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Part One
The thwarts (the sticks across the boat a little from the ends)
fore and aft (at the front and back) are about eighteen inches
from either end.
The little side panel inwales copied from the Hattory
actually add quite a lot of stability as they are at the lowest
point to stop water coming in when the boat leans to the side
and they add a lot of rigidity. In a pretest float of the Ollie
Punt the boat sagged noticeably in the middle under load without
them and the back rest. These side panels are simply made by laying
a board along the gunwales above where the side panels will go,
mark the line you need to cut with a pencil from underneath and
then cut out with a saw (I used a jig saw ). The backrest is 9
inches back from the center but could be further back if you have
a full body PFD to account for. Because I made mine to join into
both the sides and the side panels at the same time, I made a
couple of dummy cardboard ones before I got it right, starting
with just one end, then tracing that onto a full length bit of
cardboard and then just traced the cardboard onto the final piece
of wood.
Stainless steel metal work screws were used for any permanent
screwing (Keel piece, thwarts, side panels, back rest and ends).
The addition of a skeg (a directional fin) to improve tracking
(staying on line) might be on the agenda as the Ollie Punt is
very good at turning, which makes it a little harder to travel
in a straight line. Perhaps one shaped like the exhaust from a
rocket engine, or a dragon tail with a matching head as a bow
ornament, or a fake outboard motor profile, you could even make
it a boring triangle of wood if you like. All it has to be is
vertical surface area as far from the center as possible, you
can even put them at the front, or a couple of parallel ones right
at the back a little way apart like they have on surf boards.
However, you don't need to travel in a straight line to have fun
on the water. Indeed you don't even need to stay upright, you
just finish up having fun in the water too (temperature permitting).
We painted it white because white Ollie Punts are supposed to
be luckier than gray ones. I was a little frustrated after the
painting because the glue reacted a little with the cheap canned
spray paint I was using and the paint did not dry properly for
about 2 weeks. Thankfully the glue was white too so no-one apart
from me needs to know.
In the first instance pool noodles tucked under the thwarts provided
temporary emergency floatation. You might want to think about
boxing the ends in or gluing split pool noodles to the sides (Wacky
Lassie).
The ukulele headed paddle is a reasonably efficient form of propulsion.
Don't worry I didn't use real ukuleles. I traced the outline of
my ukulele onto some spare plywood I had laying around, enlarging
it slightly by hand. Two 1.5m lengths of 19x45mm pine glued together
and a lot of power planing and rasping and sanding and a few coats
of varnish finished the job. We did try to use a longer paddle
but the additional leverage coupled with the ease of turning made
the boat wander a bit more when trying to travel in a strait line.
A more efficient form of propulsion trialed during the first launch
was derived from a father with flippers on acting as an outboard
motor. Unfortunately photos of this method of propulsion are unavailable
as only my son and I were at the launch and there was nobody else
to hold the camera.
Greater carrying capacity can be generated at the expense of
fore and aft stability by increasing the width in the middle and
decreasing the width at the ends (see below). The complexity of
the curving can be reduced by wasting plywood.
I grant you, like it's predecessors, it looks a little like an
upside down admiral's hat or a pirate hat but it is a lot of fun.
(I think I mentioned earlier it might kind of work as a folding
boat, and with a few tweaks we can get something that might look
more like a pirate ship. I have made a one sheet folding pirate
ship using this sort of design but it is not structurally sound
as a boat. I am working on improvements. Stay tuned for further
developments).
Some more half sheet variations I have not had time or
wife's patience to build
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A shorter fatter dug |
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A squashed octagon |
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A squashed hexagon |
Needless to say these half sheet plans can be stretched across
two or more half sheets laid end on end, or even on any number
of 2/3 or full width sheets. You may even decide to make 2 identical
boats, one with joins in the sides and one without.
I have mucked about looking at how to turn a square half sheet
(4 foot by 4 foot) into a boat but these are in a highly advanced
stage of complete under development.
Other things I learned making this boat (and other times):
A few drywall screws hold things together very well on a temporary
basis and if you use a washer they do not mark the surface too
badly. Staples work too but are not very strong.
