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R. Caffery
08-01-2003, 05:19 PM
Can adhesives like 3-M 5200 be used it construction of a cedar planked hull instead of traditional caulking between planks?

Can a cedar planked hull (new construction) be successfully sheathed in epoxy and 6 oz. cloth without problems developing?

Note: I am referring to a traditional cedar planked hull not a cold molded hull. I would also appreciate any comments on the use of "treated" southern yellow pine like "Osmose" brand for hull smile.gif framing material. Thanks.

R. Caffery
08-01-2003, 05:19 PM
Can adhesives like 3-M 5200 be used it construction of a cedar planked hull instead of traditional caulking between planks?

Can a cedar planked hull (new construction) be successfully sheathed in epoxy and 6 oz. cloth without problems developing?

Note: I am referring to a traditional cedar planked hull not a cold molded hull. I would also appreciate any comments on the use of "treated" southern yellow pine like "Osmose" brand for hull smile.gif framing material. Thanks.

R. Caffery
08-01-2003, 05:19 PM
Can adhesives like 3-M 5200 be used it construction of a cedar planked hull instead of traditional caulking between planks?

Can a cedar planked hull (new construction) be successfully sheathed in epoxy and 6 oz. cloth without problems developing?

Note: I am referring to a traditional cedar planked hull not a cold molded hull. I would also appreciate any comments on the use of "treated" southern yellow pine like "Osmose" brand for hull smile.gif framing material. Thanks.

Scott Rosen
08-01-2003, 05:39 PM
I imagine you'll get a lot of comments on this.

You should not use any kind of goo in a tube as a substitute for the cotton caulking. The cotton is a structural part of carvel hull construction. If you want to use goo as a seam compound over the cotton, you could . . . but not 5200. Do a Forum search on caulking and you'll find tons of stuff.

Why on earth would you want to go through the trouble of building a carvel hull and then sheathing it in 'poxy and 'glass? The two hull systems would be working against each other and could cause failures in both.

I think folks have used Southern Yellow Pine for planking and framing with good results. Don't know about the treated part . . .

Scott Rosen
08-01-2003, 05:39 PM
I imagine you'll get a lot of comments on this.

You should not use any kind of goo in a tube as a substitute for the cotton caulking. The cotton is a structural part of carvel hull construction. If you want to use goo as a seam compound over the cotton, you could . . . but not 5200. Do a Forum search on caulking and you'll find tons of stuff.

Why on earth would you want to go through the trouble of building a carvel hull and then sheathing it in 'poxy and 'glass? The two hull systems would be working against each other and could cause failures in both.

I think folks have used Southern Yellow Pine for planking and framing with good results. Don't know about the treated part . . .

Scott Rosen
08-01-2003, 05:39 PM
I imagine you'll get a lot of comments on this.

You should not use any kind of goo in a tube as a substitute for the cotton caulking. The cotton is a structural part of carvel hull construction. If you want to use goo as a seam compound over the cotton, you could . . . but not 5200. Do a Forum search on caulking and you'll find tons of stuff.

Why on earth would you want to go through the trouble of building a carvel hull and then sheathing it in 'poxy and 'glass? The two hull systems would be working against each other and could cause failures in both.

I think folks have used Southern Yellow Pine for planking and framing with good results. Don't know about the treated part . . .

Hughman
08-01-2003, 10:12 PM
Cleek? you there, Cleek?

Hughman
08-01-2003, 10:12 PM
Cleek? you there, Cleek?

Hughman
08-01-2003, 10:12 PM
Cleek? you there, Cleek?

Wiley Baggins
08-01-2003, 10:42 PM
Hmmm...I'm no Cleek (or Dave Fleming), but I'll pitch in here while you wait for your trip to the woodshed. ;)

With regard to the 3M-5200 in lieu of caulking, a Phil Bolger design (SHIVAREE) was built lapstrake with 3M-5200 between the laps, but I believe that the planking may have been ply and the boat frameless. I also believe that Bolger wasn't entirely happy with this method. You may be less thrilled with the application that you are proposing, but maybe it's been tried successfully.

With regard to sheathing a traditional hull, especially a new hull, I don't see the benefit. What purpose do you feel the sheathing will serve?

Wiley Baggins
08-01-2003, 10:42 PM
Hmmm...I'm no Cleek (or Dave Fleming), but I'll pitch in here while you wait for your trip to the woodshed. ;)

With regard to the 3M-5200 in lieu of caulking, a Phil Bolger design (SHIVAREE) was built lapstrake with 3M-5200 between the laps, but I believe that the planking may have been ply and the boat frameless. I also believe that Bolger wasn't entirely happy with this method. You may be less thrilled with the application that you are proposing, but maybe it's been tried successfully.

