Knocking the knuckles off a Swampscott.

[Reardon]

I'd like opinions on the following design idea.

I know there are several wonderful versions of the Swampscott Dory, and the world may not need another, but a couple of years ago I got the idea of modifying the design for no other reason than to try something new. I'm not trying to improve the design... just trying to have some fun and do something unique.

There are two obvious ways to execute the idea.

#1 What if you ran a batten along the knuckles of each mold, and made the boat round-sided, and then planked it in small strakes, or stripped it. This would increase the volume of the boat.

#2 What if you ran a batten so that the line you drew did not intersect the knuckles, but just touched the inside of the planking wherever a fair line would touch on the inside of each plank? This would decrease the volume.

Any thoughts?

[Daniel Noyes]

Sailing or rowing dory?

It's been done...severaly times, I did it 3 yrs ago and there is a 100+- yr old carvel planked power dory in JohnGardners Building small Craft

but more to your question
the Town Class sailing dory was planked with a smooth sided carvel option in the 30's... it was generally felt in the class that the lapstrake boats were faster wich makes sense to me especially in heavier winds experienced often at Marblehead and Nahant.
The Knuckles and accompaning laps really do have a hydrodynamic effect on the boat especially as speed increases, the laps/knuckles throw spray and break the laminar flow along the hull.

Here is my version of a modern smooth sided sailing dory
Dan
http://farm4.static.flickr.com/3063/3099633754_a1c7063e46_m.jpg (http://www.flickr.com/photos/dansdories/3099633754/in/set-72157608651570153/)http://farm4.static.flickr.com/3269/3098800577_04a05fec7e_m.jpg (http://www.flickr.com/photos/dansdories/3098800577/in/set-72157608651570153/)

[Reardon]

Sailing or rowing dory?

Sorry, I should have been more specific. I was thinking in particular doing this to a row/sail open dory... Probably the Dion Swampscott Dory from The Dory Book.

Gorgeous boat, by the way. Do you have any photos of the interior?

[Roger Long]

What if you ran a batten along the knuckles of each mold, and made the boat round-sided, and then planked it in small strakes, or stripped it. This would increase the volume of the boat.

Sort of like this?

http://www.rogerlongboats.com/images/14DoryLines.jpg

More at:

http://www.rogerlongboats.com/Boats.htm#Dory

As long as you are changing it into something else, you might as well fill out the stern for more sail carrying power.

[James McMullen]

Knuckles are a relic of planking with fewer, wider boards. Make it rounder and strip plank it? If you do it right, you'll end up with a fine boat. . . . .but not nearly as pretty as a lapstrake one, to my mind.
A rounder sided boat lapstrake boat with a smaller flat bottom is just the sort of thing Walt Simmons offers in his Duck Trap Wherry (http://www.duck-trap.com/dtw.html) line--check those out for some inspiration. As far as I'm concerned, there is absolutely nothing prettier than a well lined-off lapstrake boat.

Lapstrake, whether traditional or modern glued lap also involves many tens of hours fewer behind a longboard sander compared to strip planking. I think you'll enjoy the woodworking part of building your boat more if you can avoid all those little bitty strips to mill and glue and sand and sheathe.

[Daniel Noyes]

As long as you are changing it into something else, you might as well fill out the stern for more sail carrying power.

Great minds thinking alike?! :)

She really is a scow type hull rather than a dory...but "Dory Built"
http://sites.google.com/site/dansdories/Slide2small-large.jpg (http://javascript<b></b>:void(0);)
and the interieor shot you asked for Reardon

http://sites.google.com/site/dansdories/Slide10small-large.jpg (http://javascript<b></b>:void(0);)

[Reardon]

As long as you are changing it into something else, you might as well fill out the stern for more sail carrying power.

Unless of course you don't want to negatively affect the rowing performance.

In my humble opinion, when I sail, I don't care how long it takes to get there, but when wind dies out, and I've got to row home, I care about rowing performance.

[Nauvoo]

As long as you're prepared to re-draw and re-fair the entire hull, I guess it could be done. I'm just not sure what you'll gain from all the effort - there are already hulls that possess those features and the lines and offsets are readily available.
IIRC, the Dion dory has wide garboards. Turning those long straight sectional lines into rounded sides will be... interesting.

[Reardon]

As long as you're prepared to re-draw and re-fair the entire hull, I guess it could be done. I'm just not sure what you'll gain from all the effort - there are already hulls that possess those features and the lines and offsets are readily available.
IIRC, the Dion dory has wide garboards. Turning those long straight sectional lines into rounded sides will be... interesting.

I would get the experience of re-drawing, and re-fairing an entire hull an that is kind of what I'm looking for, but I was also looking to have a little bit of a unique outcome, and maybe even a positive one.

