Simple flat-bottomed boats built from planks—as planks are still called today in many parts of the country—can be found on almost any of our rivers or lakes. It never occurs to anyone to inquire about the name of the designer who created them: it is clear that this is the fruit of the creativity of many generations of local craftsmen. Over the years, the brevity and expediency of the design have been perfected; The shape of the hull is becoming increasingly better adapted specifically to these conditions. And the natural result: planks built on different pools, even if they have a common characteristic feature - a flat bottom, differ significantly from each other in contours, sizes, and method of construction.
We bring to the attention of our readers a small wooden punt of overseas origin - a skiff boat of North American fishermen. Such boats are widespread in the lower reaches big rivers, flowing into Atlantic Ocean, in vast shallow bays east coast USA and Canada.
Basic data
It is not difficult to note the main features of boats of this type, which determined their wide popularity not only in the past, but also at the beginning of this century, while outboard motors had not yet replaced the oar and sail. Typical Scythian ( English spelling word skiff) is distinguished by a moderate ratio of length to width of the bottom (for example, on our boat it is 3.5:1). This means that the boat is both quite light to move under oars and has good stability, sufficient to be used under sail. The curve of the keel line makes it easier to navigate in shallow water: when the boat runs aground middle part, it is not difficult to turn it around and refloat it. The high freeboard in the bow and the camber of the sides outward along the entire length of the boat indicate that it can be sailed even in rough seas.
We have somewhat modernized the contours of the boat, in particular, we have made the stern wider. Such a widening of the bottom at the transom is necessary for sailing with a motor (its power should not exceed 8 hp) and practically does not interfere with rowing. The fin under the stern, which provides stability on the course even when an inexperienced rower is working, has been preserved.
The skiff has a good carrying capacity. For example, during a short crossing, six or seven people can sit in it.
The body is covered with boards 20 mm thick; Usually one-inch boards are used, planed on both sides. As on a real skiff, it is better to assemble the bottom plating from boards located across the boat. This method has a number of advantages. Firstly, it is easier to find short, good quality boards than long ones. Secondly, short boards are easy to fit tightly one to another. Thirdly, a bottom transverse set is not needed; The rigidity of the bottom flanges and, consequently, the density of the grooves is ensured due to the fact that the span of the board from the cheekbone to the keel is only half a meter (i.e., the same as between the frames for longitudinal plating).
A skiff boat can be built from the most available materials, using a minimal supply of tools and possessing only basic carpentry skills. Need to stock up on inches edged boards 120-150 mm wide from pine or spruce. If the boards are of standard length 6-6.5 m, only 15 of them will be required. The boards should be thoroughly dried and planed along both sides, and those that will be used for the bottom cladding should also be planed along the edges with a jointer so that the gap between the strips is necessarily uniform. Two boards will have to be split into slats for fenders 4, zygomatic stringers 5, underlegs 7 and beads 22.
The transom blank is assembled from two scraps of the widest board. The groove between its upper and lower parts is covered from the inside with a rail 16; it will also serve as a support for the stern can-seat 11. Along the contour marked on the knocked together blank board, the transom is cut to a clean size with a hacksaw. On the side facing the inside of the boat, two strips 15 are nailed along the edges, to which the side plating boards will be attached with screws.
This boat will probably be the first for many novice shipbuilders, so it’s worth taking a closer look at the selection of materials. After all, not just any board is suitable for the hull of a ship that is constantly in the water! Some widespread species (for example, birch, aspen, beech, alder) are generally unsuitable: they absorb moisture and rot easily. For the boat you need to select the most quality wood- without knots, rot, fungal infections, cracks. Rot can be detected by the brown color of the wood in the affected areas; in the sapwood (closest to the bark) part, such areas can be dark blue or a different color. Rotten wood has less hardness than healthy wood.
Parts of boards with large (more than 15 mm), falling out, rotten and loose “tobacco” knots should be disposed of as waste. As a last resort, the knot can be drilled out and a plug of healthy wood glued into the hole; if this board is used for cladding, with inside of the body, a cover is placed on the plug area.