With regard to sheathing a traditional hull, especially a new hull, I don't see the benefit. What purpose do you feel the sheathing will serve?

Wiley Baggins
08-01-2003, 10:42 PM
Hmmm...I'm no Cleek (or Dave Fleming), but I'll pitch in here while you wait for your trip to the woodshed. ;)

With regard to the 3M-5200 in lieu of caulking, a Phil Bolger design (SHIVAREE) was built lapstrake with 3M-5200 between the laps, but I believe that the planking may have been ply and the boat frameless. I also believe that Bolger wasn't entirely happy with this method. You may be less thrilled with the application that you are proposing, but maybe it's been tried successfully.

With regard to sheathing a traditional hull, especially a new hull, I don't see the benefit. What purpose do you feel the sheathing will serve?

bainbridgeisland
08-02-2003, 08:28 AM
Using 3M 5200 is not recommended for carvel planking. There is a good practical reason for this. Glue is most effective when loaded mostly in shear. For 3m 5200, shear strength is about 1,200 pounds per square inch whereas peel strength is about 40 pounds per linear inch.

To demonstrate what shear is, put the palms of your hands together firmly and rub your hands vigorously. The résistance of your palms to sliding simulates shear loading. Good glue joints are always loaded in this direction.

Glue is very poor in peel loading. An example of peel load would be the feel of an adhesive band-aid when peeled off.

The calking between planks accommodates movement as the planks change moisture content and change size with temperature variation. The caulking is sort of like a spring loaded stopper, the resilience of the wood providing the spring. Also, the rigidity of the hull is dependent on the firmness of the caulking. The caulking helps keep the planks from sliding along each other as the boat twists over waves.

An adhesive does not provide enough bond between the planking. This is because most of the adhesive load in the planking would be in the peel direction. Also, 3m 5200 is not rigid enough to help the rigidity of the hull.

Sheathing on carvel planked hulls is not recommended for a number of reasons. I think the most important is that the rigidity of epoxy - glass is very different than timber. Thus as the wood changes shape with temperature and humidity, the stiffer epoxy - glass is very highly loaded. This causes the glass to break or come un-bonded from the timber.

Cedar is very rot resistant. With minimum care cedar planking should last more than 50 years. So why even consider 3m 5200 or epoxy - glass?

[QUOTE]Originally posted by R. Caffery:
[QB]Can adhesives like 3-M 5200 be used it construction of a cedar planked hull instead of traditional caulking between planks?

Can a cedar planked hull (new construction) be successfully sheathed in epoxy and 6 oz. cloth without problems developing?

bainbridgeisland
08-02-2003, 08:28 AM
Using 3M 5200 is not recommended for carvel planking. There is a good practical reason for this. Glue is most effective when loaded mostly in shear. For 3m 5200, shear strength is about 1,200 pounds per square inch whereas peel strength is about 40 pounds per linear inch.

To demonstrate what shear is, put the palms of your hands together firmly and rub your hands vigorously. The résistance of your palms to sliding simulates shear loading. Good glue joints are always loaded in this direction.

Glue is very poor in peel loading. An example of peel load would be the feel of an adhesive band-aid when peeled off.

The calking between planks accommodates movement as the planks change moisture content and change size with temperature variation. The caulking is sort of like a spring loaded stopper, the resilience of the wood providing the spring. Also, the rigidity of the hull is dependent on the firmness of the caulking. The caulking helps keep the planks from sliding along each other as the boat twists over waves.

An adhesive does not provide enough bond between the planking. This is because most of the adhesive load in the planking would be in the peel direction. Also, 3m 5200 is not rigid enough to help the rigidity of the hull.

Sheathing on carvel planked hulls is not recommended for a number of reasons. I think the most important is that the rigidity of epoxy - glass is very different than timber. Thus as the wood changes shape with temperature and humidity, the stiffer epoxy - glass is very highly loaded. This causes the glass to break or come un-bonded from the timber.

Cedar is very rot resistant. With minimum care cedar planking should last more than 50 years. So why even consider 3m 5200 or epoxy - glass?

[QUOTE]Originally posted by R. Caffery:
[QB]Can adhesives like 3-M 5200 be used it construction of a cedar planked hull instead of traditional caulking between planks?

