Fig. 29
Let us turn our attention to model war-ships. A torpedo-boat destroyer is clearly illustrated inFigs. 28and29. This is very simple to construct and makes a pleasing craft when finished. The hull is formed by two blocks. One of these forms the raised deck on the bow of the boat. The cabin is built up on this raised deck. It will be seen that the part of the hull that rests in the water is formed by one block. In building boats of this nature the constructor should be careful to keep them long and slender, since torpedo-boat destroyers are always of this type. They are high-speed craft, and their displacement must therefore be as small as possible. Some of these boats carry fourstacks and some two. The author prefers four stacks as giving the boat a better appearance than two. The two little cabins near the stern of the boat are placed there merely to take away the plainness of construction. The guns mounted forward and aft are merely round pieces of wood with a piece of wire bent around them and forced into a hole in the deck.
Fig. 30
The boat-builder should not be satisfied with one or two of these craft; he should make a whole fleet. This will afford theaverage boy a great amount of pleasure, since he can add to his fleet from time to time and have official launchings. Each boat can also be given a name and a number. A little gray paint on the hull of these boats and black on the stacks gives them a very presentable appearance.
Fig. 31
A battleship is shown inFig. 30. A battleship should be at least twice as long as a torpedo-boat destroyer. A view of the battleship as it will look in the water is shown inFig. 31. By carefully examining this drawing the builder will be able to see justthe number and shape of the blocks that enter into the construction of the craft. The battleship is provided with four main batteries mounted in turrets, one forward and three aft. A mast is also built, and strings run from it to the top of the main cabin and to the end of one of the turrets mounted aft. A screw is placed through the centers of the fore and aft turrets, so they can be turned to any position. Battleships should be painted gray. It will be necessary to place rather a heavy keel on the boat just described in order to bring it down to the proper depth in the water. Otherwise it will be topheavy and will capsize very easily. A fleet of battleships and battle-cruisers can easily be made according to the foregoing instructions, and the builder should not be satisfied with producing only one.
A pleasure yacht is illustrated inFig. 32. The hull of this craft is formed by two boards nailed together. The cabins are very simple, being formed by a solid block of wood with a piece of cigar-box wood tacked to the top. The windows and doors are marked in place with a soft lead-pencil, andthe stack is mounted midway between the two cabins. A wireless antenna should be placed on the boat, with a few guy-wires from the masts run to various parts of the deck. A lead-in wire also runs down into one of the cabins. The hull of this boat should be painted pure white. The deck can be left its natural color, while the stack should be painted black and the cabins white with green trimmings.
Almost any type of boat can be produced by the use of simple blocks of wood and other miscellaneous pieces easily brought to shape from ordinary materials. This method of construction offers a wonderful opportunity for the boy to exercise his creative faculties.
BOATS are propelled by two different systems. Some inland-water boats still employ side paddle-wheels, while ocean-going vessels use the more modern propeller or screw.
The paddle-wheel really acts as a continuous oar. Such a wheel is shown inFig. 33. As the wheel goes around the paddle dips into the water and pushes the boat forward. If the direction of the boat is to be reversed, the rotation of the paddle-wheels is reversed.
Fig. 33
Before passing onto the screw, it may be well to explain just how a paddle-wheel causes a boat to move. When a man gets into a rowboat, he generally pushes himself off by placing his oar against the dock or shore and pushing on it. That is just what the paddle does in the water. It dips intothe water and pushes against it. It must be remembered, however, that water is unlike a solid substance and it "gives." When a man places his oar against the bank and pushes it, the bank does not move, and all of the man's energy is used in starting theboat. Water, however, does not remain stationary when the paddles push against it, and therefore all of the power it not utilized in moving the boat—part is used in moving the water.
The paddle-wheel is not so efficient in moving a boat as the more modern propeller—or screw, as it is more often called. The screw receives its name from the ordinary metal screw, because its theory of operation is exactly the same. A wood screw, when turned, forces itself into wood. A propeller, when turned, forces itself (and thereby the boat) through the water. A small propeller is illustrated inFig. 34. This is an ordinary three-blade propeller. (The writer prefers the word propeller instead of screw.)
From the drawing, it will be seen that the propeller-blades are mounted at an angle. This angle of the blades causes them to force water back as they cut through it when the propeller is revolving. This forcing of the water back tends to produce a forward motion of the propeller, and in this way the boat on which the propeller is mounted moves through the water. The propeller iscaused to revolve by a steam-engine, steam-turbine, or gasolene-engine, as shown inFig. 35. Longer boats have more than one propeller. A boat that has two propellers is called a twin-screw boat. A boat driven with four propellers is called a quadruple-screw boat.
