Re: double rowing dories

Hi Bruce,

> The thing about measuring "big" using LOA is that with double ended
> boats, most of the "pointy ends" doesn't really count towards
> capacity. "Bigness" measures better if you compare the displacement
> value.

True. The Long Light Dory has a few feet of overhanging bow and transom that reduce the waterline length. But it's oh so beautiful!

I suspect that the original Light Dory is a bit too big to cartop anyway (although I'm sure it's been done), and if you have to use a trailer, might as well build the longer boat. I know I love mine.

Jon

--- Inbolger@yahoogroups.com, BruceHallman <hallman@...> wrote:

>
> ...I recall PCB writing that there are two limiting factors,
>
> 1) length (which associates with the drag that a hull makes when it
> approaches hull speed, long boats have higher hull speeds).
>
> ...at odds with...
>
> 2) wetted drag (which associates with wetted surface area, long
> boats have more wetted drag)

PCB also wrote of,

3) Reynolds number - with longer waterline higher Reynolds numbers and more resistance. The trade-offs between available human power, speed, wavemaking and wetted area drag, and those of available human power, length, R No, speed and wetted area. (see A Cruising Canoe, SBJ, also in the cartoons group IIRC)

> So, if the boat isn't going to be strenuously rowed at near hull
> speed, shorter can at times be better.

Yep, similar conclusion. A different conclusion for strenuous atheletics where shorter times can be better.

Spur II would have to be the "one". Protected water, open water, any water.

Do we wish to row fast, as an athelete? Do we wish to row slow? Do we wish to cross an ocean? Do we wish to accomplish a specific task, as for a particular way of fishing some stretch of water for example? Do we wish to be extravagant? Do we wish to be understated? Do we wish to camp? Do we wish to take advantage of limited time? Do we wish to row in company? Do we wish to row as a company? Do we wish for solitude? Do we wish we could have it all, not too big, not too small, just right, enough utility, the most of rowing? Then Spur II is the Goldilocks choice.

The Thomaston Galley rowing performance on protected waters pleased Bolger very much, and he kept one himself for quite a time. Good into the wind too, if not into a chop...

I believe he thought Crystal in standard lifeboat-dinghy form too heavy, and spoke of that after having owned one for some time. He suggested it might be a beaut one if built minimally, stripped back to bare essentials for rowing, and drew one that way. This last suggestion in fact seems well supported by the performance of one built foam-sandwich. This boat went very well according to the builder-owner, Gary Lepak, whose reports will be found here in the archive along with a photo (yes, sadly, only the one pic).

--- Inbolger@yahoogroups.com, "Peter" <pvanderwaart@...> wrote:
>
> I'd be interested in opinions about what Bolger plywood non-dory design is the best for rowing. Crystal, perhaps?
>

My June Bug rows well (better than I do) and does well with one rower and one or two passengers.  With one passenger, the rower uses the front seat and oarlocks.  With zero or two passengers, the rower uses the middle seat and oarlocks.

On Tue, Aug 30, 2011 at 1:01 PM, Peter <pvanderwaart@...> wrote:

> If you want more speed from two rowers, you are going to need more length.

Often true. Still, I recall PCB writing that there are two limiting factors,

1) length (which associates with the drag that a hull makes when it
approaches hull speed, long boats have higher hull speeds).

...at odds with...

2) wetted drag (which associates with wetted surface area, long boats
have more wetted drag)

So, if the boat isn't going to be strenuously rowed at near hull
speed, shorter can at times be better.

> I'd be interested in opinions about what Bolger plywood non-dory design is the best for rowing. Crystal, perhaps?

Of course, there are different types of rowing. My personal favorite
in "my fleet" is the Cartoon 5 double ender, seen in BWAOM as
"ultralight rowboat for home builders".

> The thing about measuring "big" using LOA is that with double ended
> boats, most of the "pointy ends" doesn't really count towards
> capacity. "Bigness" measures better if you compare the displacement
> value.

I agree with this. Dorys are "short for their length" so to speak, since the long ends are not in the water. If a short length is important to you, then you can do better with a transom boat.

I'm not a rower, but there are a couple of other notions that I can throw out there. (You probably already know most of it.)

Since one rower is only a small amount of power, you do best when you fit the whole package of rower(s), oars, and boat together with care. As ever with boats, there is a tradeoff between speed and weight. If you want more speed from two rowers, you are going to need more length.

On the other hand, PCB wrote about the advantages of a crew of two, one rowing, one as passenger, trading places as desired. With that style, you would need a more burdensome boat rather than a longer boat.

I'd be interested in opinions about what Bolger plywood non-dory design is the best for rowing. Crystal, perhaps?

On Tue, Aug 30, 2011 at 9:14 AM, D`Arcy <drittich@...> wrote:

>
>
>
> The Big Dory seems, well, a little big. I was hoping to keep to 15' or 16' LOA..maybe that is not practical for a double rower? Although, the 15' Gunning Dory looks like it handles two rowers pretty well...
>

The thing about measuring "big" using LOA is that with double ended
boats, most of the "pointy ends" doesn't really count towards
capacity. "Bigness" measures better if you compare the displacement
value.

The stretched long dory 536 has a reasonable max displacement of 720
lbs and the Gloucester Gull of 460 lbs (my estimates).

Balance is the issue. If two rowing stations was important then I would live with the longer length. Check out his building site for the long Dory

http://www.kolbsadventures.com/long_dory_1.htm

HJ

On 8/30/2011 8:14 AM, D`Arcy wrote:

The Big Dory seems, well, a little big. I was hoping to keep to 15' or 16' LOA..maybe that is not practical for a double rower? Although, the 15'Gunning Dorylooks like it handles two rowers pretty well...

