contents:
Breasy - sailing skiff
Sea Tiger - junk rig sail
Dutch Treat - a model with leeboards
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___"Breasy"_____________________

Many a small skiff designed for rowing, would also carry a simple rig for use when the conditions were right. Especially those on and off shore breezes that come when the warm air over land rises and the cool air over the water slides in to take its place, and vise versa.

The sprit is a simple, easy rig, you will find it common in a lot of home made sailboat designs. The sail can be designed in all sorts of shapes, with the spar extending the sail higher than the mast head, lower, some almost square.

It also has a simple safety feature.
-The sprit can be easily ‘scandalized’, that’s when a line that holds the spar up is quickly undone, bringing the bulk of the sail with it, all with a quick tug. A trick that comes in handy when a strong gust of wind suddenly appears.

This model introduces a different method of rigging your model with a sprit sail.
Rather than tying a line around the mast, and then have that line tie to the spar, this rig has a line that runs right through the plastic straw that holds the sail to the mast. Inside the straw that forms the sleeve, you tie a stopper knot (I used a figure of eight).

The hole that you poke through the sleeve is off to one side of the mast, for the line that ties to the foot of the spar has to be long enough to stretch around the mast when the sail is on the opposite tack, a length of about a half inch does the job. If you find tying knots difficult when you don’t have much in the way of length to work with, a small plastic cleat can be used at the foot of the spar. With the line squeezed through a cleat, you can adjust its length with a tug.

The advantage of this rigging method is that the line that leads to the heel of the spar does not have to work its way around that extra sail area that sticks out from the sleeve.

The 1/4in. straw that is used as a sleeve was covered with brown packaging tape giving the mast a wooden look, and also reinforces the plastic straw. (The trick to doing this is to stretch out the tape, carefully roll the straw onto the tape until it is all covered. Cut off the extra tape at the ends, then slice the straw along its length, peel away any overlapping tape. Don’t forget to snip off the corners at the top and bottom ends of the slice.)

The hole that you poke through should come from inside the sleeve, and be just large enough for the line to slip through, other wise the stopper knot will pop through. Design the sail with paper first and make sure you poke the hole in the sleeve where you want it, since you cant adjust its position. Note: when you do reduce sail (furling against mast) the peak of the sail slides down the spar.

The sail was made with vinyl sheet, although a little more heavy than poly-bag plastic, the model sailed fine, even with such a high aspect ratio.

For a while, I had been working on several more complicated model sailboat designs mostly on MkII and MkIII’s.

I had almost forgotten how much fun the ‘little guys’ (MkI) can be to sail. I made this one on a double ender, with a white hull and a clear finish on the deck. The centerboard, a little shorter than the finished one supplied, was painted flat black. The high aspect ratio sail, (almost rectangular) provided plenty of power, and combined with the double ended hull made the model swift and manoeuvrable.

rating: Stability...........Good
Windward Ability.......Good
Manoeuvrability........Very Good
Swiftness..............Good
Sail adjustability.....Good
Ease of Construction...easy   :^)

__Sea Tiger______________________

The junk rig has been used for centuries and is unique to the orient. Similar to the lug sail, it is suspended from a spar that sets part of the sail in front of the mast. Bamboo skewers are used to construct the rig for this model boat. A package of 100 cost about a dollar.

Bamboo is considered by some to be the "lumber" of the future, although bamboo is not a tree but a member of the grass family. Bamboo is strong, yet light weight due to its hollow core. It has a straight grain, is flexible, and can be steam bent. It grows quickly and is pervasive in its growth. It is also a hardy plant that is even being grown commercially in Canada and other (unexpected) places around the world.

The junk rig is one of the early sail designs with good windward abilities. The junk rig probably developed out of the sprit rig. The junk can be said to be the first sail to use full battens, centuries before the concept was used in the west that have full battens, made with lightweight flexible materials.

The bamboo poles used in junk rigs connect the horizontal panels of the sail giving it strength as well as flatness, giving the sail its windward abilities.

Sea Tiger was my first attempt at making a junk rig, as this was made on a MkI hull, I kept it simple, and only used five battens.

The sail is attached to the top spar with some tape at the forward end, and with a small rubber fitting on the aft.

  Or you can use more tape, either way, the line that you use as a halyard that is tied to the spar should be adjustable fore and aft.

The sail is attached to the boom with rubber at both ends, this allows the sail to be adjusted fore-and-aft and accommodates the rigging lines.
For the best windward abilities, the sail should be rigged with the leading edge close to the mast as shown. You can adjust the sail more foreward if you will be doing a lot of downwind sailing.

The battens in between are attached using strips of clear tape, (the type with the matte finish, looks better than glossy.)

Place a small strip of tape at the end of the batten, then a strip on the edge of the sail with some of its length sticking out as shown in the drawing, this end gets folded over and sticks onto the sticky side of the tape placed on the end of the batten.

Again, note that both sticky surfaces join together. The batten should be slightly shorter than the width of the sail, to allow a slight draft to form. Aways, use a brand name tape, and press the tape firmly onto the surface of the sail.