Can a cedar planked hull (new construction) be successfully sheathed in epoxy and 6 oz. cloth without problems developing?

bainbridgeisland
08-02-2003, 08:28 AM
Using 3M 5200 is not recommended for carvel planking. There is a good practical reason for this. Glue is most effective when loaded mostly in shear. For 3m 5200, shear strength is about 1,200 pounds per square inch whereas peel strength is about 40 pounds per linear inch.

To demonstrate what shear is, put the palms of your hands together firmly and rub your hands vigorously. The résistance of your palms to sliding simulates shear loading. Good glue joints are always loaded in this direction.

Glue is very poor in peel loading. An example of peel load would be the feel of an adhesive band-aid when peeled off.

The calking between planks accommodates movement as the planks change moisture content and change size with temperature variation. The caulking is sort of like a spring loaded stopper, the resilience of the wood providing the spring. Also, the rigidity of the hull is dependent on the firmness of the caulking. The caulking helps keep the planks from sliding along each other as the boat twists over waves.

An adhesive does not provide enough bond between the planking. This is because most of the adhesive load in the planking would be in the peel direction. Also, 3m 5200 is not rigid enough to help the rigidity of the hull.

Sheathing on carvel planked hulls is not recommended for a number of reasons. I think the most important is that the rigidity of epoxy - glass is very different than timber. Thus as the wood changes shape with temperature and humidity, the stiffer epoxy - glass is very highly loaded. This causes the glass to break or come un-bonded from the timber.

Cedar is very rot resistant. With minimum care cedar planking should last more than 50 years. So why even consider 3m 5200 or epoxy - glass?

[QUOTE]Originally posted by R. Caffery:
[QB]Can adhesives like 3-M 5200 be used it construction of a cedar planked hull instead of traditional caulking between planks?

Can a cedar planked hull (new construction) be successfully sheathed in epoxy and 6 oz. cloth without problems developing?

NormMessinger
08-02-2003, 09:37 AM
Cleek wouldn't have been so gentle. Where you been Bainbridge? Off having fun I hope.

NormMessinger
08-02-2003, 09:37 AM
Cleek wouldn't have been so gentle. Where you been Bainbridge? Off having fun I hope.

NormMessinger
08-02-2003, 09:37 AM
Cleek wouldn't have been so gentle. Where you been Bainbridge? Off having fun I hope.

R. Caffery
08-02-2003, 05:38 PM
Gentlemen, the questions asked indeed indicate a total lack of knowledge on my part on the subject of planked hull construction.

Here's the dilemna:

The builder has experience with carvel, but his boats generally stay in the water after launch. My desire to haul the boat on a trailer means wet/dry cycles which may not be the best situation for a traditional carvel planked hull.

The comments sound like my solution of sheathing the hull is not a great idea. Should I ditch this plan and go with a plywood boat design instead?

Thanks, I appreciate helpful incite.

R. Caffery
08-02-2003, 05:38 PM
Gentlemen, the questions asked indeed indicate a total lack of knowledge on my part on the subject of planked hull construction.

Here's the dilemna:

The builder has experience with carvel, but his boats generally stay in the water after launch. My desire to haul the boat on a trailer means wet/dry cycles which may not be the best situation for a traditional carvel planked hull.

The comments sound like my solution of sheathing the hull is not a great idea. Should I ditch this plan and go with a plywood boat design instead?

Thanks, I appreciate helpful incite.

R. Caffery
08-02-2003, 05:38 PM
Gentlemen, the questions asked indeed indicate a total lack of knowledge on my part on the subject of planked hull construction.

Here's the dilemna:

The builder has experience with carvel, but his boats generally stay in the water after launch. My desire to haul the boat on a trailer means wet/dry cycles which may not be the best situation for a traditional carvel planked hull.

The comments sound like my solution of sheathing the hull is not a great idea. Should I ditch this plan and go with a plywood boat design instead?

Thanks, I appreciate helpful incite.

bainbridgeisland
08-02-2003, 06:46 PM
A plywood boat would work for you.

Another alternative is lapstrake planking. It will stay tight while out of the water. Solid timber riveted over steam bent frames is traditional, good looking and will stay tight.

Another alternative is glued lapstrake plywood. This has been around at least since the 1950s. It will also stay tight while the boat is out of the water.

Strip planking would also be suitable. Though not as traditional as carvel or lapstrake, it has been used since before the 1940s. Again, this method can produce a boat that stays tight when out of the water.

[ 08-03-2003, 06:56 PM: Message edited by: bainbridgeisland ]

bainbridgeisland
08-02-2003, 06:46 PM
A plywood boat would work for you.

Another alternative is lapstrake planking. It will stay tight while out of the water. Solid timber riveted over steam bent frames is traditional, good looking and will stay tight.

