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Chuck
We've had the almost 16ft Julie skiff and the 12ft Ella skiff
- here comes the 14ft Sunny skiff.
For your info, sometime I'd like find the time and energy to
cook up sailing versions (and a sailing/camping in the case of
the Julie), and plans for a more traditional build for each. I
also think there should be a 17ft model for two rowers.
People are looking at these plans in numbers though I'm only
aware of one Julie skiff being built so far.
Gav
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Sunny skiff
14ft length overall by 4ft beam, by 465lbs displacement,
designed for stitch and glue construction using 1/4in or 3/8in
4ft by 8ft plywood
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Sunny Skiff |
This boat has been designed by an amateur with no qualifications
in boat design or boatbuilding and should be regarded as experimental.
The designer accepts no liability for any loss or accident that
may result from following these instructions or their attendant
plans or from any loss or accident that may follow from using
this boat.
- Design points
The Sunny skiff as laid out in these plans is a lightweight
general purpose stitch and glue flattie skiff for use in sheltered
waters with no strong currents or tides. It is also meant to be
a simple and quick stitch and glue building job of a size that
is convenient for building in domestic garages made to take a
small to medium-sized car, which probably describes the building
area available to most people.
The boat is designed with rowing primarily in mind, though it
could also be used with a VERY small outboard of no more than
2hp. Too many accidents take place because outboards of the wrong
size have been used, and far too many of these are fatal.
The name came from my mother, who sadly passed away some time
ago. She is pictured holding a boat model in the pages of Ultrasimple
Boatbuilding.
Compared with the Julie
skiff, the form of a boat like this must be
influenced by the need to work in a decent amount of displacement
into a shorter hull, as anyone who compares the lines drawings
of the two boats will quickly see. The Sunny skiff is therefore
a more curvy boat than her big sister, but less so than her little
sister, the Ella
skiff.
The stem is angled somewhat in order to turn splashes and ripples
downward, for I know that dryness is an important part of comfort
in small craft, especially for those unused to boating.
Sailing enthusiasts will note that I have not drawn any details
for a sailing version of this boat and I would prefer that no
builder should add a sailing rig to this bare design. I feel that
open boats like this with no built-in buoyancy should not be converted
for sailing without serious thought about the safety and construction
issues.
- Construction issues
Readers may with to read my book Ultrasimple
Boatbuilding published by International Marine
and available from high street and online bookstores, especially
Duckworks.
Before going any further, it's important to check the size of
the plywood available to you, as it comes in different sizes in
different countries around the world. A sheet of ply in the UK
and the USA is likely to be 4ft (1220mm) wide, and 8ft (2440mm)
or a little more in length, and this is the size these plans are
made for. However, in the rest of the world including Australia,
New Zealand and continental Europe ply sizes can vary considerably.
I'd like also to emphasise the importance of model-making. The
download package for this boat includes drawings intended to be
used to make a model, and I'd ask you to please make a model first
as it will show how the boat will look but perhaps more importantly
how each component part goes together and contributes it's pennyworth
towards creating a usable boat with a rigid structure.
The system of coordinates I use to define the shapes of the panels
on the 4 by 8ft plywood panels is the aspect of the plans most
likely to cause concern in the minds of boatbuilders. This is
because the approach seems unfamiliar, but in fact the technique
is straightforward – and is the same as the one most of
us used to draw graphs when we were at school - though I'd argue
that building a boat is a darn sight more fun than maths lessons.
Each pair of coordinates describes a particular point on a plywood
sheet. The first number (the X-coordinate) in each pair of coordinates
is a measurement along the bottom of the sheet, while the second
in the pair (the Y coordinate) is a measurement up from the bottom
- that is along a line that is a right angle (or 90 degrees) from
our point along the bottom.
Before plotting each of these coordinates one by one, I find
it best to square off the material into twelve-inch squares, as
it's so much easier to plot from your squaring off than it is
to mark out each measurement from the panel edge, but also because
it helps to show whether you material is really 8ft long.
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Layout of panels |
Ply is frequently a little longer than it's supposed to be, and
if you don't remove the extra before starting to build the boat,
you could be in trouble, with some components longer than others.
For squaring off ply, I often like to use a drywall square, but
a tape measure and the side and edge of another sheet of plywood
will do the job perfectly well, if slightly less conveniently.
Once the lines have been drawn, you need to draw your cutting
lines. I do this by first finding a flexible batten to help re-create
create the curves, and I've found that perhaps the best thing
to use is an 8ft plastic moulding of the kind one can buy in any
do-it-yourself story.
To make the curves, drive small nails into the material at each
of the plotted points, lay the batten along the nails, using weights
to hold it up to the nails. When the batten is in place and reasonably
secure, draw along the length of the cutting line using a soft
carpenter's pencil. After a few hours of plotting and drawing,
you should be able to see that the lines on your ply correspond
to those on my plans.
A final word of warning on marking out. There are a lot of coordinates
to plot here, and that means there are a lot of opportunities
to make mistakes, both for the builder and for the designer. If
when you have plotted the points and drawn the lines there are
any that don't look right, check them, and check them again. Remember
the old carpenter's advice that one should measure two or three
times before cutting once. If after all this checking you're in
doubt that I may have made an error please contact me at gmatkin@clara.net
- I don't want you to risk wasting material unnecessarily because
of a mistake I have made.