When a machine screw is turned around just once, it moves forward a certain distance, as a glance atFig. 36will show. The distance the screw moves forward will depend entirely upon the distance between the threads. The distance between the threads is called the pitch of the thread. If the threads are1/32inch apart, then the screw will move1/32inch every time it revolves.
If a propeller acts in the same way as a screw, then it too must have a pitch. The pitch, or the distance that a propeller will advance in one revolution, is measured in inches. A propeller with a pitch of ten inches should move ten inches through the water at each revolution. However, there is a certain amount of "slip," and a propeller does not actually advance the distance that it should theoretically. The pitch of a propelleris really the distance it would advance in one revolution if it were revolving in an unyielding or solid substance.
To make a simple propeller, first cut out of thin sheet brass three blades as shown atA,Fig. 37. Sheet brass with a thickness of1/32inch is very suitable for this purpose. Next, a block, as shown atB, is carefully carved out so that the propeller can be hammered down into the depression. The same block is used for the three blades, so that each will have the same curvature. The block should be cut from oak, since this wood will not split or lose its shape when the forming is done.
The hub is made next. This is shown atC,Fig. 37. The hub, of brass, is made according to the stream-line method. It is filed to shape from a piece of round brass stock. A hole runs lengthwise in the brass, as shown, and a set-screw is used to hold the hub of the propeller-shaft. The method of cutting the slots in the hub is shown atD,Fig. 37. The hub is clamped between two boards placed in the vise, and a hacksaw is used to cut a slot in the hub. The hub isthen turned around one third of a revolution, and another slot cut, using the same saw-marks in the boards, so that the angle of the second slot will be the same as the first one. The third slot is cut in the same manner. The three blades that were cut out are now fastened in these slots and held there by solder. This completes the propeller and it is now ready to be fastened upon the propeller-shaft.
Let us consider the general method of putting the propeller-shaft in place. The young boat-builder will readily understand that it would be very impractical merely to bore a hole in the hull of the boat to put the propeller-shaft through. In this way water would surely leak into the hull and the boat would sink in a short time. Some method must be evolved to keep the water out of the hull, and yet allow the propeller-shaft to revolve freely.
The propeller-shaft is arranged within a brass tube, as shown atFig. 38. The brass tube should be about1/8inch larger in diameter than the propeller-shaft. A little brass bushing must also be arranged at each end,as shown. When the propeller-shaft is mounted in place in the tube, there will be a space between it and the tube. Before the propeller-shaft is put in place it is well smeared with vaseline, and when it is placed in the tube the space between the shaft and the tube will be completely filled with it. This will prevent water from entering. Owing to the fact that vaseline is a soft, greasy substance, it will not prevent the rotation of the propeller-shaft. The brass tube is placed through a hole bored in the hull of the boat. The hole should be a trifle smaller than the diameter of the brass tube, so that the tube can be forced into the hole.
Fig. 39
One of the simplest methods of propelling a boat is by means of rubber bands. Such a boat is shown inFig. 39. This is a small wooden hull fitted with a two-blade propeller. The propeller is shown atFig. 40. It is cut in a single piece and held to the propeller-shaft merely by a drop of solder since there will not be much strain upon it owing to the low power of the rubber-band motor. The opposite end of the propeller-shaft is bentinto a hook, and the rubber bands run from this to another hook placed at the bow of the boat. The rubber bands may be similar to those employed by model airplane builders. The motor, of course, must be wound up by turning the propeller around until the bands become twisted into little knots, as shown atFig. 39. Boats driven by rubber bands cannot be very large unless a great number of rubber bands are used. Even then the power is short-lived. However, building a few small boats driven by rubber-band motorswill do much to teach the young boat-builder some valuable lessons in boat construction.
Probably the best method of propelling model boats is the electric method. By building a boat large enough to accommodate two dry batteries or a small storage battery and a little power motor, a very reliable method of propulsion is made possible. The boat must have sufficient displacement to accommodate the weight of the dry-cells and storage battery. A boat two feet long, with a beam of 41/2inches, is large enough to accommodate one dry-cell and a small motor, providing the fittings of the boat are not too heavy.
A suitable power motor for small boats, which will run with either one or two dry-cells, is shown inFig. 41. The connections for the motor are given clearly inFig. 42, and a suitable switch to control the motor is shown atFig. 43.