Boards with cracks and cross-layers are completely unsuitable for making set parts. For cladding, it is best to use boards of the so-called radial sawing (at the end of such boards, the annual layers are located across the thickness). Wood in the transverse direction dries out strongly along tree rings, shrinkage along the radius is half as much. Therefore, the gap between the belts of sheathing made from radially sawn boards will subsequently fluctuate less than with tangentially sawn boards (their annual layers at the end cut are almost parallel to the face of the board). Radial sawn boards also warp less when drying.
When preparing boards and slats, you should take into account the finishing allowance: when planing by hand, usually 1.5-2 mm is removed from each face of the board. If the material is raw, you must also provide an allowance for shrinkage - about 1 mm per side.
Too damp boards, as well as overdried ones, are not suitable for building a building. If a chemical pencil leaves a mark on fresh shavings, the board must first be dried. Otherwise, such a board will dry out when the boat is already built and, naturally, a gap will appear. And vice versa, when boards that are too dry and tightly fitted to each other swell in water, the skin will warp greatly and leak; it may even tear off the screws and nails securing the boards to the set.
It is best to use wood with a moisture content of 15-18%, and when adjusting the bottom sheathing, leave a gap of 1.5-2 mm between the edges of the boards, which then needs to be caulked and puttied. Maybe a boat launched will leak at first, but after a couple of days the boards will swell and the leak will stop.
If the material will be dried in a warm room or in summer, in hot weather outside, it is useful to pre-paint the ends of the boards or coat them with resin. This will prevent cracks from appearing and reduce warping of the boards. It is better not to dry the boards in direct sunlight or in close proximity to steam heating radiators.
The stem is cut from timber 75X130X650. First, the longitudinal outlines of the stem are marked on the side edge of the beam and excess wood is removed with an ax and a plane. Then remove the bevels, mark a recess (tongue) under the ends of the sheathing boards and select it using a chisel and chisel. To do this work carefully, you need to take a strip cut from a sheathing board and, applying it to the stem, cut out several nests with a chisel, as shown in the figure. Having made nests of the required depth and slope, cut off the remaining sections to create a continuous tongue.
Now you need to assemble two transverse templates that define correct form the boat hull assembled on the slipway. You can use any boards with a thickness of 12-25 mm, since after assembly these templates will be removed from the body. It is best to draw the outlines of the templates on paper or a sheet of plywood and assemble them by placing the blanks directly on the markings. The lower edges of the Shergen planks 27 must be planed, and the planks themselves must be installed exactly according to the markings - with them the template is placed on the slipway. On the side slats of the templates you need to place the marks LB - the line of the upper edge of the side, and on the bottom slats and shergin strips - the risks DP, i.e. the center plane of the boat. In the corners of the templates (on the cheekbone), make cutouts - grooves for the passage of cheekbone bars 5.
A slipway is a two- or three-inch board, 4.5 m long, placed on edge. Its upper edge must be made straight, aligned with a tightly stretched thread or thin wire. The board is placed on the sawhorse. If the boat is assembled outdoors, drive several stakes into the ground and attach the slipway board to them so that its aligned edge is strictly horizontal. On the upper working edge of the slipway, a DP line is punched with chalked thread.
Assembly of the hull begins with the use of blocks 24 and 25 to attach the transom and stem to the slipway, checking their plumb position. Then both templates are placed on the slipway and fastened with nails through the shergen-bar 27. It is necessary to check that the planes of the templates are vertical - they do not have a slope towards the bow or stern, and that the DP mark on the bottom strip of the template coincides in a plumb line with a straight line on the slipway. Having now pulled the thread over the templates from the center of the stem to the DP marks on the transom, check whether all the DP marks lie on the same straight line.
The templates are rigidly fixed in the adjusted position with slats to the slipway. Then 5 bilge beams are placed in the nests at their corners and secured with 4X50 countersunk screws to the transom and stem and 3.5X50 nails to the templates. The body is now ready for sheathing.