[Reardon]

You're trying to reinvent the wheel here. Round-sided Swampscott dories have been around since the 1800s, at least.

The Alden Indian is a six-plank Swampscott with a very narrow bottom. It can be planked lapstrake, or carvel as a truly round-hulled boat.

The difference between a dory with pronounced knuckles and one that appears round-sided is a function of the number of strakes. More strakes result in smaller knuckles and a rounder hull.

Go to the Caledonia Yawl site and look at the difference between the 4-plank and the 7-plank CY.

http://www.mavc2002.com/cyforum/index.php

Yes, I see what you mean, but what I would like to retain is the tombstone transom, and the nearly double-ended water line. All of the rounder sided dories that I've come across seem to lean much further toward sailing than the design I would hope for.

[Paul Pless]

Maybe Norman Bernstein will chime in here; I think this is essentially what he's doing with his Ellipticat project.

[Clinton B Chase]

http://img94.imageshack.us/img94/4269/newdorylines.th.jpg (http://img94.imageshack.us/i/newdorylines.jpg/)

This is the Deblois Street Dory as originally drawn (sorry for bad scan). I drew her round hulled and then lined off for 5-planks. I too wanted to draw my own dory...it is a lot of fun, but I had some training under my belt. I would suggest taking a course with Paul Gartside next summer at WBS and learning how to do it right so that you can build what you drew and get a good boat. If you want to go for it, then go for it. But you have a lot of time ahead of you in designing a boat...be ready for that. If you just want to refair a hull with smooth sides, it is easily done but drawing the body plan with round sides to the inside of the planking and then checking with diagonals to be sure you have a fair hull.

By the way, the D' St. Dory is under construction here in Portland, Maine! I need to snap some photos of the frames being made.

[MTRiverDrifter]

Rarely do I think that dissuading someone from their idea of modifying a boat is proper in this forum (unless, of course the modifications would result in a dangerous or poorly performing boat). However, I can't see why anyone would want to do this one. I'll admit my bias to Swampscotts. They are one of my favorites. Still, there are many lovely round sided boats and many lovely Swampscotts. I can't really see why trying to make one from another is a fruitful activity.

[boylesboats]

I'd like opinions on the following design idea.

I know there are several wonderful versions of the Swampscott Dory, and the world may not need another, but a couple of years ago I got the idea of modifying the design for no other reason than to try something new. I'm not trying to improve the design... just trying to have some fun and do something unique.

There are two obvious ways to execute the idea.

#1 What if you ran a batten along the knuckles of each mold, and made the boat round-sided, and then planked it in small strakes, or stripped it. This would increase the volume of the boat.

#2 What if you ran a batten so that the line you drew did not intersect the knuckles, but just touched the inside of the planking wherever a fair line would touch on the inside of each plank? This would decrease the volume.

Any thoughts?

Just thinking here, you want to round off all the knuckles, strip it like in canoe type stripping.. or carvel planking..

either way, I don't think it'll change much in volume of the boat.. Unless you add few inches to half breadth and depth as well to the length..

[Clinton B Chase]

He'll get a few cubic inches of volume, maybe. And, like the three Chebacco's of three different constructions in new Small Boats, he won't be able to tell the difference in performance between the lapstrake and smooth plank version.

Reardon, I think I understand what your urge is and I am suggesting you design your own boat to "get it out" of you system.

Clint Chase

[Reardon]

Thanks, All for the advice.

I'm convinced that my idea isn't all that unique. While we're on the subject, could anyone recommend any books on small craft design?

[boylesboats]

Thanks, All for the advice.

I'm convinced that my idea isn't all that unique. While we're on the subject, could anyone recommend any books on small craft design?

Did you try John Gardner's "Building Classic Small Craft" (http://www.amazon.com/gp/product/007142797X?ie=UTF8&tag=accessmatters-20&linkCode=as2&camp=1789&creative=390957&creativeASIN=007142797X) ?
Its a start, with 47 boat designs to work from...

[Paul Pless]

Reardon, I think I understand what your urge is and I am suggesting you design your own boat to "get it out" of you system.

Clint ChaseDoes this mean that you're done???

[James McMullen]

I've self-designed several boats. . .had two good ones, had some mediocre ones, and had two out and out, complete and utter failures. Even noted professional designers like Bolger, Atkin, and Garden have had some bummers. The average of all boat designs are mediocre. I'm much less willing to invest my time and energy in building a boat that's not a really, really good one now, so I'm happier letting someone else do the experimenting.

I think you'll have the best success in getting a better than average boat if you are really, really familiar with the kind of boat you really like and are just slightly tweaking a known, successful design slightly towards a different focus than if you try to start too much from scratch. But designing a boat can certainly be just as much part of the entertainment as building or using a boat, so if you are really drawn to the process of having a unique boat despite the potential risks, then I say go for it!