Owing to its greater power, the storage battery is to be preferred. Dry-cells are extremely heavy and occupy considerable space. They are also costly, since they donot last long and cannot be worked too hard unless they polarize.
Fig. 41
A very suitable method of mounting an electric motor is illustrated inFigs. 44and45. It will be noticed that the motor is inverted. A small pinion or gear is mounted upon the armature-shaft of the motor. A larger gear (about three times the diameter of the small one) is placed upon the propeller-shaft. This gives a speed reductionof three to one. It will be seen that the propeller-tube is strapped within a strip of brass to a small cross-piece nailed to the bottom board of the hull. The hull is of the built-up type, and the other three boards that go to make it up are not shown. When the three boards are glued in place, a brass strip is run across the top board and the base of the motor is screwed to this. This holds the motor rigidly in place so that it will not move when the power is turned on. The brass strip used should have sufficient thickness to hold the motor rigid. It will also be seen that the motor is tipped slightly so that it will come in line with the propeller-shaft.
Fig. 46
It is not always possible to obtain small gears. For this reason the model boat builder may find it necessary to use a different method of fastening the propeller-shaft to the motor. A very good method of doing this is shown inFig. 46. Here a coiled wire spring is used. This is wound to shape on a rod, and a drop of solder holds it to the propeller and motor shafts. In the method of propulsion shown inFig. 44the armature-shaft of the motor must be perfectly in linewith the propeller-shaft, or the gears will bind and unsatisfactory operation of the motor will result. With the little spring the motor will not have to be mounted exactlyin line with the shaft, and it will also be possible to mount the motor standing up. Of course, if the motor is mounted in this way it will be necessary to make the propeller-shaft longer, as is shown inFig. 47.
Still another method of driving the propeller is illustrated inFig. 48. This method is so simple that the author feels explanation to be unnecessary.
Clockwork can often be employed for propulsion purposes, but this method is not very satisfactory. It is also very difficult to obtain suitable clockworks to install in a boat. Oftentimes it will be possible to salvage the works of an old alarm-clock, providing the main-spring is intact. It is a very easy matter to mount the clock-spring and connect it to the propeller. Any one of the aforementioned methods can be employed.
Steam propulsion has its advantages; but, on the other hand, the writer is not inclined to recommend it as strongly as the electric method for reliability. Of course, steam is a more powerful agency in the propulsion of small boats and thereby greater speed is attainable by its use.
Fig. 49
Here is a very simple small power plant suitable for driving boats up to 31/2feet in length. The boiler is shown inFigs. 49and50. The method of assembling the boiler is pictured clearly inFig. 49. A brass or copper tube about 21/2inches in diameter is used. Two end pieces are cut to shape and forced into the boiler ends. A hole is drilled in the center of these pieces before they are put in place. After the end pieces are forcedin place solder is carefully flowed around their edges. The brass rod is then threaded at each end and placed concentrically within the boiler, as shown inFig. 49. A nut is placed on each end of this rod and tightened. The nut is then soldered in place. This brass rod, called a stay-rod, prevents the end of the boiler from blowing out when the steam pressure has reached its maximum value. Three holes are drilled in the brass tube, as shown. One is to accommodate the steam feed-pipe that goes to the engine; another is for the safety-valve, and still another for the filling plug. The safety-valve and filling plug are both shown inFig. 51. The little spring on the safety-valve is adjustable, so that the valve can be regulated in order to prevent it from blowing off at pressures lower than that at which the engine operates.
Fig. 52
Fig. 53
A suitable firebox for the boiler is shown clearly inFig. 52. This is cut to shape from stovepipe iron and held together with small rivets. Holes should be punched or drilled in the side of the firebox to give the burner a sufficient supply of air. The burner isillustrated clearly inFig. 52. The fuel-tank can be made from an ordinary tin can with the cover soldered on, and a hole made for a cork by means of which it is filled with denatured alcohol. A little pipe runs from the fuel-tank to the burner. It is advisable, if possible, to place a small valve in this pipe to cut off the fuel supply when necessary. The only other method of putting the burner out would be to stand it on its end. The burner consists of a rectangular tin box with a top cut out as illustrated. A piece of brass or copper gauze is placed in the top. Asbestos wool is used to fill the can, and the alcohol is drawn into the wool by capillary attraction, where it burns with a steady hot flame at the surface of the copper gauze. Inthe corner of the can near the feed-pipe another small piece of copper gauze is soldered as shown. This covers up the feed-pipe entrance so that the asbestos will not plug up the pipe.