Another alternative is glued lapstrake plywood. This has been around at least since the 1950s. It will also stay tight while the boat is out of the water.

Strip planking would also be suitable. Though not as traditional as carvel or lapstrake, it has been used since before the 1940s. Again, this method can produce a boat that stays tight when out of the water.

[ 08-03-2003, 06:56 PM: Message edited by: bainbridgeisland ]

bainbridgeisland
08-02-2003, 06:46 PM
A plywood boat would work for you.

Another alternative is lapstrake planking. It will stay tight while out of the water. Solid timber riveted over steam bent frames is traditional, good looking and will stay tight.

Another alternative is glued lapstrake plywood. This has been around at least since the 1950s. It will also stay tight while the boat is out of the water.

Strip planking would also be suitable. Though not as traditional as carvel or lapstrake, it has been used since before the 1940s. Again, this method can produce a boat that stays tight when out of the water.

[ 08-03-2003, 06:56 PM: Message edited by: bainbridgeisland ]

Scott Rosen
08-03-2003, 07:16 AM
Plywood or cold-molded would be the best ways to build a dry-sailed boat. Plywood lap is a great option, too.

Scott Rosen
08-03-2003, 07:16 AM
Plywood or cold-molded would be the best ways to build a dry-sailed boat. Plywood lap is a great option, too.

Scott Rosen
08-03-2003, 07:16 AM
Plywood or cold-molded would be the best ways to build a dry-sailed boat. Plywood lap is a great option, too.

Venchka
08-04-2003, 12:01 AM
Russell,

HELLO! Wayne in Belle Chasse here, by way of Lafayette, many many moons ago. I was driving through Lafayette about 6 hours ago.

What type of boat do you want & who's the builder you're talking to? I beat the bushes last year and didn't have much luck finding a builder in South Lousiana unless I wanted an aluminum boat.

I had the same needs too-the boat will live on a trailer most of it's life. I opted for glued lap plywood but the other methods mentioned above work well also.

My boat and I might be in Lafayette the first week of September, and if the timing is good, I'd be happy to let you take a look at her.

Venchka
08-04-2003, 12:01 AM
Russell,

HELLO! Wayne in Belle Chasse here, by way of Lafayette, many many moons ago. I was driving through Lafayette about 6 hours ago.

What type of boat do you want & who's the builder you're talking to? I beat the bushes last year and didn't have much luck finding a builder in South Lousiana unless I wanted an aluminum boat.

I had the same needs too-the boat will live on a trailer most of it's life. I opted for glued lap plywood but the other methods mentioned above work well also.

My boat and I might be in Lafayette the first week of September, and if the timing is good, I'd be happy to let you take a look at her.

Venchka
08-04-2003, 12:01 AM
Russell,

HELLO! Wayne in Belle Chasse here, by way of Lafayette, many many moons ago. I was driving through Lafayette about 6 hours ago.

What type of boat do you want & who's the builder you're talking to? I beat the bushes last year and didn't have much luck finding a builder in South Lousiana unless I wanted an aluminum boat.

I had the same needs too-the boat will live on a trailer most of it's life. I opted for glued lap plywood but the other methods mentioned above work well also.

My boat and I might be in Lafayette the first week of September, and if the timing is good, I'd be happy to let you take a look at her.

R. Caffery
08-04-2003, 12:55 PM
Thanks to all for the replies.

Wayne, the builder is in Dulac, La. and is the son of the late "Moot" Billiot who built a plywood skiff for me 12 years ago. Still a good boat, but "Moot" was not fond of plywood, all his work was cypress planked hulls, and the result was not his best work, even though it ended up being very durable and reflects the design of boats in that area.

His son Joseph and I have discussed the project and he seems much more at ease with plywood construction, even though I may test his skills and ask him to plank the sides in the lapstrake fashion as late Capt. Jim Orrel's "Lapstrake Express 22" (a Bolger design?)is constructed.

Question: Why use plywood for the lap planks, over natural planking, is this a weight or structural integrity issue? The only marine plywood available in this area is fir and I swore I would never plank the sides of a hull with it again, no matter how well you fair and prep it, paint jobs don't last with the checking and cracking.

My amateur solution is a plan to require frames every 18" and use plywood for the first plank, glass the bottom and this plank, then plank with spanish cedar.

R. Caffery
08-04-2003, 12:55 PM
Thanks to all for the replies.

Wayne, the builder is in Dulac, La. and is the son of the late "Moot" Billiot who built a plywood skiff for me 12 years ago. Still a good boat, but "Moot" was not fond of plywood, all his work was cypress planked hulls, and the result was not his best work, even though it ended up being very durable and reflects the design of boats in that area.