It is recommended to select boards for cladding so that the sapwood part of the board is inside the body. When they swell, the boards will warp, and if they are fastened the other way around, the edges will protrude above the surface of the sheathing, and the fastening screws will receive a greater load.
First, the sides are sheathed. Estimate how many boards will be needed for each side (most likely three). The outer belts are adjusted first. Attach the board of the lower belt to the bilge, grab it temporarily with clamps (you can tighten it with a strong cord or screws) to the bilge beam at the transom and stem. The height of the board must be positioned so that it protrudes above beam 5, and at the ends there remains at least 75 mm of width for fastening with two screws to the transom and stem. The board is applied in the same way upper belt, but here you need to make sure that the middle part of this board is not too narrow. Make sure that you can cover the remaining part of the side with one or, at most, two boards.
On the lower belt, draw a line from the inside of the hull along the lower edge of the zygomatic beam along the lower edge of the side. Transfer the LB marks from the templates, transom and stem to the upper belt. It is also useful to place a vertical line on both boards along the edge of one of the templates - a control line, so that you can then place the board exactly in the place where you tried it on.
Having removed both boards, cut their edges - the edges of the side - according to the markings (on the upper belt you will need to first draw a smooth curve along the LB marks using a long flexible strip). If necessary, you can also cut off the second edge of the top chord if there is too little space left for the middle board.
Having placed and finally secured two processed boards on each side, temporarily lay the middle face boards on top so that they overlap the edges of the upper and lower chords. Pressing tightly middle board, from the inside of the body, outline the edges of the upper and lower chords, then remove the face belt, cut and plan its edges exactly along the pencil lines. This belt should fit between the already installed ones with a gap in both grooves of no more than 1 mm, and the gap should be uniform along the entire length.
Before the final fastening of the boards, the tongue in the stem, the edges of parts 15 and the transom, as well as the edge of the bilge beam adjacent to the skin, must be coated with thickly rubbed paint. The board must be fastened to the zygomatic beam with 3.5X60 nails every 70 mm, bending the protruding end from the inside, as shown in the sketch. It is best to use copper nails, the ends of which can be riveted onto washers. In order not to split the zygomatic beam, the nails are placed in a checkerboard pattern with a distance between rows of 8-10 mm; Holes of a smaller (0.4-0.5 mm) diameter are pre-drilled for them. Hold the hammer by the end of the handle, strike with a movement not of the whole arm, but rather of just the hand. The head of the nail must be well recessed into the wood for subsequent puttying.
When the sides are finally fixed (the boards are temporarily attached to the templates with short nails), the edges of the lower boards protruding above the zygomatic beam are brought flush with it, and a layer of thickly rubbed paint is applied to these horizontal surfaces. It is better to plan the bottom simultaneously from the bow and stern in order to complete the work, as with the plating of the sides, by installing a face board in the middle. Don’t forget to lay the boards with the sapwood side inward and be sure to leave grooves between the edges to allow for swelling of the wood! It is best to attach these short boards to the beams with 4X45 screws (two or three at each end of the board). You should not use boards wider than 160 mm, as wider ones will warp and crack during winter storage.
Drill holes for screws correctly; for the smooth part - with a drill equal to the diameter of the screw, for the threaded part - 1.5 mm smaller. Try to recess the countersunk heads of the screws deeper so that they do not interfere with later cutting through the casing.
As the bottom is covered with boards, saw off their protruding ends along the sides with a hacksaw. This must be done carefully so that the edges of the boards lie in the same plane as the side. Then the sheathing must be planed diagonally with a semi-joint and all the grooves between the boards must be carefully caulked with a thin, even rope of cotton wool.
Prepare an outer false keel 20 and, having previously painted the contacting surfaces, attach it to the sheathing.
