The Sharpie project

Construction

Text and pictures: Olle Jeppsson

Sharpie 600

Illustration: Björn Thomasson


Contents:

Sharpie 600

 

 

 

 

 

 

Materials

The choice of material to the boat, I have done according to the principle: No more expensive or better than necessary. The idea behind the construction is that it will be a good boat at a reasonable cost, but for the sake of compromising security. My advice to those who wants to build, is to choose the best that you can afford, but not higher quality than necessary.

Since all surfaces are coated with fiberglass/epoxy or epoxy alone, so no need to spend a small fortune on marine plywood. Everything is still well preserved. The point of this construction technique is that this boat is, like a plastic boat, "maintenance free", but with wooden feel and charm!

My choice:

Backbones, frames/bulkheads, centerboard and rudder:
12mm pine / fir plywood, ordinary build quality. Make sure it has as many veneers as possible
Stringers: Larch. It is also possible with the northern spruce or pine.
Planking: 10mm pine plywood. Good quality
Deck and other curved surfaces: 3x4mm plywood which is laminated on the spot to get the right shape.
Details that require strength/durability: Oak (other hardwood will do of course)
Spars, mast, boom and gaff: Northern fir (dense light and strong)
Veneered surfaces in the cockpit and interior: Honduras Mahogany.
Deck surface: Teak 6x45mm.
Decoration strips: Ash (contrast to the mahogany surfaces)
Edge strips in cockpit and interior: Teak
Tiller and bowsprit: Ash (contrast to the mahogany surfaces)
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The hull

Construction start: September 1999

Alla spant på plats

The backbone of the hull is constructed of two longitudinal and several transverse (rib) plywood sections. These are bound together by slits to form a stable unit, which simultaneously serves as a building jig. It's all here assembled upon some pallets to reach a comfortable arbetshöjd.

When you build up these sections so you can see that everything is level. Of course, you have transferred the design waterline from the drawing for each section.

In the picture you can see that centerboard drum is positioned slightly offset to starboard. In place is also stringers, i.e. the bar that represents the transition between the bottom and hull side.

Däcks- och slagvägare på plats It has also deck stringers installed, thus the bar at the transition between the hull side and deck.
Bordläggning av 10mm plywood
The planking consists of 10 mm plywood. Unlike the frames (12mm) I chose here a somewhat higher quality of pine plywood to withstand any run aground better.
Bottenskivorna The bottom consists of 2x12mm plywood. Laid with overlapping seams. Glued and screwed.
Glasfiberduk och epoxi

Time for a fiberglass cloth and epoxi. The hull sides get a stock sheet (165g / m²), while the bottom gets two. It gives better protection when you go into shallow water or when transporting the trailer. Epoxy imposed under the supplier's instructions.

Once the plastic has hardened and surface polished, it is time to paint the surface. I used a 2-component polyurethane varnish (International). It provides an unmatched durability.

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Cabin & deck

Skrovet vänt Now the hull, which until now has been built upside down, waiting on an even keel. Time to continue with the cabin and deck.
Sharpie 600 20x30mm strips (kravel and stringers), mounted along the cabin side and aft.
Sharpie 600 Fitting 12mm plywood for the deck.
Sharpie 600 The cabin roof's camber makes it impossible to produce from a single sheet. Therefore, it is laminated by three pieces of 4mm. The bottom is stiched in the stringer and is then glued (1-comp. Polyurethane). Then the next layer is fastened with pins at the edges and pushed down with a staple gun. After hardening, this is repeated with sheet no. 3. When this has dried, loosened the whole package, and the pins from the layer one are cut and filed down. Now you can laminate and paint inside.
Sharpie 600 Well, now it has happened a little more. Cabin sides, roof and cockpit are in place. Even the hull has got a little more paint.
Sharpie 600

The deck can be surfaced in various ways. Most importantly, it must be non-slip. I have chosen to add a teak deck, providing an in my opinion, good looks and gives a natural non-slip surface. Although it costs time and money, I thought it was worth the both.

A painted deck can certainly be just as good. It is entirely a matter of taste, like so much else on board.

Sharpie 600

Here I have mounted moldings (oak) along the cabin roof and mounted the not quite finished cabin door.

(Apparently, I also got a bit more natural color in the picture, because I photographed without flash and compensated for fluorescent light.)

Sharpie 600

An overview picture showing how the boat looks like now (02-12-01), with the cabin door, mast tabernacle and bowsprit in place.

Sharpie 600

 

The cabin doors, made from 10mm plywood that I veneered with mahogany. In the framework of oak, I routed a 5mm deep fitting for the ply.

Sharpie 600

Here I route some decoration in the frame to get more life into the surface.

Ruffdörrarna på plats

Testing of the finished pieces. Some work with the frame and mounting the hinges remain. A pair of grid ventilators will also be installed.

Sharpie 600

Here are the doors on hinges. Bottom of picture shows the grid of Here are the doors on hinges. In the bottom of the picture shows the grid on the drain.

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Cockpit

Sharpie 600

The cockpit structure makes it plenty of spacious compartments. Here I'm working with templates of masonit, for the cocpit seats. They must follow the hull shape properly.

The picture shows a very good tool, a Japanese Dozuki-saw. A very thin and fine-toothed thing that you pull towards you when cutting. It gives a perfect result in surprisingly large dimensions. Available at Clas Ohlson.

Sharpie 600

An engine can be good even in a small sailboat. There are different options for installation: Inboard, outboard on the transom or outboard motor in a motor well. I chose the latter. An inboard engine costs a lot and become a permanent installation.