The hull was given a scow entrance and a skeg at the run. (see illus.) and then painted a rich 'Chinese Red'. As this was made on a Mk I model, I did'nt bother attaching the sails battens along the mast, this can be done with rigging lines called sheetlets, I will save that for a three masted junk (in the works) on a Mk II.

Sea Tiger proved to be a swift and very manoeuvrable model. It is definitely an attention grabber.

Performance Rating

Stability...........Good
Windward Ability.......Very Good
Manoeuvrability........Very Good
Swiftness..............Good
Sail adjustability.....Fair
Ease of Construction...Acceptable

__Dutch Treat_______________

  In Europe, the sport of racing boats is said to have begun in the Netherlands, where annual canal boat races were held. The faster boats were able to demand higher cargo rates, and win contracts to deliver goods where speed was important. The word 'yacht' is derived from the Dutch word 'jaght' that was the name given to these events. The Dutch word 'jaght' meaning 'to hunt, or chase.'

Going to see "the jaght" became a popular event, and over time, canal barges were replaced with boats that were built for the wealthy, specifically designed to go fast. The name of the event eventually became the name of this type of boat, boats designed for speed and luxury.

The spirit of competition, and the prestige of winning 'the jaght,' both for the boat owners and the builders, led to the many innovations (and much of the language) that make sailing what it is today.

One innovation was the use of lee boards. Lee boards are similar to centerboards, but the lee board is mounted on each side of the hull. These could be pivoted down into the water to provide a shallow draft boat with lateral resistance, without relying on a deep keel.

The lee board could be raised up out of the water to allow boats to pass through shoals, and increase the boats' speed when going downwind, when there is no need for lateral resistance.

The model 'Dutch Treat'- is inspired by the typical Dutch sloop, 'sloop' is another Dutch word meaning 'swift.' It has lee boards mounted on each side of the hull.

To build a model like this you need to buy two small, solid brass wood screws, at least three times as long as the lee board is thick.
A #4 x 3/4" round head screw is what to look for.

Also get a piece of 1/4" wood lath. The size of the lee boards is shown in the drawing, compared to the stock keel board.

It is a good idea to make a pattern of your lee board out of cardboard first, to get the right location of the pilot holes. The holes should be placed so that when the boards are raised they clear the waterline.

Just like all centerboards, the lee boards are shaped to act as foils, the leading edge is rounded, with the thickest part just forward of the middle, and the rest gradually tapering down to a thin flat edge at the back.

The lee boards are tightened with a small screwdriver tight enough that the boards stay in position. The lee boards should also be supported slightly away from the sides of the hull, to keep them vertical. (see illustration) This can be done with a small piece of plastic aquarium tubing or a bead with a hole large enough to fit the screw through. If you use the plastic tubing, cut one end on a slight angle to make it fit against the flair angle of the hull.

The modifications to the stock hull of 'Dutch Treat' are extensive, so if your woodworking skills are up to the challenge, here goes. The bottom of the stern sweeps upward to the waterline, this is described as the hulls 'run.' There is a ridge along the hulls centerline that is left untouched, that forms a skeg.  (see illustration)

To form this, first mark the hull with a pencil to define the area of wood you want to remove.
- Using a fine toothed back saw, cut two parallel slices into the hull on each side of the centerline. Be careful not to cut beyond your working lines.
- Then, securing the hull in a wood vise, cut into the hull on both sides until you have reached the first cut. You then sand, and sand...

The bow area's flare angle was increased by about 10 deg. starting at the waterline at the stem, and the amount trimmed off tapers down to nothing at about 1/4 of the hulls length. (See the shaded area in the illustration) You can use a block plane or a wood rasp.

As always, mark working lines on the hull first. Finish off with sandpaper and smooth down the edges.

The mast is placed in the second mast step and the mainsails' foot, (bottom) rises slightly, so that it can swing clear of the lee boards when the boards are raised.

The jib is tied to the head stay down at the tack, then the line leads up to the sails head and ties again, then up to the mast, this simplifies the whole process, but you must take care to tie that second knot in a way to keep the sail taut without stretching, the sail too much.

A short length of bamboo skewer was taped to the foot of the sail, this is another shortcut. Note: Sometimes it pays to put a little more time into making your model, a ‘shortcut’ may save time at first only to cost you more time later.

A line was tied onto the main sheet to branch out forming a "Y". The line was tied onto the jibs clew, the mainsheet is adjusted as it is pegged down into the mast step so that the jib and main work in tandem.

There is no centerboard to attach ballast to, but the lee boards give it a good deal of stability. When the lee boards are raised the boat will sail in very shallow water, having less than an inch draft.

The rudder was attached to the deck at the stern, and it was made to sit shallow in the water. It is a great boat for exploring tidal pools.

Rating...
Stability...Very Good (no ballast)
Sail adjustability...Good
Swiftness...Good
Manoeuvres...Fair
Course stability...Good

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"A good time to keep your mouth shut is when you're in deep water. " - Sidney Goff