The Boy Mechanic Part 108

** A Monoplane Weather Vane [390]

The toy windmill or weather vane shown in the sketch is made to represent a Bleriot monoplane.

[Ill.u.s.tration: Wire and Sheet-Metal Vane]

The propeller is turned by the wind. The frame is made of heavy wire and connected with straps of tin. The construction is plainly shown in the ill.u.s.tration. The windmill vane can be made in any size to suit the builder.

--Contributed by W. C. Bliss, St. Louis, Missouri.

** How to Make a Minnow Trap [390]

Gla.s.s minnow traps that will give as good service as those purchased at the tackle store can be made without difficulty. If a trap should be banged carelessly against the side of the boat or some other obstruction and smashed, instead of spending several dollars to replace it, a half hour's time will turn out a new one just as good, says a correspondent of Outing.

A trap of this kind can be made from an ordinary fruit jar such as used in putting up preserves, either of one or two-quart capacity.

A one-quart jar gives good results, but if the bait to be caught is of fairly large size, the two quart size may be used. As the jars have the same style top they can be used interchangeably with one mouthpiece.

The mouthpiece is made of a round neck bottle of which the gla.s.s is colorless and rather thin. If the neck of the bottle is cut at the right point, it makes a gla.s.s funnel that will just fit into the fruit jar. The funnel forms the mouth of the trap. Put the neck of the bottle into the fruit jar and mark the gla.s.s with a file where the bottle and jar meet. Make as deep a cut as possible with a file around the bottle on the mark and place two turns of a yarn string saturated in kerosene around just below the cut when the bottle is standing in an upright position. Set fire to the string and turn the bottle from side to side to distribute the heat evenly, then when the string has burned out, plunge the bottle in cold water and it will separate on the cut.

Bind some copper wire around the neck of the jar so that three ends will project 1/2 in. or more. These are bent down over the funnel when put into the jar, forming clamps to hold it in place.

The copper wire can be bent many times in emptying or baiting the trap without breaking.

Two copper wire bands are tied tightly around the jar about 3 in.

apart. They should be twisted tight with a pair of pliers and the ends joined, forming a ring for attaching a cord.

For catching "kellies" or "killies," bait the trap with crushed clams or salt-water mussels and for fresh water s.h.i.+ners use mincemeat or bread crumbs and do not spill any bait outside of the trap. Leave the trap down ten to fifteen minutes and when resetting it after emptying, put back one or two of the victims, as the others enter more readily if they see some of their companions ahead of them.

** A Remedy for Leaking Fountain Pens [390]

Fountain-pen leaks may often be prevented by uns.c.r.e.w.i.n.g the joint and lightly smearing the screw with vaseline. This also makes it easy to unscrew the joint for filling.

** Kites of Many Kinds and How to Make Them [391]

One of the prettiest of all is the b.u.t.terfly kite. To make this get two thin kite sticks of equal length. Bend each in an are, tying one end of a strong string to one end of each stick and the other end of the string to a point about 3 in. from the other end of the stick. This leaves one end of each stick free, hooking over the hemisphere described by the thread and the stick. Now tie another thread to

[Ill.u.s.tration: Boy Kite]

each of these free ends and tie the other end of the thread to a point near the other end of the stick, corresponding with the distance from the end at which the first strings were tied on the opposite side. This done, you should have two arched frames, each an exact counterpart of the other in size, curvature and weight.

Now fasten the two frames together so that the arcs will overlap each other as shown in the sketch. Bind the intersecting points securely with thread. To make the b.u.t.terfly's head, secure two heavy broom straws or two short wires, and

[Ill.u.s.tration: Girl Kite]

attach them to the top part of the wing frames near where the sticks intersect, so that the straws or wires will cross. These form the antennae, or the "smellers." Then select the color of paper you want, yellow, brown, blue, white or any other color; lay it on a flat surface and place the frame on top of it, holding the frame down securely with a weight. Then with a pair of scissors cut the paper around the frame, leaving about a 1/2-in. margin for pasting. Cut slits in the paper about 2 in. apart around the curves and at all angles to keep the paper from wrinkling when it is pasted. Distribute the paste with a small brush and make the overlaps a little more than 1/4 in. wide and press them

[Ill.u.s.tration: b.u.t.terfly Kite]

together with a soft cloth. When the kite is dry decorate it with paint or strips of colored paper in any design you may fancy. The best effects are produced by pasting pieces of colored paper on top of the other paper. Black paper decorations show up to fine advantage when the kite is in flight. Attach the "belly-band" to the

[Ill.u.s.tration: Frame for Girl Kite]

curved sticks by punching a hole in the paper in the same manner as it is attached to the common hexagonal or coffin-shaped kite.