Install the triangular stern fin 10 on the screws. It is best to first, when making a false fin, cut a longitudinal groove 25 mm wide at a length of 825 mm into it, into which the fin is tightly inserted. The aft end of the fin must be cut off, as shown in the drawing, and sharpened; otherwise, when sailing under the motor, turbulences and air bubbles will be torn off the fin, due to which the boat will not develop speed due to contact with the propeller.
Now it's time to free the boat from the slipway. Saw through the side slats of the templates and racks 24-25 and turn the body over with the bottom down. Mark the position of the side frames 18, which are made from 25X50 slats directly in place and are attached to the skin with screws screwed from the outside of the hull, two per board. Cut the internal fender beams 4 into the upper ends; to support the seats - the cans - place support beams 7. The ends of the beams 4 at the stem are connected by a breech 3; in the stern, their attachment to the transom is reinforced by horizontal brackets 12 (they are absolutely necessary, just like the vertical bracket 13 in the DP, if the boat will be used with an outboard motor).
Banks 6, 8 and 11 are placed on the supports and secured with screws; the feed can is usually made of two boards in width. Outside, along the entire upper edge of the sheathing, the floor is nailed round section a shoulder bar that protects the edge of the side from damage. Now you can remove the nails that temporarily secured the sides to the templates and remove the templates from the body.
For the boat you will have to make several metal parts: two eyelets (on the stem and on the transom) for tying the boat when parked, clasps and oarlocks, protective strip 2 on the stem. It is advisable to galvanize these parts.
The entire boat must be covered with drying oil and painted after puttying. It is better to paint the surface part in some light color, underwater - make it red, black or green. Ball or brown colors are practical for painting the inside.
It is advisable to make lattice slats for laying on the bottom - there can always be some water in the boat. To support the rower's legs, you need to place a crossbar on the bottom.
The skiff can also be equipped for sailing, but for this, in addition to the mast with a sail, you will have to make a lowering keel - a centerboard and a hinged rudder. The centerboard is inserted - “stuck” - into the well, which is installed in front of the middle bank and connected to it with bars 42. Note Special attention to carefully fit and fasten the well to the bottom using thick paint or waterproof glue. Through the lower bars 47, the base of the well is tightened with the keel and casing using M6X80 through screws with a pitch of 60 mm. The centerboard is cut out of thick plywood, glued together from two or three boards along the width, or made of metal from a sheet 4-6 mm thick. In all cases, the gap in the keel should be 4-6 mm wider than the thickness of the centerboard. The strips 41 in the upper part of the centerboard serve as limiters when lowering it; on a metal centerboard they can be made from squares. The wooden centerboard is kept from floating by a rubber sling 43.
The rudder blade 37 is cut from 8 mm plywood or 12 mm thick boards. The steering wheel is hung using hinges with pins 38; The same loops are made on the transom, but without pins and with mounting strips rotated 180 degrees. To avoid accidentally losing the steering wheel, it must be tied to the transom with a thin cord - sockliner.
The mast is made of a solid round section. It is best to glue it together from two pine bars with a straight, shallow layer. The lower end - the spur of the mast - is made square according to the size of the socket in step 45. The second point of attachment of the mast is the hole in the front bank 6. There is no need to install any guy ropes - shrouds or stays - for a mast that carries a sail with an area of only 6 m2.
The sail is kept the same as that used on real skiffs. It is laced with a 32-piece, the upper and lower corners are tied through holes in the mast. While sailing, the sail is stretched by a 29 rake, the front end of which is tied to the butt 31 on the mast with a reef knot; in the event of a sudden increase in wind, it is enough to pull the end of the line 30 and the sail will be completely de-winded. It is not difficult to pull the mast out of the steppe and put it in the boat. If necessary, the area of the sail can even be reduced by screwing it onto the mast, but then you will have to carry the sail without a rake at all or attach the rake below the tack angle of the sail.
The sail can be sewn from any strong and dense fabric - AM-100, a raincoat, or, in extreme cases, from calico.