His son Joseph and I have discussed the project and he seems much more at ease with plywood construction, even though I may test his skills and ask him to plank the sides in the lapstrake fashion as late Capt. Jim Orrel's "Lapstrake Express 22" (a Bolger design?)is constructed.

Question: Why use plywood for the lap planks, over natural planking, is this a weight or structural integrity issue? The only marine plywood available in this area is fir and I swore I would never plank the sides of a hull with it again, no matter how well you fair and prep it, paint jobs don't last with the checking and cracking.

My amateur solution is a plan to require frames every 18" and use plywood for the first plank, glass the bottom and this plank, then plank with spanish cedar.

R. Caffery
08-04-2003, 12:55 PM
Thanks to all for the replies.

Wayne, the builder is in Dulac, La. and is the son of the late "Moot" Billiot who built a plywood skiff for me 12 years ago. Still a good boat, but "Moot" was not fond of plywood, all his work was cypress planked hulls, and the result was not his best work, even though it ended up being very durable and reflects the design of boats in that area.

His son Joseph and I have discussed the project and he seems much more at ease with plywood construction, even though I may test his skills and ask him to plank the sides in the lapstrake fashion as late Capt. Jim Orrel's "Lapstrake Express 22" (a Bolger design?)is constructed.

Question: Why use plywood for the lap planks, over natural planking, is this a weight or structural integrity issue? The only marine plywood available in this area is fir and I swore I would never plank the sides of a hull with it again, no matter how well you fair and prep it, paint jobs don't last with the checking and cracking.

My amateur solution is a plan to require frames every 18" and use plywood for the first plank, glass the bottom and this plank, then plank with spanish cedar.

Venchka
08-04-2003, 10:24 PM
The builder lives in Dulac. He learned from his father. Likes to work with real boards for planking.

Hmmmmm...

Sinker cypress. Varnished. Only thing to use. Now, all you need is a design that can be planked with good sinker cypress.

You really haven't told us what you have in mind as far as the boat's use is concerned or the type of design you are considering.

Amen on the douglas-fir plywood. I found a lovely little spit ketch for sail in Jesuit Bend. It was built out of fir and looked like old crazed porcelin. If you want marine plywood-the good stuff-order from M.L. Condon or Harbor Sales. Figure about $300 frieght for 300-500 pounds of plywood. Actually, if you know anyone in Baton Rouge, you can save a bundle by not paying the "west of the Mississippi" price.

Venchka
08-04-2003, 10:24 PM
The builder lives in Dulac. He learned from his father. Likes to work with real boards for planking.

Hmmmmm...

Sinker cypress. Varnished. Only thing to use. Now, all you need is a design that can be planked with good sinker cypress.

You really haven't told us what you have in mind as far as the boat's use is concerned or the type of design you are considering.

Amen on the douglas-fir plywood. I found a lovely little spit ketch for sail in Jesuit Bend. It was built out of fir and looked like old crazed porcelin. If you want marine plywood-the good stuff-order from M.L. Condon or Harbor Sales. Figure about $300 frieght for 300-500 pounds of plywood. Actually, if you know anyone in Baton Rouge, you can save a bundle by not paying the "west of the Mississippi" price.

Venchka
08-04-2003, 10:24 PM
The builder lives in Dulac. He learned from his father. Likes to work with real boards for planking.

Hmmmmm...

Sinker cypress. Varnished. Only thing to use. Now, all you need is a design that can be planked with good sinker cypress.

You really haven't told us what you have in mind as far as the boat's use is concerned or the type of design you are considering.

Amen on the douglas-fir plywood. I found a lovely little spit ketch for sail in Jesuit Bend. It was built out of fir and looked like old crazed porcelin. If you want marine plywood-the good stuff-order from M.L. Condon or Harbor Sales. Figure about $300 frieght for 300-500 pounds of plywood. Actually, if you know anyone in Baton Rouge, you can save a bundle by not paying the "west of the Mississippi" price.

swingking
08-05-2003, 11:55 PM
Sheathed cedar strip or strip planking may be what
you are looking for but it uses all epoxy:

Glenn Ashmore's 45' cutter:
http://www.rutuonline.com/html/the_hull.html

Best of luck
Mat

swingking
08-05-2003, 11:55 PM
Sheathed cedar strip or strip planking may be what
you are looking for but it uses all epoxy:

Glenn Ashmore's 45' cutter:
http://www.rutuonline.com/html/the_hull.html

Best of luck
Mat

swingking
08-05-2003, 11:55 PM
Sheathed cedar strip or strip planking may be what
you are looking for but it uses all epoxy:

Glenn Ashmore's 45' cutter:
http://www.rutuonline.com/html/the_hull.html

Best of luck
Mat

WWheeler
08-06-2003, 04:03 PM
"You should not use any kind of goo in a tube as a substitute for the cotton caulking. The cotton is a structural part of carvel hull construction."

