Boys' Book of Model Boats Part 12

This process should be repeated three times.

Three coats of varnish should be given to the under side of the deck after the pieces have been glued on, and when dry the deck can be fitted, 3/8-inch veneer pins being used for fixing on, and care being taken to get it true to position. A center line is drawn down the under side of the deck, and marks made to correspond at the stern and transom on the sh.e.l.l.

The planking lines on the deck can be drawn to suit your fancy, India ink and a draftsman's ruling pen being used to do it, afterward applying two coats of carriage varnish.

To paint the hull, white lead and dryers, in the proportion of 5 to 1 by weight respectively, should be dissolved in turpentine, a few drops of linseed oil being mixed to make it work freely.

Have this about the consistency of milk, and, after straining, give the hull about eight coats, one every twenty-four hours, rubbing each down when dry with No. 00 sandpaper. Keep the joint representing the load water-line always in sight by penciling over after each coat of paint is dry.

When a sufficient body of paint has been applied, the colors can be applied. Enamel is best for this. Stick strips of gummed paper around the hull at the water-line, and paint up to the edge. When the paint is dry the paper can be soaked off, the paper being again applied, but reversed for the other color. If you can use a lining brush the paper is not necessary for the second color.

While the painting is going on, spars, sails, and fittings can be made. As the spars have to be varnished, it is best to make them first. Pine should be used, and after cutting strips of suitable length and diameter, plane them square in section. With the batten draw on the face the amount of taper to be given, and plane down to this line, still keeping the spar square in section. This having been done, the corners are planed off carefully until the spar is octagonal in section, when it is easy to make it perfectly round with sandpaper by rubbing with the paper rolled around the stick. The diameter of our mast is 1/2 inch parallel until the hoist of the fore triangle is reached, tapering from there to 1/4 inch at the masthead or truck. The boom is 1/4 inch at the gooseneck, thickening to 3/8 inch where the main-sheet is attached, down to 1/4 inch at the outboard end. The jib-boom is slightly less than 1/4 inch parallel.

All spars should be treated with clear size and fine sandpaper before varnishing. This will prevent discoloring by the latter, and will also allow the India ink markings to be made, which latter will be a guide for the tr.i.m.m.i.n.g of the sails.

In order that any yacht, model or otherwise, may be able to perform her best, it is essential that she should have well setting sails. In fact, in a model a badly setting sail will sometimes even be enough to prevent her going to windward at all. By well setting sails we mean sails that are naturally flat and not made so by straining them out on the spars. Light material, such as cambric or light union silk, is best for this purpose, but not a material that has any dressing in it.

This particular sail plan is very easy to mark out. Lay your material out on a table or smooth surface and pin it down with drawing-pins, sufficiently stretching it so as to pull out any creases. The length of the back edge of the mainsail (which is called the leech) is measured off 1-1/4 inches inside the edge of the cloth, and a curve struck as ill.u.s.trated. The other two sides of the mainsail are then laid off and pencil lines drawn. You will note that allowance must be made for hemming the back edge of the mainsail. If your sewing-machine has a hemmer, find out how wide a hem it makes (the smaller the better), and make allowance accordingly, twice the width of the hem being necessary. Much depends upon the tension at which the machine is set, so be careful that the latter is sufficiently slack so that it does not draw up the material.

The jib is marked out in the same manner, and, as ill.u.s.trated, the lines representing the positions of the batten sleeves are drawn. The batten sleeves are small pockets into which thin pieces of cane (called battens) are inserted to help the sail to set nicely. Unless the sail is a good cut to begin with, however, the insertion of these battens will never make it right. The sails should now be cut out with a sharp penknife or scissors, care being taken not to pull the cloth, and especially not along the edges that run across the threads. You then hem the backs and also the foot of the jib. The batten sleeves (which should be of white satin ribbon about 3/8 inch in width) should now be sewn on by st.i.tching down along the extreme edge to the line drawn, and then down the other edge, the ends being left open. A strip of narrow tape is sewn across the foot of the jib-sail to take the strain of the pull, the part of the jib contained by the curve of the foot and the tape being known as the bonnet of the jib.

To prevent the edges of the sails (other than those hemmed) being stretched, you bind them with good tape. The tape is first folded and creased by rubbing over an edge. The end of the tape is then turned in. Take a corner of the sail and place it inside the fold of the tape, care being taken to get the raw edge right up against the crease. The needle of the machine should then be lowered through it as near to the edge of the tape as practicable, taking care that it goes through both edges. Keeping a slight pull on the binding, arrange the cloth in it without pulling the edge.

Put the foot of the machine down and sew it, afterward raising the foot again and proceeding as before right around the raw edges of the sail, leaving the needle down each time the foot is raised. Do not sew where a batten sleeve pa.s.ses under the binding, as you will require the former left open to allow the batten to pa.s.s into the fold of the binding. The rings for putting up the luffs of the jib- and main-sail are made by winding a piece of thin bra.s.s or German silver wire around a steel rod (the spokes used in the keel being suitable for the latter) and sawing down to divide them. A small eyelet should be put in each corner of the sails, and others s.p.a.ced evenly at about 2-1/2 inches apart along the boom and about 5 inches apart along the mast, for lacing on. An extra row of st.i.tching may be run down the outer edge of the binding to smooth it down.