On Tue, Aug 30, 2011 at 12:07 PM, John and Kathy Trussell<jtrussell2@...>wrote:

 

WoodenBoat publishes an Annual magazine called “Small Boats” and the 06/07 issue has a write up on the Light Dory. The owner (who is also the associate editor of “WoodenBoat) says:

 

There is absolutely no doubt that this boat is at its best for solo rowing. With two people at the oars, it trims down by the head and you can’t steer. With a third person […or equivalent weight…] aft, things balance out all right. But such a load makes freeboard too low for really pleasant rowing, and you wouldn’t want to venture out in too much chop in that condition. … Somebody who likes this design but favors tandem rowing or a lot of company would do well to look at the 19’ version that Bolger worked up to answer this very issue, with four rowing positions to choose from so you can get the trim just right.

 

 

I have no personal experience with either the Light Dory or the Big Dory. The only thing I would wonder about on the Big Dory is suitability for solo rowing. Perhaps someone has built one and can comment.

 

JohnT

 

 

 

---

From:bolger@yahoogroups.com[mailto:bolger@yahoogroups.com]On Behalf OfBill Howard
Sent:Tuesday, August 30, 2011 11:34 AM
To:bolger@yahoogroups.com
Subject:Re: [bolger] double rowing dories

 

 

PCB designed a stretched dory for Dynamite Payson.  Three movable seats, 19'6" long.  Four sets of oarlocks shown in Dynamite's book,Instant Boatbuilding with Dynamite Payson.  

 

Plans are available for $40 from Harold H. Payson & Co, Pleasant  Beach Road, South Thomaston Maine 04858.

 

 Building instructions in Dynamite's book are sparse -- slightly less than two pages.  Dynamite wrote, "It's not my intention here to give you a blow-by-blow instruction for building her fight through to the end, but I will help you get started and offer help with some of the harder parts."

 

 

On Aug 30, 2011, at 11:10 AM, D`Arcy wrote:

 

I have been planning to build a Gloucester Light dory for some time, but I am becoming more and more interested in double rowing dories, and am not sure the GLD is that suitable for this without modifications that are probably beyond me. If it is modified for two, can one still row it? Are we talking about three sets of oarlocks and three seats at this point? Or, should I be looking to other designs if I really want a double rower?

 

D'Arcy

 

 

Gunning Dory looks like a good choice.  

The Big Dory seems, well, a little big. I was hoping to keep to 15' or 16' LOA..maybe that is not practical for a double rower? Although, the 15'Gunning Dorylooks like it handles two rowers pretty well...

On Tue, Aug 30, 2011 at 12:07 PM, John and Kathy Trussell<jtrussell2@...>wrote:

WoodenBoat publishes an Annual magazine called “Small Boats” and the 06/07 issue has a write up on the Light Dory. The owner (who is also the associate editor of “WoodenBoat) says:

There is absolutely no doubt that this boat is at its best for solo rowing. With two people at the oars, it trims down by the head and you can’t steer. With a third person […or equivalent weight…] aft, things balance out all right. But such a load makes freeboard too low for really pleasant rowing, and you wouldn’t want to venture out in too much chop in that condition. … Somebody who likes this design but favors tandem rowing or a lot of company would do well to look at the 19’ version that Bolger worked up to answer this very issue, with four rowing positions to choose from so you can get the trim just right.

I have no personal experience with either the Light Dory or the Big Dory. The only thing I would wonder about on the Big Dory is suitability for solo rowing. Perhaps someone has built one and can comment.

JohnT

---

From:bolger@yahoogroups.com[mailto:bolger@yahoogroups.com]On Behalf OfBill Howard
Sent:Tuesday, August 30, 2011 11:34 AM
To:bolger@yahoogroups.com
Subject:Re: [bolger] double rowing dories

PCB designed a stretched dory for Dynamite Payson.  Three movable seats, 19'6" long.  Four sets of oarlocks shown in Dynamite's book,Instant Boatbuilding with Dynamite Payson.

Plans are available for $40 from Harold H. Payson & Co,Pleasant  Beach Road, SouthThomastonMaine04858.

Building instructions in Dynamite's book are sparse -- slightly less than two pages.  Dynamite wrote, "It's not my intention here to give you a blow-by-blow instruction for building her fight through to the end, but I will help you get started and offer help with some of the harder parts."

On Aug 30, 2011, at 11:10 AM, D`Arcy wrote:

I have been planning to build a Gloucester Light dory for some time, but I am becoming more and more interested in double rowing dories, and am not sure the GLD is that suitable for this without modifications that are probably beyond me. If it is modified for two, can one still row it? Are we talking about three sets of oarlocks and three seats at this point? Or, should I be looking to other designs if I really want a double rower?

D'Arcy

I agree.  The Gouchester Dory is a single person boat.  The stretched "Long Light Dory" design 536 is the way to go if you want two or three people...

PCB designed a stretched dory for Dynamite Payson.  Three movable seats, 19'6" long.  Four sets of oarlocks shown in Dynamite's book,Instant Boatbuilding with Dynamite Payson.  

I have been planning to build a Gloucester Light dory for some time, but I am becoming more and more interested in double rowing dories, and am not sure the GLD is that suitable for this without modifications that are probably beyond me. If it is modified for two, can one still row it? Are we talking about three sets of oarlocks and three seats at this point? Or, should I be looking to other designs if I really want a double rower?