In conclusion, we note that a skiff boat can also be built from waterproof plywood. The design of the set, and the method of construction, remain fundamentally the same as for the main version with plank cladding. For the bottom you need plywood 8 mm thick, for the sides - 6 mm.
However, the main dimensions of the vessel do not give a complete idea of the shape of its hull. The exact information about the shape of the body is given by theoretical drawing which is performed, as a rule, in three projections. In order to obtain these projections, the ship's hull is dissected by three mutually perpendicular planes: diametral (DP); main (OP), or water level plane (load waterline); cross-sectional plane, or simply a midsection frame. In accordance with the secant plane on which the image of the vessel is formed, the projection is called side (on the center plane), half-latitude (on the load waterline) or hull (on the midship frame). The reference planes on the basis of which the theoretical drawing of the vessel is obtained are shown in Fig. 2.
However, the projections obtained by cutting the body with only three main planes (Fig. 2) are clearly not enough to depict the shape of the body in detail, so another five to ten planes are drawn parallel to the main planes, the intersection of which with the body gives a number of projections. So, when the hull intersects with planes parallel to the DP, the contours of the vessel are obtained, called buttocks, parallel to the OP - waterlines, parallel - frames. Moreover, each of the projections on two planes has the form of straight lines, and on the third - an actual shape. Such theoretical drawings are necessary in cases where the housings have rounded shapes. For, in which both the bottom and sides are formed by the skin, the theoretical drawing is reduced to the projection of the lines of the keel, chine, upper edge of the side and outlines of the frames (Fig. 3).
The methods for constructing a theoretical drawing are common to any vessel, including a punt, so every shipbuilder should know the principles of its construction.
The choice of basic dimensions, as well as the shape of the body, is the main and most difficult question when designing a ship. Solving this issue requires knowledge of the basics of ship theory (there is such a science) and the widespread use of statistical material. The simplest and surest way to make your work easier is to use ready-made drawings of a suitable boat. You can analyze the characteristics of a number of boats as analogues and try to create your own design based on them. In any case, it is very useful to build a 1:10 or 1:5 scale model of the boat. In the process of creating such a model, the homemade shipbuilder will delve into the construction technology, see future boat not only in the plane of the drawing, but also in space, will receive additional incentive to build a boat and confidence in the success of the enterprise.
Table 1 shows the characteristics of common rowing boats.
| Table 1. Rowing boats | ||||||
|---|---|---|---|---|---|---|
| Character ristika |
Boat type | |||||
| "Bull-2" | "Berezka" | "Okhtinka" | "Fofan-F2" | "Nerd" | "Wave" | |
| Body contours* | ABOUT | ABOUT | ABOUT | ABOUT | |_| | o_o |
| Length, m | 3,58 | 3,98 | 3,94 | 4,6 | 4 | 2,8 |
| Width, m | 1,48 | 1,14 | 1,17 | 1,22 | 1,27 | 1,04 |
| Side height, m | 0,50 | 0,47 | 0,39 | 0,47 | 0,38 | 0,28 |
| Weight, kg | 105 | 80 | 87 | 100 | 90 | 17 |
| Capacity, persons | 3 | 3 | 2 | 3 | 3 | 2 |
| Housing material | Glass- plastic |
Birch veneer on glue | Boards | Boards | Boards and plywood | Prore- zine fabric |
| Oars, pairs | 1 | 1 | 1 | 2 | 1 | 1 |
| Set- tion (payols, scoops) |
+ | + | + | + | + | + |
| * According to the contours of the hull, ships are divided into rounded ( symbol ABOUT); U-shaped (U); V-shaped (V); flat-bottomed (|_|); sea sleigh (W); longitudinally and transversely stepped, or stepped (G); inflatable (o_o). | ||||||