A drywall screw leaves a round hole 2 or 3mm in diameter.
As a youngster my father taught me to fill nail or screw holes
(round) with a matchstick (2mm square aspen) and a drop of glue.
A bamboo toothpick is a circle 2mm in diameter and a bamboo BBQ
skewer is a circle 3mm in diameter (though they can come in other
thicknesses). Bamboo is tougher than aspen but aspen will crush
more easily if you are going to put a screw back into the hole
(i. e. when a screw has lost grip due to rot, rust or mechanical
failure).
When clamping things together, a clamping block (scrap wood/mdf/chipboard/plywood)
between the clamps and the objects you are clamping will reduce
the clamps marking the surface of the things being clamped together.
It also helps spread the clamping pressure, especially useful
if you are gluing thin flexible plywood.
A problem that can be encountered with foamy polyurethane glues
or messy workers like me is clamping blocks sticking to the things
you are gluing. To stop this a bond breaking membrane between
the block and the things being glued together is useful. The two
bond breaking membranes I have used are greaseproof paper (AKA
baking paper) and the non sticky side of brown packaging tape.
I have a number of handy blocks pre-covered with brown packaging
tape for just this purpose. As a point of warning, some glues
stick surprisingly well to the sticky side of brown packaging
tape.
There is such a thing as a releasable cable tie. This makes
them easier to reuse and adjust. I am still reusing the ones used
to make the Ollie Punt to keep the cables on my power tools and
USB gadgets tidy. You can release a standard non releasable cable
tie using a pin but it is a bit fiddly.
Five minute epoxy mixed with sawdust makes a great quick set
filler. For the record foamy polyurethane glue mixed with sawdust
makes a lousy filler
Epoxy, polyester resin, foamy polyurethane and soft polyurethane
glues (eg Bostik gold Sikaflex or PL-concrete) are all good at
some things. If you know what you are doing and take into account
their properties when you are joining things they are as interchangeable
as steel and rubber. The hard resin glues with filleting add stiffness,
reducing the need for bracing. Joining the panels using the soft
flexible glues I used is akin to waterproofing the joins without
stiffening them much at all.
Before you make a boat, make a test of designs and techniques
in cardboard first. An old cereal packet and sticky tape are a
lot cheaper than plywood, epoxy and polyurethane.
Before you make a half sheet boat, or any other boat for that
matter there is one step you must take - Learn to swim and use
the right safety gear.
The usual warnings and disclaimers at the end.
You should realize by now that these plans are for extremely
small boats for use in extremely sheltered waters and the only
reason they don't fall into the category "aquatic toy"
is that I do not have a copy of ISO 8124.1:2002 pertaining to
the definition of aquatic toys, which they probably fail. In any
case feel free to write "Not a life saving device" on
them just to be on the safe side. Please follow all local regulations
as for recreational boating. These local regulations usually take
into account local conditions like if you need an arctic survival
suit or a can of octopus repellant and let you know where things
like designated water ski areas are. A water skier would be pulling
bits of plywood out of his or her shins for a week if they hit
one of these designs at speed and while body piercing is fashionable,
having it done to you by a pair of water skis is not likely to
be a good look.
Above all be sensible about the conditions, your abilities and
the abilities of your children. Local authorities really hate
asking questions like "We understand his father put him in
a crocodile infested river in a canoe with 5 inches of free board
- What was his relationship with his father really like?"
or "Why did he attempt his maiden journey across the Atlantic
during iceberg season?". Children should be schooled in water
safety and taught to swim. You are legally responsible for your
own actions and the supervision of children in and around water.
Water is dangerous and cold water more so.
I accept no responsibility for any damages consequential or otherwise
if you attempt to make one of these designs, use these construction
techniques, fall off your chair laughing at one of my stupid jokes,
accidentally poke yourself in the eye with a pencil or attempt
any body piercing techniques mentioned.
No ukuleles were harmed in the making of this article, though
they did get played with quite a lot.
*****
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