Fig. 54
The engine to be used in connection with the boiler just described is shown inFig. 53. This is a very simple engine of the oscillation type, and there should be little trouble in making it. A more mechanical drawing of the engine is shown inFig. 54. The details of the engine are shown inFig. 55.
Fig. 55
The cylinder of the engine should be made first. This is made from a piece of brass tubing with an internal diameter of3/4inch. Two end pieces, or a cylinder-end cover andcylinder head, must be cut to fit inside the cylinder. These should be cut to shape from1/16inch brass, and a hole drilled in the cylinder head1/8inch in diameter to accommodate the piston-rod. The cylinder head is then soldered in place. The cylinder-end cover should be left until the piston-rod and piston are made.
The piston head is cut to shape from a piece of3/16-inch sheet brass, or it can be cut from a piece of3/4-inch round brass with a hacksaw. The piston-rod is soldered into a hole in the piston-head. A small square piece of brass is placed on the opposite end of the piston-rod to act as a bearing. This little piece is cut and drilled as shown in the drawing. Before it is soldered in place on the piston-rod the cylinder-end cover should be placed on the rod. Both the piston and the cylinder-end cover can then be placed inside the cylinder, and the piston-end cover is soldered in place. Before final assembling the piston should be made to fit nicely into the cylinder. This can be brought about by applying emery cloth to the piston-head until it slips nicely into the cylinder with little orno play. Thus a steam-tight fit is made, and this contributes greatly to the efficiency and power of the engine.
Fig. 56
The cylinder blocks are shown inFig. 55. These are cut and brought to shape with a hacksaw and file. With a half-round file one side of one of the blocks is filed slightly concave, so that it will fit on the outside of the cylinder. Two1/8-inch holes are drilled in this piece as shown in the drawing. The hole at the top is the steam entrance and exhaust for the engine; that is, when the cylinder is at one side steam enters this hole, and when the crank throws the cylinder over to the other side steam leaves through the same hole after having expanded in the cylinder.This cylinder block is soldered to the piston as shown inFig. 56. The pivot upon which the cylinder swings is then put in place in the hole at the bottom of the block. Solder is flowed around the pivot to hold it securely in place.
The second cylinder block is now finished according to the drawing. This has two holes1/8inch in diameter bored in it. One of these holes is the steam inlet and the other the exhaust. When the cylinder is at one side of its stroke the hole that was bored in the top of the steam block which was soldered on the cylinder is in line with the inlet hole in the block under consideration. Steam then enters the cylinder and forces the piston down. This turns the crank around, and the crank in turn pulls the piston over to the opposite side, so that the hole in the first piston block of the cylinder now comes in line with the exhaust hole on the second cylinder block. The steam in the cylinder escapes and the same operation is repeated over again. Of course, it must be understood that this steam admission and exhaust takes place very rapidly. The hole in the secondcylinder block, which goes over the pivot, must be made a trifle more than1/8inch in diameter, so that it will slide freely over the pivot.
The engine is mounted on a very simple frame, which is a piece of1/16-inch brass cut and bent as illustrated. After it is cut and bent to shape the second cylinder block is soldered in place. The cylinder can then be mounted. It will be seen that the pivot goes through both the second cylinder block and the engine standard. A small spring is placed over the protruding end of the pivot and a nut put in place. By turning this nut the pressure on the face of the two cylinder blocks can be adjusted, and the model engineer must always remember that the pressure on these springs must be greater than the steam pressure in the feed-pipe. Otherwise the steam pressure will force the cylinder-block faces apart and steam leakage will result. On the other hand, the pressure of the spring should not be too great, since that would interfere with the free movement of the engine cylinder.
Nothing now remains to be made exceptthe crank and the flywheel. The crank revolves in a small brass bearing which is soldered in place on the engine standard. It will be seen that the sheet brass that makes up the engine standard is not thick enough to offer a good bearing for the crank. The crank is bent to shape from a piece of1/8-inch brass rod, and the author advises the builder to heat the brass rod red-hot while the bending is done. This will prevent it from fracturing, and will also permit a sharp bend to be made.
The flywheel is a circular piece of brass 1 inch in diameter. Its center is drilled out and it is soldered to the crank as illustrated inFig. 54. Two other holes1/8inch in diameter are drilled in the flywheel as illustrated, and two small brass pins are cut out from1/8-inch brass rod and forced into these holes and then soldered. These provide a method of driving the propeller-shaft that is shown very clearly atFig. 57.