From Table 1 it can be seen that the boats, despite the large difference in length, have almost the same width, which is caused by the need to install oarlocks at the optimal distance for rowing. The fact is that working with oars, for example. When the rowlocks are located at a closer distance to each other, as in inflatable boat"Wave" becomes less effective. The length of the two-seater boat “Okhtinka” is almost equal to the length of the three-seater boats “Bychok-2”, “Beryozka” and “Botnik”. Thus, we can conclude that there is simply nothing more convenient than a small, lightweight, simple punt boat with a hull sheathed from boards. I came to this conclusion several years ago when I was trying to solve a similar problem. Then I came across a description of the “Dragonfly” motor boat, which differed from other boats in that its bow was somewhat “cut off”, as a result of which it became shorter by about one spacing (the distance between the frames), the chine approached the upper stern of the side at a considerable distance from center plane, the slight deadrise of the bow end of the hull turned into an almost flat bottom in the midship frame area. As stated in the description, the “Dragonfly” motor boat is designed for sailing on rivers and small lakes with an outboard motor of 10...12 hp. With. I built such a boat entirely from sheets of D16 aluminum alloy 2 mm thick, and I also made the Z-shaped frames from these sheets. All connections are riveted. The seams were sealed with thickly ground white lead. The boat turned out wonderful. The two of us are on it with a 20 hp Whirlwind outboard motor. With. developed a speed of about 45...50 km/h. The boat moved quite well under oars, was maneuverable and had good stability. Its characteristics: length – 3550 mm; width – 1400 mm; side height – 450 mm; weight – 75...80 kg. In general, it turned out to be a good universal boat for two for sailing under oars or with an outboard motor. The theoretical drawing of the Dragonfly boat is shown in Fig. 3, and the values of the plaza ordinates are in Table 2. Let us recall that the plaza is the place where a theoretical life-size drawing of the ship is drawn, after which templates are made from the drawn parts, according to which the ship parts are made.
| Table 2. Plaza ordinates of the motor boat “Dragonfly” | |||||
|---|---|---|---|---|---|
| Frame No. | Height from Op, mm | Half-latitude from DP, mm | |||
| Keel | Cheekbone | Board | Cheekbone | Board | |
| 1 | 320 | 340 | 370 | 330 | 350 |
| 2 | 90 | 200 | 415 | 460 | 560 |
| 3 | 30 | 110 | 445 | 540 | 660 |
| 4 | 10 | 60 | 455 | 600 | 690 |
| 5 | 0 | 35 | 455 | 640 | 695 |
| 6 | 0 | 25 | 440 | 670 | 670 |
| 7 | 0 | 25 | 420 | 670 | 610 |
| 8 | 0 | 25 | 405 | 670 | 560 |
Please note that Table 2 does not show the plaza ordinates of the deck of the Dragonfly motor boat, which covered the first three spaces. The theoretical drawing shows the deck. It can be seen that it has an inclination towards the bow of the boat hull. The fact is that while moving, the bow of a motor boat rises somewhat and takes a horizontal position when the boat is planing.
Knowing the performance of the “Dragonfly” motor boat, taking into account the simplicity of its design and the manufacturability of its construction from sheet material, a rowing boat with a wooden frame and plywood hull sheathing with Lgab equal to 3050 mm was built in its likeness. The theoretical drawing of the “Dragonfly” was slightly changed (Fig. 4). The plasma ordinates are summarized in Table 3.
| Table 3. Plaza ordinates of a two-seater rowing boat | |||||
|---|---|---|---|---|---|
| Frame No. | Height from Op, mm | Half-latitude from DP, mm | |||
| Keel | Cheekbone | Board | Cheekbone | Board | |
| 1 | 400 | 430 | 450 | 330 | 350 |
| 2 | 140 | 270 | 450 | 440 | 500 |
| 3 | 50 | 150 | 450 | 530 | 610 |
| 4 | 0 | 30 | 450 | 600 | 700 |
| 5 | 0 | 30 | 450 | 600 | 700 |
| 6 | 0 | 30 | 450 | 580 | 680 |
| 7 | 10 | 40 | 450 | 530 | 630 |
| 8 | 70 | 100 | 450 | 470 | 570 |
As is known, according to the mode of movement, boats are divided into four types: floating, moving in transitional mode, planing and moving on hydrofoils. Since our rowboat was supposed to float and not plan, we raised the bottom at the stern a little. Otherwise (with a flat bottom of the stern and a wide transom), when the boat moves behind its stern, a passing flow of water would form, capable of providing significant resistance to the movement of the boat. For the same purpose, as well as to improve the maneuverability of the boat, the camber of the sides at the stern is similar to the camber on the fourth frame of the Dragonfly hull. We shortened the boat by 50 cm, and the side height became the same along the entire length of the boat. The steepness of the bow of the keel - the stem, as well as the deadrise of the bottom in the bow of the boat were increased. In terms of its dimensions, our boat became similar to the inflatable double boat “Volna”.