The simpler the fittings of a model that is required for practical sailing, the better. They should be as light as practical. Aluminum is not advisable for fittings when the boat is to be sailed in salt water.

[Ill.u.s.tration: FIG. 157]

The bowsprit fittings, which are known as the gammon iron and heel plate (Figs. 157, 158), are made by soldering pieces of bra.s.s tube (cut to suitable size and shape) onto pieces of triangular sheet bra.s.s, as ill.u.s.trated. The horses can either be of wire with the ends turned to suitable shape and fitted with one screw, or they can have plates for two screws, in which case the wire is either threaded and screwed into the plate or silver-soldered to it. Silver-soldering is done with a blow-pipe. The flux used is borax made into a thin paste with water. Silver-solder is bought in small sheets, and a few cents' worth will go a long way if used properly. Cut small pieces about 1/8 inch by 1/16 inch, and, after painting the part to be soldered with your paste borax with a very small brush, pick up the solder with the tip of the brush and put it in position. It will then run around the joint when the metal is raised to sufficient heat.

[Ill.u.s.tration: FIG. 158]

The hatch-rim is made by cutting a strip of thin bra.s.s 1/4 inch in width, the length being the circ.u.mference of the oval. The two ends are brought together and silver-soldered. Cut out the oval in a piece of very thin bra.s.s and fit in your oval strip so that the flat is just in the center of it. This can then be sweated around with an ordinary soldering-iron, the flat being trimmed down afterward with the shears to leave a f.l.a.n.g.e 1/4 inch in width, the latter being drilled to take 1/4 inch No. 0 round-head screws.

[Ill.u.s.tration: FIG. 159]

[Ill.u.s.tration: FIG. 160]

[Ill.u.s.tration: FIG. 161]

The deck fitting for the mast, (Fig. 159) is made in much the same way, a piece of tube being used instead of cutting a strip of bra.s.s. To receive the heel of the mast a fitting known as the mast-step must be made and fitted. This, of course, must be done before the deck is put on.

The step is made from two pieces of bra.s.s, each about 1/32 inch in thickness, 1 inch long and 1/2 inch wide. One is hard-soldered on edge down the center of the other to form something like a T girder. A slot, as ill.u.s.trated, is cut in the upright piece with a ward file, and holes drilled in the flat for s.c.r.e.w.i.n.g down on the inside of the boat. A ferrule of bra.s.s tube is fitted to the heel of the mast, a cut of suitable size being made in it to receive the upright of the step. A hole should be drilled through the heel of the mast at right angles to the slot, and a wire pa.s.sed through and riveted, the latter being of suitable thickness to be received by the slot in the step.

[Ill.u.s.tration: FIG. 164]

[Ill.u.s.tration: FIG. 163]

[Ill.u.s.tration: FIG. 162]

The rudder-blade (Fig. 162) is made from a piece of sheet bra.s.s fitted to a tube, the latter being an easy fit into the stern-tube already fitted.

The blade can be soldered onto the tube. The pintle on which the rudder fits and swings is a strip of bra.s.s, the width of the after fin, a wire pin being hard-soldered in to fit up into the rudder.

The pintle (Fig. 163) should be fitted before the painting is started.

In the steering gear, instead of a quadrant, as the fitting on the rudder-head of the "Braine"

gear is called, you fit an ordinary tiller (Fig.

164) by bending a wire to suit your fancy and soldering it on to a collar made from a piece of tube that will just sleeve on the outside of the rubber-tube, which latter is fixed by drilling a hole right through it and the rudder head, and fitting a tapered pin.

[Ill.u.s.tration: FIG. 165]

[Ill.u.s.tration: FIG. 166]

The steering-gear rack (Fig. 165) by which the amount of helm is adjusted is made from a strip of bra.s.s cut with lugs which are bent up at right angles as ill.u.s.trated. This need only be of thin sheet metal, as the strain is very small.

For running before the wind, separate lines are used, two in number, as ill.u.s.trated, and the amount of helm is governed by the distance away from midships that the lead is moved. For instance, if the lead is placed amidships, the pull will simply keep the rudder dead straight, whereas if placed on the deck edge it will allow the maximum amount of angle.

Your bowsers can be made from pieces of toothbrush handle or from bra.s.s or German-silver wire. Very efficient bowsers can be made from aluminum tube cut in sections about 3/16 inch long, with three holes drilled in each piece around its periphery.

Plaited bobbin cotton should be used for the cordage, as it does not curl up when wet.

If you decide to fit the Braine steering gear, a spur or b.u.mpkin, as it is termed, must be fitted to take the rubber centering line.

APPENDIX

BOYS' DICTIONARY OF MARINE TERMS

=Abaft.= Behind; toward the stern.

=Abeam.= At right angles to the side and in horizontal plane.

=Aft.= Toward the stern.

=After-body.= Between amidships and stern.

=Aloft.= Overhead; on the yards or in the upper rigging.

=Amidships.= The middle part of a vessel.

=Anchor.= Instrument for holding vessels at rest in the water. Made of iron.

=Athwart. Athwartships.= Across; from side to side.

=Ballast.= Material used to load the ship, for stability or submerging purposes.

=Barge.= General name for vessels built for towing.

=Bark.= Three-masted vessel, square-rigged on the fore- and main-masts, and fore-and-aft rigged on the mizzen.