This is a boat optimised highly towards single person rowing at the expense of
other capabilities.
At time of writing, October 2009 I have 3.5 sheets of high quality marine
plywood in the backyard. Additionally I have 2 sets of oars from my larger dory,
one set of which I could use for this boat.
This is a design I am contemplating for November of this year, 2009. This is in a response to rowing my 18ft dory. I have found that too large for single person rowing in a strong breeze due to high windage. Thus in response since I am considering a smaller rowing boat, designed only for one person. The design is low in freeboard and is not optimised for sailing.
The idea is for a rowboat that is to be used only in moderate conditions. It can survive more robust conditions if that eventuates. It is similar in
appearance to some smaller banks dory, such as the South Haven light banks dory. However this boat is
designed for greater speed at the expense of rough water capability. To optimise the design for speed as opposed to rough water
capabilities, the stem and stern are much more vertical
Main features of this boat when compared to my previous 18ft dory are
Greatly reduced windage
reduced weight
Easily car-toppable
Easy to build
Requires a small amount of materials
Has greater initial stability for those less agile and for children
Is optimised for one person, with ability to carry 2 at times
Long waterline length for good speed
Optimised for smooth water, with ability to survive moderate conditions if encountered
Some more features of this boat are
Rowlocks are on outriggers to increase rowlock-rowlock separation
A 4x2 timber is used to support the rowlocks
Buoyancy compartments are fore and aft
The thwart can be moved into one of two positions, for single and 2 person rowing
The bottom panel is 66xm max width, which is 6cm wider than my present dory
Midsection freeboard is 26cm at 140kg
The top of the stem is 40cm above the waterline
The rowlocks pivot out a few degrees to give the ideal angle. The axis of rotation is not vertical
A skeg will need to be added, this is not shown in diagrams
Rowboats are meant to have a narrow stern, this has a reasonably narrow stern
Because this is a one person recreational rowboat, and not a workboat, measures can be taken to optimise it for that use. This is done by enclosing off large bow and stern sections. If this was done in a work boat there would be no space to put fishing equipment. However this is not an issue in a small recreational rowboat. The use of a near vertical stem and stern results in a long waterline length that results in greater speed. The freeboard is low to reduce windage and allow for
progress and control in a moderate wind.
This design has a great deal of similarity to Michael Storer's 15ft rowboat,
Flint 14 by Ross Littingstone and the Whisp Rowboat by Steve Redmond.
It should be noted that this is not a balanced design. It is optimised for low cost
construction, it is not designed with sailing in mind, and nor is it really
optimised to carry other passengers, though this can be done, . If passengers are carried aft, then some
water containers forward of the rowing position would be prudent for trim. The
thwart can be moved forward a little to assist in trim. From experience I feel that a built in water ballast tank is the best way to go as opposed to removable water
containers, maybe closer to the stem?.
Final Comment
Am I reinventing the wheel? Has this all been done previously. Does Gavin Atkin have something out there like this? I do not want to go to 15ft because I want to keep it small and easier to cartop. This design is created to have almost identical waterline length to my 18ft dory (due to large overhangs). this is where the 13ft length comes from
NEWS - October 2009 I have changed the lines slightly in last couple of days. The new lines are
at top, the earlier set are at bottom of page. The changes are more flare at the
bow as per the boats of Atkins and co, more stern freeboard for better balance.
I also levelled out the boat, this makes no difference in building but means
that the diagrams make more sense.
Since I now am thinking of 55cm travel between 2 rowlock positions, I think I
need two sets of outriggers, not the one as shown.
I have put the design file online for anyone to download it. You need to
install the free hullform software from hullform.com to view the shape. The file
can be downloaded from here
Here is an alternate thwart arrangement. Perhaps it is simpler lighter and more flexible than the first attempt.
And now (april 2010) after about 8 months of reflection I have come back to these lines and feel they could be refined a fraction more. After looking at some skiffs in Peter Culler's book and also looking at some skiffs as drawn by John Gardener, I can see that the forefoot should be a fraction deeper. Additionally
midsection freeboard has been increased to 25cm at 200kg. This is a modest freeboard, higher than before but certainly not overly high. The adjusted lines are shown below
My feeling is that this should be a very nicely balanced design. Easy to row, but with more initial stability than my banks dory. It has moderate windage and yet retains reasonable freeboard. The boat has sufficient length to carry three people, yet is not so long as to be difficult of store and manhandle. The waterline length is quite reasonable so as to give OK performance under oars. The stern is wide enough to support the weight of an outboard aft and yet still narrow enough so as not to drag the stern whilst rowing. The design is easy to build, whilst retaining high flare which will enable the craft to survive reasonably rough conditions (though not extreme conditions).