'm sure I won't have problems.

I sincerely hope that you won't (have problems that is).

[Benz]

Originally Posted by Jim Cate

Well, perhaps a catastrophe would have occurred, but since the bulkhead is marine ply and is glassed and epoxied, perhaps not.

And by extension, your Cape George's hull is likely built of polyester resin and various forms of glass fiber material. A lot of boats have had issues with osmotic blistering and delamination in that material. In fact I'd bet that far more boats have had such issues than have had rotten bulkheads. Thus, my mileage says one should avoid use of polyester based laminates in hull construction, thus avoiding a common failure point (something we've achieved with our hull construction).

I guess we will have to disagree on this, Benz. There are indeed boats with rotten bulkheads, but there are countless thousands of plywood based bulkheads floating around that are not rotted. It seems to me that what you should condemn is not use of plywood, but poor construction techniques or usage of the plywood. Seems like there are lots of ways to screw up the construction of modern composite bulkheads too... They require a degree of sophistication that exceeds that of good plywood construction IMO. Careful usage is needed with any construction method or material if defects are to be avoided.

Finally, if you eliminate inboard chainplates you condemn boats, especially modern beamy hull shapes, to poor sheeting angles due to shrouds all the way outboard. Not conducive to good upwind performance, that!

Let's hear it for good shipwrights and good designs, no matter what the materials involved, followed by thoughtful maintenance.

Jim

I can get behind most of this. I was careful to ensure that the builder used Vinylester in the outer layers of hull laminate, so hopefully blisters will not be a problem. Time will tell. I also was careful to use only vinylester resin in the rudder. So far it has stood up well.