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 The intheboatshed.net Sunny skiff

Design by Gavin Atkin - London, England   

Free Plans!
Click HERE to download

 

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

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.

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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