The next job is to cut the material out, and to build the boat
using the stitch and glue boatbuilding method, otherwise known
as tack and tape construction.
Anyone who has used this method before will see immediately how
it will work with this design, but if any of you reading this
haven't worked this way before I won't explain it here but I would
recommend reading it up at almost any epoxy supplier's website.
One example is the UK Epoxy website: http://www.epoxy-resins.co.uk/.
I'd make only five general construction points.
First, these drawings have been created with the intention that
the fore and aft sections of the bottom and sides should be joined
by epoxy tape on either side of the join, rather than using butt
blocks or a scarf. I often prefer this method for several reasons:
it's easy and unlike using butt blocks, I don't afterwards have
to cut the thickness of the butt block from any frames they happen
to coincide with. If you do build this boat using butt blocks,
you'll no doubt have to cut some material from the central frames
to make up.
Second, I have drawn no plywood reinforcement for the bows of
this lightweight boat. This is because builders working in stitch
and glue are expected and advised to reinforce the inside of the
bows with several thick layers of epoxy and tape. I'd suggest
applying a single layer of tape, then two further layers laid
each to either side, and finally a fourth and perhaps a fifth
layer of tape over the joint on the centreline. Each layer of
tape should be extended onto the bottom of the boat to make a
smooth and strong joint, with each layer of tape extends little
further aft. It's worth also lapping two lengths of tape on the
sharp edge of the bows one sits to one side of the bows and the
other to the opposite side with the long edge covered by two layers
of cloth.
Of course, if you'd rather make a false stem to fit on the inside
of the bows, that's fine with the designer, but please don't forget
to include a knee against both the bottom and foredeck.
Third, there are two ways of treating the frames in a boat like
this: stitching and glueing frames on both sides; or adding cleats
around each frame, and trimming to fit the shape of the inside
of the boat. It's up to you, but I'd be tempted to go all-s&g
except for the supports under the thwarts and sternsheets.
Fourth, once the sides are bent around the frames, you'll find
that the sides become slightly curved where they meet the frames,
and that there will be a small gap between the frame and the side-plank.
That's only to be expected from the geometry of the side planks.
All you have to do is to make sure this gap gets well filled with
epoxy and covered over with tape in the usual way. The joint will
be as strong or stronger than a similar joint with no small gap.
Fifth, it's clearly impossible to make stitch and glue fillets
inside a closed box. Instead, the seats must be supported by cleats
– pieces of wood of say 1 by 1? running across the frames
from one side of the boat to the other. Standard epoxy fillets
should be used where the seats meet the sides of the hull.
There are a several special construction features of this boat
that require a little explanation.
Gunwales I'm very much in favour of gapped inwales
- they make a boat very rigid, and they look good. However, in
a rowing boat built to this design for many people they're no
doubt a complication too far and heavier gunwales will be preferable.
If you go for the heavy gunwale option, I'd suggest laminating
two lengths of 1 by 1 1/2in material to make a gunwale that's
close to two inches wide. You'll find that the frames I've drawn
will leave a hard corner that you will want to round off. If you
go for the gapped inwales, you'll need to work out your gaps so
that they coincide with the ply frames. Here's a tip: don't try
to work your gaps around the oarlocks – just make that area
solid, wherever the oarlocks fall.
Doubled stern Sterns have to be strong and I'd
prefer to double this part of the boat, particularly if there
is any chance that it might be used with even a small outboard.
Positioning of oarlocks I haven't drawn a position
for the oarlocks as this can be a matter of taste. The standard
view is that they should be about 12in aft of the aft edge of
the transom, but some argue this distance should be the length
of the rower's forearm, and this may be particularly important
for taller rowers. Oarlocks should be mounted on solid blocks
of 8-12in in length, 5in in depth and 2in thick or so. They will
have to be shaped to match the curve of the boat, and if you are
using gapped inwales they should be cut so that they fit into
the inwale and can be glued to it (with the gapped inwale installed
first, naturally).
Oar length There are a lot of views about oar
length. Some say the length of an oar should be of half the beam
(from lock to lock) times three, plus 6 inches (6ft 6in), others
that the length of an oar from lock to grip should be half the
beam times three plus 2 inches (6ft 2in), still others use much
more complicated calculations based on the speed of the boat and
how lightly it rows. However, I'd say about 7ft will be perfectly
acceptable where this boat is concerned.
Thwart If there is anywhere on this boat where
a piece of good quality timber with nicely chamfered or rounded
edges, this may be it. Think of the hours you're looking forward
to spending on it! Also, be aware that the thwart is 8.25in wide
with the panel for the seat meant to sit on top of the frames
– use this to define the position of the second frame that
supports it.
Seats and decks The foredeck is in two parts,
and the seam between them will benefit by being backed by scrap
ply 6in wide. It will also benefit from being reinforced with
cleats, as will the seat aft.
Foot brace If the boat is to be used as a tender,
a foot brace might get in the way, but if it is to be used for
pleasure rowing, then I'd suggest knocking up a a comb.
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