What a lot of rubbish. Typically kneejerk reaction from forum. Lots of wood boats, carvel planked included, have never been caulked with cotton and use polysulphide compounds (aka goo in a tube) to seal seams. I just finished a lapstrake building course where we used such to seal between the laps. However 5200 is an adhesive, you'd want 3m 4200 or Sikaflex.

WWheeler
08-06-2003, 04:03 PM
"You should not use any kind of goo in a tube as a substitute for the cotton caulking. The cotton is a structural part of carvel hull construction."

What a lot of rubbish. Typically kneejerk reaction from forum. Lots of wood boats, carvel planked included, have never been caulked with cotton and use polysulphide compounds (aka goo in a tube) to seal seams. I just finished a lapstrake building course where we used such to seal between the laps. However 5200 is an adhesive, you'd want 3m 4200 or Sikaflex.

WWheeler
08-06-2003, 04:03 PM
"You should not use any kind of goo in a tube as a substitute for the cotton caulking. The cotton is a structural part of carvel hull construction."

What a lot of rubbish. Typically kneejerk reaction from forum. Lots of wood boats, carvel planked included, have never been caulked with cotton and use polysulphide compounds (aka goo in a tube) to seal seams. I just finished a lapstrake building course where we used such to seal between the laps. However 5200 is an adhesive, you'd want 3m 4200 or Sikaflex.

Venchka
08-06-2003, 04:20 PM
Originally posted by WWheeler:
...Lots of wood boats, carvel planked included, have never been caulked with cotton and use polysulphide compounds (aka goo in a tube) to seal seams. I just finished a lapstrake building course where we used such to seal between the laps. However 5200 is an adhesive, you'd want 3m 4200 or Sikaflex.You were reading my mind. :D At least it works on lapstrake, either clinker or dory fasion. Polysulphide being the key. It moves enough to allow for the swelling and shrinking of the planks. You can get a plank off for replacement too.

Sinker cypress. Lapstrake construction. Be still my heart! :D

Venchka
08-06-2003, 04:20 PM
Originally posted by WWheeler:
...Lots of wood boats, carvel planked included, have never been caulked with cotton and use polysulphide compounds (aka goo in a tube) to seal seams. I just finished a lapstrake building course where we used such to seal between the laps. However 5200 is an adhesive, you'd want 3m 4200 or Sikaflex.You were reading my mind. :D At least it works on lapstrake, either clinker or dory fasion. Polysulphide being the key. It moves enough to allow for the swelling and shrinking of the planks. You can get a plank off for replacement too.

Sinker cypress. Lapstrake construction. Be still my heart! :D

Venchka
08-06-2003, 04:20 PM
Originally posted by WWheeler:
...Lots of wood boats, carvel planked included, have never been caulked with cotton and use polysulphide compounds (aka goo in a tube) to seal seams. I just finished a lapstrake building course where we used such to seal between the laps. However 5200 is an adhesive, you'd want 3m 4200 or Sikaflex.You were reading my mind. :D At least it works on lapstrake, either clinker or dory fasion. Polysulphide being the key. It moves enough to allow for the swelling and shrinking of the planks. You can get a plank off for replacement too.

Sinker cypress. Lapstrake construction. Be still my heart! :D

High C
08-06-2003, 05:22 PM
Aiieeee!!!!

High C
08-06-2003, 05:22 PM
Aiieeee!!!!

High C
08-06-2003, 05:22 PM
Aiieeee!!!!

R. Caffery
08-06-2003, 06:42 PM
Gentleman, the idea is an outboard powered skiff, like the 19' vee bottom I've sketched and sent to Dulac. Low power requirements (40 hp, meaning weight is consideration and low deadrise), although I would be satisfied with 20 knots.

The Terrebonne-Lafourche area products are sawn frame, cypress planked work boats that clearly reflect the influence of old-world design. These builders have learned to use plywood but it requires modification to their traditional design. For my needs the plywood version is perfectly adequate, but I'd prefer to have at least some of the attributes of their planked hulls that are almost beyond substitution.

Sadly, here in Louisiana 99 out of 100 custom made boats today are built by welders, and wooden boat craftsmen are a vanishing breed.