The steam feed-pipe that runs from the boiler to the engine can be of small copper tubing. It may be necessary to mount theengine on a small block, as shown inFig. 53. After the steam in the boiler has reached a sufficient pressure the engine crank should be given a couple of twists in order to start it. Before operating the engine a little lubricating oil should be run into the cylinder through the inlet or exhaust ports. The cylinder should always be kept well lubricated. The contacting faces of the cylinder blocks should also be kept lubricated.
Caution.Always keep water in the boiler. Never permit it to run dry, as this would cause a boiler explosion. When the engine is started and cannot be made to run, take the burner from under the boiler so that steam will cease to be generated. With the safety-valve the model boat builder need have little fear of an explosion. Nevertheless the foregoing directions should be carefully adhered to.
THE little electric launch to be described is of very simple construction, and when finished it will provide the builder with a very shipshape little model from which he will be able to derive a good deal of pleasure. It has a speed of from 21/2to 3 miles an hour when equipped with dry batteries or storage batteries. The hull is of the Sharpie type, and this offers very little trouble in cutting out and assembling.
The general appearance of the boat and hull will be gathered from the drawings. The pieces necessary to assemble the hull are shown inFig. 58. Only five pieces are necessary: two side pieces, a stern piece, a bow piece, and a bottom piece. The length of the boat over all is 40 inches with a 7-inch beam. The widest part of the boat is 1 foot 10 inches from the bow.
After the pieces that form the hull are cut they are thoroughly sandpapered to produce a smooth surface. The heavy imperfections in the wood can be taken out with coarse paper, and the finishing can be done with a finer paper. It is understood that sandpapering should always be done with the grain, never across the grain. The sides of the boat are cut about1/4inch thick, but they are planed thinner in places where the bend is most pronounced. The side pieces are 23/4inches deep at the stern and 21/4inches at the stern. There is a gradual curve from the bow to the stern, which is more marked toward the head.
The stern piece is thicker than the side pieces, being made of1/2-inch wood. It is cut to the shape shown atFig. 58, and beveled along the bottom edge to enable it to be fixed on the slant. The bow piece is a triangle 23/4inches in length.
After the parts are thoroughly finished with sandpaper the stern piece is fixed in position. In making all the joints on the boat the builder should see that plenty of fairly thick paint is run in while the joint isbeing screwed up. This will help greatly in making the boat water-tight. Plenty of3/4-inch brass wood-screws are used in assembling the hull. All the holes for the wood-screws should be countersunk so that the heads will come flush with the surface of the hull. Now one of the sides should be screwed to the stern piece, at the same time bending the bottom and side to meet. This is done gradually, inch by inch, and screws are put in place at equal distances. When the bow is reached, the side piece is beveled to fit the bow piece, which should already have been screwed into place. The other side of the boat is treated in a similar manner, and the young worker should take care to keep the side and bow piece perfectly square and upright. This may sound easy on paper, but it will be found that a good deal of care must be exercised to produce this result.
After the hull has been assembled it is given a good coat of paint inside and out. When the first coat is dry the holes left by the screw-heads are carefully puttied over, and the hull is given a second coat of paint.This procedure will produce a perfectly water-tight hull.
Fig. 58
The stern tube is3/8inch, outside diameter. A hole is bored in the bottom of the boat to receive the stern tube. This job must be done cautiously; otherwise the bottom of the boat may be ruined. It is best to screw a substantial block to the inside of the boat. This block should be cut to fit the bottom and will act as a support for drilling. Itwill also help greatly to make a water-tight joint around the tube. The distance from the point where the stern tube passes through the bottom to the stern should be about 121/2inches. The stern tube should be mounted as nearly parallel with the bottom as possible, since on this depends the speed of the boat. As the angle of the propeller-shaft increases, the speed of the boat will decrease. In drilling the hole the boat-builder should be careful to keep the drill running along the central line of the boat.
As before mentioned, the stern tube is a piece of brass tubing3/8inch in diameter and 8 inches long. It is filed square at both ends, and a brass plug is fastened with solder in each end. The tube is then filled with melted vaseline, which is allowed to cool. The hole in the hull around the tube is then well smeared with thick paint. When this is done, a layer of red lead or putty is placed around the joint both on the inside and the outside of the boat.