An outboard on the stern disturbs the boat's lines (my opinion). But mounted in an engine well, you get a good compromise. I have chosen a 6hk 4-stroke short shaft outboarder.

Sharpie 600

The cockpit is coming to shape.

De veneered surfaces (Honduras mahogany) have been provided with a contrasting decorative strip of ash. Similarly, the tiller is ash.

In ancient times used the box to make spears because of its strength and toughness.

Sharpie 600

A simple back support of 12x40mm Teak is both stylish and comfortable. The length of the cockpit makes makes it useable for sleeping overnight. With a simple boom tent you get shelter.

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Interior

Pentryt

There is also room for a small galley on board. Of course not full headroom. On the picture the cabin top has not been placed yet, and you see the little sink and hand pump for fresh water.

Under a flip-up hatch will be the containers for fresh and waste water.

VA-systemet

Here is "VA" system up close. Two 25-liter plastic containers serve purpose as fresh water respectively waste water tank. Not very advanced but simple and functional.

On the left is centerboard drum and turning block for the operation of the centerboard. Rope runs backwards, through the bulkhead to the cockpit.

Sharpie 600

Interior of the "salon". Despite the limited dimensions, there are a lot of storage space and seating for four adults. There is plenty of space for two full-length beds, too.

Interiör

View from the "lounge" and aftwards. To the left is the galley and to the right room for a small navigation area.

Here you can even imagine placing a small chem toilet (Porta-Potti or similar).

   
   
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Rig

Bild av Sharpie 600 med gaffelrigg. Illustartion: Björn Thomasson

Björn Thomasson has designed two alternative rigs. Yawlrigg with lug mainsail and ditto mizzen, as well as here, sloop rig with the gaff sail.
A Sharpie 600 with lug rig, you can see here: Björn's website (http://www.thomassondesign.com/katalog/mina-batar/sharpie-600).

My choice fell on the gaff rig, because of the more classic look, and that it in this case probably is better suited to offshore sailing.

The mast is mounted on the deck in a so-called mast tabernacle. That means more space below deck, and that the mast can be folded.

Sharpie 600

The mast is made hollow, with internal reinforcements at the ends and where the gaff rests. I also took the opportunity to put a plastic tube into the mast to mount a top lanterna.

It is important to have as little weight as possible up in the rig, so the gaff boom was also made hollow. However, it is advantageous to allow the boom to be massive.

Gaffel, bom och mast

Here you see the finished rundhulten.

From left: Gaff, boom and mast. Making the mast and gaff hollow saves about 30% by weight.

   
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Centerboard & rudder

Centerbord

The centerboard is made of 3x12mm plywood. I have chosen to also strengthen the front and bottom with oak. In the front lower part, I have added about 25 kg of lead. This provides a low center of gravity.

An alternative to plywood is to make the centerboard of a 10mm steel plate.

Rodermall

The rudder is in two parts, an upper and a lower which makes it retractable.

The picture shows the masonite template.

The boat's modest depth, approximately 200mm, with the retractable rudder and centreboard, makes the boat almost able to sail right up on the beach.

   
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Other

Sharpie 600

A cheaper alternative to brass valves are, as here, making them of wood (teak). A routing template and a router is needed.

Sharpie 600

...and this was the result.

Sharpie 600

A sliding hatch must be added. Here is the frame and rails. A brass bar makes it all run smoothly.

Sharpie 600

The hatch is made of 2x4mm plywood, which are laminated in the same way as the cabin roof.

Sharpie 600

The hatch in place. It has got a layer of mahogany veneer and lined with strips of oak.

I have painted the cabin roof white with "International Interdeck", which provides a non-slip surface.

Vakuumlimning

Veneering requires proper pressure all over the surface, when you glue. A lot of scrap and a flat surface works pretty well, but a more sophisticated way is with a vacuum. I have used both methods. The picture shows the latter.

The surfaces coated with glue and veneer is applied. Then packed it into a bag of plastic sheeting as carefully taped together. Some kind of vacuum pump, in my case, an electric, connected by tubes also packed into the plastic. The result is very good.

Of course, the result in this case depends on the starting material.

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Tools

Here I intend to show you what tools I have access to. Some are more necessary than others. Machinery makes things much easier, but you can do well with good hand tools.

In the case of cutting tools, one should invest in good quality, which holds the edge. There's nothing worse than dull chisels and knives. On the machinery side, we consider how much you will use them. A good drill for example, is perhaps useful in other contexts as well.

Sharpie 600

Machines

Top: A circular saw mounted in a simple saw table.

Row 2: Electric hand planers (Bosch) with the addition of the planning and jointing. A good combination. A disc sander.

Bottom: Drill (cordless). Jigsaw.

Sharpie 600

Hand tools

Safety Equipment: Ear protection, goggles, face mask (with spare filters).
Planes.
Drills, countersinks, plug cutters.
Hacksaw, handsaw, dozuki saw (great tool).
Abrasive pads, hard and soft. Hammers, screwdrivers, wire cutters.
Calipers, tape measure, steel rulers.
Square, bevel, compasses.
Mallet, chisel, knife, crafts files.

Sharpie 600

A good tool is a vertical drill. In my case, an inexpensive countertop model with decent accuracy.

Sharpie 600

If you have the chance, a good grinding machine a good investment. The Tormek has a wide selection of jigs and it gives a perfect result.

Sharp chisels, planer blades and knives are extremely important.

Sharpie 600

A "must"

You can almost never get too many clamps. A number (10?) clamps of various sizes and preferably some fast clamps (perfect if you work alone), you must have.

Similarly glue clamps, at least 15-20 pieces, of different sizes.

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© Olle Jeppsson, 2002