Sinker cypress will serve some purposes in my plans but not planking. It's water absorption properties would ruin a trailered boat, I think, and it's outrageously expensive. Most of it is used to make very expensive furniture and cabinetry.

R. Caffery
08-06-2003, 06:42 PM
Gentleman, the idea is an outboard powered skiff, like the 19' vee bottom I've sketched and sent to Dulac. Low power requirements (40 hp, meaning weight is consideration and low deadrise), although I would be satisfied with 20 knots.

The Terrebonne-Lafourche area products are sawn frame, cypress planked work boats that clearly reflect the influence of old-world design. These builders have learned to use plywood but it requires modification to their traditional design. For my needs the plywood version is perfectly adequate, but I'd prefer to have at least some of the attributes of their planked hulls that are almost beyond substitution.

Sadly, here in Louisiana 99 out of 100 custom made boats today are built by welders, and wooden boat craftsmen are a vanishing breed.

Sinker cypress will serve some purposes in my plans but not planking. It's water absorption properties would ruin a trailered boat, I think, and it's outrageously expensive. Most of it is used to make very expensive furniture and cabinetry.

R. Caffery
08-06-2003, 06:42 PM
Gentleman, the idea is an outboard powered skiff, like the 19' vee bottom I've sketched and sent to Dulac. Low power requirements (40 hp, meaning weight is consideration and low deadrise), although I would be satisfied with 20 knots.

The Terrebonne-Lafourche area products are sawn frame, cypress planked work boats that clearly reflect the influence of old-world design. These builders have learned to use plywood but it requires modification to their traditional design. For my needs the plywood version is perfectly adequate, but I'd prefer to have at least some of the attributes of their planked hulls that are almost beyond substitution.

Sadly, here in Louisiana 99 out of 100 custom made boats today are built by welders, and wooden boat craftsmen are a vanishing breed.

Sinker cypress will serve some purposes in my plans but not planking. It's water absorption properties would ruin a trailered boat, I think, and it's outrageously expensive. Most of it is used to make very expensive furniture and cabinetry.

Scott Rosen
08-06-2003, 09:00 PM
Originally posted by WWheeler:
What a lot of rubbish. Typically kneejerk reaction from forum. Lots of wood boats, carvel planked included, have never been caulked with cotton and use polysulphide compounds (aka goo in a tube) to seal seams. I just finished a lapstrake building course where we used such to seal between the laps. However 5200 is an adhesive, you'd want 3m 4200 or Sikaflex.I think you are confused. Lapstrake boats are not caulked with cotton. They are not designed to be caulked with cotton. There would be no place to put the cotton.

A carvel planked boat has caulking bevels that are cut specifically to take the cotton. If a planked boat does not have caulking bevels, then there's usually a different name for it: strip-planked, batten seam, edge-nailed, etc. I'll take your word for it that there have been carvel hulls that were never caulked (not even by the builder), but I've never seen or heard of one.

Now, you could remove the cotton from a carvel hull and squeeze in a bunch of goo. If you're lucky, it'll keep the water out for a while. Eventually, if you actually use the boat regularly, even the best-fit planks will develop edge set, and the goo will let go from the side of one of the planks, and you'll get some leaking that you can't fix without reefing out and replacing large amounts of seam compound. Then the hull will start to work because there's nothing in the seams preventing the planks from moving.

But what do I know? I'm just the garbage man.

Scott Rosen
08-06-2003, 09:00 PM
Originally posted by WWheeler:
What a lot of rubbish. Typically kneejerk reaction from forum. Lots of wood boats, carvel planked included, have never been caulked with cotton and use polysulphide compounds (aka goo in a tube) to seal seams. I just finished a lapstrake building course where we used such to seal between the laps. However 5200 is an adhesive, you'd want 3m 4200 or Sikaflex.I think you are confused. Lapstrake boats are not caulked with cotton. They are not designed to be caulked with cotton. There would be no place to put the cotton.

A carvel planked boat has caulking bevels that are cut specifically to take the cotton. If a planked boat does not have caulking bevels, then there's usually a different name for it: strip-planked, batten seam, edge-nailed, etc. I'll take your word for it that there have been carvel hulls that were never caulked (not even by the builder), but I've never seen or heard of one.

Now, you could remove the cotton from a carvel hull and squeeze in a bunch of goo. If you're lucky, it'll keep the water out for a while. Eventually, if you actually use the boat regularly, even the best-fit planks will develop edge set, and the goo will let go from the side of one of the planks, and you'll get some leaking that you can't fix without reefing out and replacing large amounts of seam compound. Then the hull will start to work because there's nothing in the seams preventing the planks from moving.