While the putty is drying the spray-hood or turtle-deck can be made. This is bent to shape from a piece of tinplate and extendshalf way down the boat. When the turtle-deck is finished, it is best to lay it aside, before finally fastening it in place, until the entire boat is completed.
The wooden part of the deck is made of1/8-inch wood and scribed with a sharp knife to represent planking. This method of producing planking was described in detail in Chapter II.
Toward the stern of the boat and just behind the motor a hatchway is fitted to give access to the batteries and starting switch.
The finished Sharpie hull without its driving batteries or motor should weigh about 1 pound 3 ounces. The hull being finished, let us consider the electric propelling equipment.
A1/8-inch cold-rolled steel driving or propeller-shaft is used. The shaft is 13 inches long and a gear-wheel 1 inch in diameter is fixed to one end of this shaft. This gear-wheel meshes with a brass pinion on the motor-shaft. This forms a 31/2to 1 reduction gear, which produces a greatly increased speed of the boat. The other end of the propeller-shaft rests in the skeg bearing. Inthis present case this consists of a tube about1/2inch long, which is made for a revolving fit on the propeller-shaft and supported by a sheet-metal bracket. This is shown inFig. 63. The end of the propeller also revolves adjacent to the bearing in the skeg.
GETTING READY FOR A TRIPGETTING READY FOR A TRIPHeating the blow-torch to a point where it will burn automatically
The propeller is a three-blade affair with a diameter of 21/4inches. It is attached to the propeller-shaft with a set-screw. The motor is a very simple type obtainable in the open market. It is similar to one shown inFig. 41. As before mentioned, either dry or storage batteries may be used as a source of current. The writer strongly advises the use of storage batteries if possible. The initial cost of these batteries is greater than that for dry batteries; but, on the other hand, the small storage battery can be charged repeatedly and will outlast many dry batteries. If the boat is used much the storage battery will probably be the more economical of the two.
The steering gear of the boat is very simple. The rudder works in a bearing that is screwed to the stern piece. The end of the rudder-shaft is tapped, and a brass screw isused to clamp it in position after setting it with the fingers. The rudder-shaft is a3/4-inch brass rod. The lower end of this rod is slit with a hacksaw and the rudder is placed in this. Solder is then flowed along the joint.
ALL READY TO GO!ALL READY TO GO!A little boat with steam up, ready for a trip when her owner releases her
Of course, the builder may paint his boat whatever color he may select; but a maroon hull with a white-enameled spray-hood or turtle-deck makes a very pleasing combination.Fig. 60shows a rough plan of the general arrangement of the power machinery.Figs. 61,62and63will do much to give the reader a clear idea of the method of construction which could not be gained by reading a description.
Fig. 60
Fig. 61
The general appearance of the boat can beimproved materially in many ways. For instance, a little stack or ventilator may be added to the turtle-deck, and a little flag-stick carrying a tiny flag may be placed on the bow and on the stern.
Fig. 62
The motor current should be turned on only when necessary, for dry-cells deteriorate rapidly when in use, and small storage batteries quickly lose their charge, although they will last much longer than dry-cells and give much better service.
THE steam launchNancy Leeis an attractive little craft when finished and it is capable of attaining considerable speed. It is really designed after the cruising type of motor-boats. This type of boat is particularly adaptable for simple model-making, owing to the elimination of awkward fittings. The power machinery is of very simple construction and presents no real difficulty.
The following materials are necessary to construct theNancy Lee:
Large wood block for hull.Thin white pine for deck, etc.Sheet-metal tube, rod and wire for the boiler, engine, etc.Lamp-wick, paint, screws, and bradsMiscellaneous fittings
The actual expense necessary to construct the boat is very small.
Having obtained the block for the hull, you are ready to start work. The hull, when planed on all sides, should be 30 inches long, 61/2inches wide, and 33/4inches deep. A center line is drawn down the length of the hull, and five cross-section lines are drawn at right angles to the center line 5 inches apart. On these lines the builder should mark off the greatest lengths of the boat, taking the dimensions from the half-breadth drawing shown inFig. 64. It will be noted that the deck is wider than the L. W. L. forward and narrower than the L. W. L. at the stern. The block should be cut to the widest line on the half-breadth part.
Fig. 65
The half-widths inFig. 64are drawn each side of the center line on the block. The block will be cut out to this line andplaned up as true as possible. The builder should then project the section lines with a set square on each side of the boat, mark off the profile from the sheer plan,Fig. 65, and cut the block to this line, afterward planing it up true.