With a tail, your kite is ready to fly. Another interesting design is the boy kite. With light colored coat and vest and gay striped trousers, the kite standing high in the air always attracts attention and affords splendid sport for the American youth in springtime.

In making a boy kite it should be remembered that the larger the boy is the better he will fly. To construct the frame, two straight sticks, say 3-1/2 ft. long, should serve for the legs and

[Ill.u.s.tration: Frame for Boy Kite]

body; another straight stick forms the spine and should be about 2 ft. 4 in. long. For the arms, get a fourth straight stick about 3 ft. 3 in. long. Make the frame for the head by bending a light tough stick in a circle about 7 in. in diameter. Bind it tightly with a strong thread and through its center run the spine. Then tack on the arm stick 3 in. under the circle so that the spinal column crosses the arm stick exactly in the center. Wrap tightly with strong thread and tack on the two sticks that are to serve for the legs and body. The leg sticks should be fastened to the arm stick about 6 in. on either side of the spinal column, and crossed so that the other ends are 3 ft. apart. Tack them and the arm stick together at the point where they intersect. Small hoops and cross stick of the same material as the head frame should be fastened to both extremities of the arm stick and the lower ends of the leg stick for the hands and feet. See that both hand frames are exactly alike and exercise equal caution regarding the foot frames; also see that the arm stick is at exact right angles with the spine stick and that the kite joints are all firmly tied and the kite evenly balanced; otherwise it may be lopsided. Fasten on the strings of the frame, beginning at the neck at equal distances from the spine, as indicated by the dotted lines in the diagram.

Extend a string slantingly from the arms tick to the head on both sides of the spinal column, and run all the other strings as shown in the cut, being careful that both sides of the frame correspond in measurements.

To cover the kite, select different colors of paper to suit your taste, and after pasting them together, lay the paper on the floor and placing the frame on it, cut out the pattern. Leave an edge of 1/2 in. all around and make a slit in this edge every 6 in. and at each angle; make the slits 2 in. apart around the head. After the kite is pasted and dry, paint the b.u.t.tons, hair, eyes, hands, feet, etc., as you desire. Arrange the "belly band" and tail band and attach the kite string in the same manner as in the ordinary coffin-shaped kite.

The "lady kite" is made on the same principle as the boy kite. The frame may be made exactly as the boy kite and then "dressed" with tissue paper to represent a girl, or it may be made on the special frame, page 81. Remember the dotted lines represent the strings or thread, and the other lines indicate the kite sticks. Be careful with your measurements so that each side of the kite corresponds exactly and is well balanced. Also see that every point where the sticks intersect is firmly tacked and bound.

To cover the kite, first paste together pieces of tissue paper of different color to suit your taste. The paste should be made of flour and water and boiled. Make the seams or overlaps not quite 3/8 in. wide. Lay the paper on the floor, using weights to hold it down, and place the frame of the kite upon it. Then cut out the paper around the frame, leaving an edge of 1/2 in. Don't forget to make a slit in the edge every 6 or 7 in. and at each angle. Around the head the slits are cut 2 in. apart, as in the case of the boy kite. After the kite is dry, paint the paper as your fancy dictates.

To make the breast band, punch holes through the paper, one upon each side of the leg sticks, just above the bottom, and one upon each side of the arm sticks at the shoulder. Run one end of the string through the hole at the bottom of the left limb and tie it to the leg stick; tie the other end at the right shoulder. Fasten one end of another string of the same length at the bottom of the right leg; pa.s.s the string up across the first band and tie the other end at the left shoulder. Attach the kite string to the breast band at the point where the two strings intersect. Tie the knot so that you can slide the kite string up or down until it is properly adjusted. The tail band is made by tying a string to the leg sticks at the bottom of the breast band. Let the string hang slack below the skirt and attach the tail to the center. The same general rules apply in attaching the string and tail to the boy kite.