But what do I know? I'm just the garbage man.

Scott Rosen
08-06-2003, 09:00 PM
Originally posted by WWheeler:
What a lot of rubbish. Typically kneejerk reaction from forum. Lots of wood boats, carvel planked included, have never been caulked with cotton and use polysulphide compounds (aka goo in a tube) to seal seams. I just finished a lapstrake building course where we used such to seal between the laps. However 5200 is an adhesive, you'd want 3m 4200 or Sikaflex.I think you are confused. Lapstrake boats are not caulked with cotton. They are not designed to be caulked with cotton. There would be no place to put the cotton.

A carvel planked boat has caulking bevels that are cut specifically to take the cotton. If a planked boat does not have caulking bevels, then there's usually a different name for it: strip-planked, batten seam, edge-nailed, etc. I'll take your word for it that there have been carvel hulls that were never caulked (not even by the builder), but I've never seen or heard of one.

Now, you could remove the cotton from a carvel hull and squeeze in a bunch of goo. If you're lucky, it'll keep the water out for a while. Eventually, if you actually use the boat regularly, even the best-fit planks will develop edge set, and the goo will let go from the side of one of the planks, and you'll get some leaking that you can't fix without reefing out and replacing large amounts of seam compound. Then the hull will start to work because there's nothing in the seams preventing the planks from moving.

But what do I know? I'm just the garbage man.

Venchka
08-08-2003, 12:25 PM
Originally posted by R. Caffery:
...Sadly, here in Louisiana 99 out of 100 custom made boats today are built by welders, and wooden boat craftsmen are a vanishing breed.

Sinker cypress will serve some purposes in my plans but not planking. It's water absorption properties would ruin a trailered boat, I think, and it's outrageously expensive. Most of it is used to make very expensive furniture and cabinetry.I agree about the welded construction, hence I went to New Brunswick to have my boat built.

Everyone has a different definition of expensive. I beat the bushes in SE Louisiana and found new cypress for $2.00/BF or less and sinker cypress for $5-$5.50/BF. I would have sent some to New Brunswick if the shipping hadn't doubled the price of the cypress. Alas, too much of the good cypress is ending up in kitchens instead of boats. Get some for your boat before it all ends up in houses!

Are you sure that a trailered boat planked with well sealed and painted cypress will spend enough time in the water to gain significant weight? Might it not spend enough time out of the water to dry out between uses? I wish I knew the answers to those questions myself.

Venchka
08-08-2003, 12:25 PM
Originally posted by R. Caffery:
...Sadly, here in Louisiana 99 out of 100 custom made boats today are built by welders, and wooden boat craftsmen are a vanishing breed.

Sinker cypress will serve some purposes in my plans but not planking. It's water absorption properties would ruin a trailered boat, I think, and it's outrageously expensive. Most of it is used to make very expensive furniture and cabinetry.I agree about the welded construction, hence I went to New Brunswick to have my boat built.

Everyone has a different definition of expensive. I beat the bushes in SE Louisiana and found new cypress for $2.00/BF or less and sinker cypress for $5-$5.50/BF. I would have sent some to New Brunswick if the shipping hadn't doubled the price of the cypress. Alas, too much of the good cypress is ending up in kitchens instead of boats. Get some for your boat before it all ends up in houses!

Are you sure that a trailered boat planked with well sealed and painted cypress will spend enough time in the water to gain significant weight? Might it not spend enough time out of the water to dry out between uses? I wish I knew the answers to those questions myself.

Venchka
08-08-2003, 12:25 PM
Originally posted by R. Caffery:
...Sadly, here in Louisiana 99 out of 100 custom made boats today are built by welders, and wooden boat craftsmen are a vanishing breed.

Sinker cypress will serve some purposes in my plans but not planking. It's water absorption properties would ruin a trailered boat, I think, and it's outrageously expensive. Most of it is used to make very expensive furniture and cabinetry.I agree about the welded construction, hence I went to New Brunswick to have my boat built.

Everyone has a different definition of expensive. I beat the bushes in SE Louisiana and found new cypress for $2.00/BF or less and sinker cypress for $5-$5.50/BF. I would have sent some to New Brunswick if the shipping hadn't doubled the price of the cypress. Alas, too much of the good cypress is ending up in kitchens instead of boats. Get some for your boat before it all ends up in houses!

Are you sure that a trailered boat planked with well sealed and painted cypress will spend enough time in the water to gain significant weight? Might it not spend enough time out of the water to dry out between uses? I wish I knew the answers to those questions myself.