Here are the characteristics of our boat: length – 3050 mm; width – 1400 mm; side height – 450 mm; weight – 60...70 kg.
Our boat moved well under the oars. It turned out to be quite spacious and very convenient for fishing. It was not forbidden to install on it outboard motor power 5...8 l. pp., for example, “Surf” or “Veterok-8”.
For a solo DIYer who prefers to relax on the water without companions, we recommend shortening the boat by one spacing, that is, by 50 cm. Then the length of the boat will be 2550 mm, and the result will be a good single-seater boat.
For both a two-seater boat and a single-seater, a slight decrease in half-latitude is permissible, for example, by 100 mm. As a result, the width of the boats will be 1200 mm, which is comparable to the width of the boats “Berezka”, “Okhtinka”, “Fofan-F2” and “Botnik” (see table 1).
So, we have decided on the outline of the boat's hull. Now you can start
Punt, as they say in " Explanatory dictionary living Great Russian language" by Vladimir Dahl, this is a vessel that sits, by its other dimensions, shallowly, and therefore unstable, capsizing. Well, more about operational properties We’ll talk specifically about punts a little later, but now let’s remember those floating structures that people once used and continue to use now to overcome various water obstacles and use rivers, lakes and seas for fishing, hunting and for transporting various cargoes. The first ships were probably rafts made of tree trunks fastened together. Boats made from whole trunks hollowed out (burnt out) from the inside were known already in the Stone Age. The island peoples of Oceania, combining two such one-day boats into one design, invented a catamaran with excellent seaworthiness and the ability to sail at high speed. Some peoples of Siberia still have traditions of building boats from tree bark (“vetka”, “birch bark”, “omorochka”). For such boats (“pie”), the North American Indians made a narrow, long frame of wood, which was covered with tree bark, and sometimes with skins. Separate pieces of bark (skins) of the shell were sewn together with tree roots or leather twines. The seams were coated with resin to ensure the tightness of the joints. The peoples living along the shores of the northern seas (Eskimos, Chukchi, Aleuts) built boats using a similar technology, but with a closed top so that they could not be overwhelmed by waves. So the oarsman-hunter, wearing a special apron, in such a boat feels like part of the boat. A similar, completely closed top leather small boat, which among the Eskimos, Chukchi and Koryaks is called a kayak, allows hunters of sea animals to boldly go far into the open sea. Even if the boat capsized, an experienced rower could return the kayak to its normal position with one deft movement of a two-bladed oar.
When people mastered the production of bronze and iron products, boats began to be “sewn” from boards, connecting the latter with nails, staples, and bolts. Large oars and sailing ships, intended for transportation along rivers and seas of significant cargo and large quantity of people. Thus, at the end of the first millennium, Russian boats up to 20 m long and up to 3 m wide took on board 40...60 people along with military equipment and supplies. Nowadays, ships are made of plastic, steel, aluminum and even high-strength cement (for example, yachts made of reinforced concrete are known).
With development modern species water transport Traditional rowing, sailing and motor boats have not lost their importance. Where there are bodies of water, these boats continue to faithfully serve people. By the way, although the term boat has been included in the names of some classes of warships (gunboat, submarine), usually the word boat only means a small vessel without a deck. Moreover, even a small motor boat with a buried top is usually called a cutter.