You can make the lady look as if dancing and kicking in the clouds by making the feet of stiff pasteboard and allowing them to hang loose from the line which forms the bottom of the skirt. The feet will move and sway with each motion of the kite.

** How to Make Rubber Stamps [393]

India rubber, especially prepared for stamp-making, should be procured from a dealer or manufacturer, if good results are to be obtained. As an experiment, it is possible for an amateur to prepare the rubber, but, in such cases, it is always attended with uncertain results. The mixed uncured rubber comes in white sheets, strong, firm and about 1/8 in. thick, and for its manipulation a press is indispensable, but can be home-made.

For the base of the press use a piece of iron, having two holes drilled in it at the middle of opposite sides, through which pa.s.s bolts, letting the thread ends extend upward and counter-sinking places for the bolt heads to keep the under side of the base level. Solder the bolts in place at the base. The upper part of the press, or the platen, is also of iron, cut so it can be swung

[Ill.u.s.tration: Fish Kettle Vulcanizer]

off the bolts, rather than by removing the nuts and lifting it off. String a half dozen nuts, larger than those which screw on, on each bolt, so that when the upper nut on each is screwed to the extent of the thread the pressure will be communicated through the nuts wedged in between the platen and the upper nut. The bolt holes in the platen should be directly over those in the base.

Distance pieces of an exact thickness should be provided for use on the base; these serve to keep the pressure even.

In preparing the mould, if type is to be copied, use rather large type with wide s.p.a.ces and set up with high quads and s.p.a.ces, or the type faces may be filled up by rubbing with either wax, or soap, lightly brus.h.i.+ng off any that remains loose. The type so set should be locked into a frame. This may be made of two pieces of wood bolted together at both ends, or of printer's furniture.

Place it on a flat surface (marble is good, but any perfectly smooth surface will do) and place distance pieces 1/8 in. higher than its upper surface on either side of it. Apply olive oil to the type faces and wipe off any excess. To form the matrix or reverse of the model, take a piece of iron larger than the inscription to be copied, and spread upon it to a depth of 1/4 in, a putty made by mixing plaster of paris and water to the right consistency. By means of a table knife spread the plaster smoothly and then invert the plate upon the model and press down until

[Ill.u.s.tration: Vulcanizing Press for Rubber Stamps]

the distance pieces are struck. Let it set 10 minutes and then remove. If care has been taken the matrix will be perfect. After it has thoroughly dried, preferably in an oven, saturate it with an alcoholic solution of sh.e.l.lac to strengthen it.

Cut a piece of smooth rubber, large enough to cover the matrix, from the sheet, throw this into a box of talc, or powdered soapstone, so that it receives a coating on both sides; dust a little of the powder over the matrix, also. Place the press on a support over a gas burner; or a kerosene lamp, and apply the heat.

Place the matrix on the base of the press, dust off the piece of india rubber and place in the press upon the matrix and screw down the platen. Heat the press to 284 deg. F. and keep s.c.r.e.w.i.n.g down the platen so that the rubber, now soft and putty-like, is forced into every recess of the matrix. A thermometer is not necessary; some rubber always protrudes and the stage of the process can be told from that. At first it is quite elastic, then as the heat increases it becomes soft, then the curing begins and it again becomes elastic, so that, if a point of a knife blade is pressed against it, it resumes its shape when the point is removed. When this takes place it is then thoroughly vulcanized and the sheet can be removed from the matrix. Ten minutes, under favorable conditions, is sufficient time for moulding the rubber. By means of common glue, or bicycle tire cement, fasten the rubber stamp to a wooden handle.

It is possible to dispense with the press in making stamps, where the work is not done in quant.i.ties, and use a hot flat-iron. The matrix is placed on a stove at low heat, the rubber laid on and the hot iron applied. But a few moments are required to mould it.