Now let's get back to our punt boat, which is one of the simplest both in its form and in boat manufacturing technology. The punt refers to vessels for individual use (amateurs). The flat bottom of the boat allows it to be used in shallow waters (upper reaches of rivers, small rivers, ponds, canals), where there is no noticeable excitement. However, do not assume that a punt must have a completely flat bottom. Typically, such boats are characterized by a slight deadrise on the bottom, which allows them to overcome small waves much better, that is, to navigate “softer” waves. The wide spread of boats of this type is facilitated, firstly, by the above-mentioned relative simplicity of design, as well as the possibility of construction using non-scarce materials. sheet materials, for example, boards, plywood, aluminum alloy sheets and, secondly, a huge number of small reservoirs and rivers that are accessible only to punts and rubber boats.
As already mentioned, a boat is a vessel without a deck, superstructure, or deckhouse. Strictly speaking, a boat is a small vessel made from one hull. In turn, the hull consists of a frame (a set of the ship’s hull) and a casing attached to the frame - a shell that provides the hull with water resistance. The contours of the boat's hull, as a rule, are quite smooth; sharp points are characteristic only of its bow and stern (in punts, only the bow is usually sharp). The front end of the boat is called the bow, and the rear end is called the stern; the side walls of the hull - the right and left sides (when viewed from the stern).
As you know, the technical and operational characteristics of any vessel, and our punt is also a vessel, depend on its main dimensions (length, width, side height, etc.), displacement, capacity and similar indicators. When building a boat, we will mainly need its dimensions, so we will look in detail at the main dimensions of the vessel (Fig. 1).
So, the main dimensions of the vessel include:
L – design length, that is, the distance between the perpendiculars restored to the longitudinal from the ship at the level of the load waterline at the points of intersection with the leading edge of the bow and the trailing edge of the stern;
Lnb – the greatest length of the body without protruding parts;
Lgab – overall length, that is, the length of the body, taking into account the parts protruding beyond the casing;
B – design width of the hull, measured in the middle of the hull length at the level of the load waterline between the outer edges of the frames ( transverse parts the frame of the ship's hull, reinforcing the side plating);
Vnb – the greatest width of the ship’s hull without protruding parts;
Vgab - overall width, that is, the greatest width of the vessel, taking into account the parts protruding beyond the hull (fender, shoulder);
H – design height of the side, equal to the vertical distance between the inner surface of the horizontal keel (or the main line OL) and the upper edge of the side in the plane of the midship frame. (Please note that in shipbuilding, the word midship, meaning middle, does not always coincide with the middle of the ship, but indicates the widest part of the ship. Note also that the main line OL is parallel to the longitudinal axis of the ship and passes through the place of contact between the inner surface of the hull and the lower central part midship frame).
Ngab – overall height side, equal to the calculated height of the side taking into account the protruding parts located on the bottom.
T – design draft, corresponds to the distance from the load waterline to the top of the horizontal keel.
Тgab – overall draft, which is equal to the calculated draft taking into account the protruding parts located on the bottom plating, for example, the keel. (A little more about the main dimensions of the vessel can be found at).
The ratio of the main dimensions largely depends on seaworthiness of the vessel (boat). Thus, the length-to-width ratio (L/B) affects propulsion and controllability (the larger this quotient, the better the vessel’s heading stability, but the worse its agility). The ratio of the length of the vessel to the height of its side (L/H) characterizes the strength of the hull (the lower this value, that is, the greater the height of the side for a given length, the stiffer and stronger the hull). However, it must be remembered that the height of the side of the boat is dictated by navigation safety requirements. For example, the cargo capacity of the vessel and its controllability depend on the ratio of the height of the side to the draft (H/D). At the same time, with increasing H/T value, cargo capacity increases, and controllability deteriorates due to an increase in freeboard windage.
However, the main dimensions of the vessel do not give a complete idea of the shape of its hull. The exact information about the shape of the body is given by theoretical drawing. But more about that on