Kite Making at Home—II
How to Build and Fly the Blue Hill Box, Malay Box Combination and Tetrahedral Cell Kites
H. S. Rinker
(Concluded from June issue)
HAVING progressed thus far, variety can be introduced by making some Blue Hill box-kites. These are named after the Blue Hill Weather Observatory, Massachusetts, where they were originated. They look like Fig. 16.
Make 4 sticks ½ in. square, but otherwise proceed as described for the Malay kite. All kite sticks must be worked out in this manner to assure the absence of cross or twisted grain. Otherwise they may fail when you least expect it, and make more trouble than if made right at first. Several ways of bracing have been used, but the writer has had best results from the one shown. Put the frame together as indicated in Fig. 18.
Two of these side frames are needed for each kite. For bracing, nothing is better than a bamboo pole, about y in. in diameter. Take apiece of this about 4 ft. 6 ins. long and rip it exactly in half, from each end until about 4 ins.
in the middle remain uncut. Wrap this part with wire and solder. Then it will appear as shown in Fig. 19. Spread it out on your bench and hold with wire nails as illustrated in Fig. 20.
Now at points marked A, cut a shoulder, so that you can spring the brace into the holes in the hardwood strips. Take two strips of cambric 19 ins. wide and hem both sides, making them 18 ins. when hemmed. Pull out the puckers and square one end. Measure
12 ft. i in. and square the other end. Sew up with a half-inch seam. You now have two endless loops, each exactly 12 ft. long and 18 ins. wide. Glue the seam to the other sides of one stick. Slip the other side frame into the loop, put in the stretchers, adjust the sails smoothly, mark with a pencil, take down and glue. When knocked down this kite folds flat. It cannot be rolled.
The bridle is a loop of twine tied to the sticks at the inner margins of the cambric. Carefully find the exact center of the bridle loop and tie a loop knot there. This settles for all time the point of attachment of the flying string. This kite flies higher than the Malay kite, when bridled as described. By moving the bridle back carefully, a point can be found where the kite will fly low and pull like a mule.
The next type is the square box. It is shown in Fig. 21.
The directions for the Blue Hill box practically cover this, except the bracing. For this case place the hardwood strip vertically, glue and brace as before, with the differences shown. Cut the two holes side by side in the hardwood strip. Glue the spreaders to the side ribs, cut the shoulder on them at the right length, and spring into the holes. Bridle with a single string tied at the point where the inner edge of the cambric of one end crosses one stick. When knocked down this kite will lie flat.
The Malay Box Combination
This kite will add a large spread of sail to the kite described in the foregoing paragraph, by the addition of one stick. Make this stick 8 ft. 4 ins. long. Make it 1 in. wide by ^ in. thick. Notch the ends for the bowstring as described for the Malay. When put together it appears as shown in Fig. 23. This is exactly like two halves of a Malay kite, Fig. 24.
Make the bowstring stick so it can be dismounted, as described for the Malay. This kite is a beautiful flyer, and always attracts much attention when in the air. Three of these this size are all that can be safely handled at one time. This kite will knock down flat by removing the bowstring and bow. This kite, as described above has about 32 ft. of sail.
The Tetrahedral Cell
This kite is the invention of Professor Alexander Graham Bell, and is a scientific wonder. To begin with, a tetrahedron is a solid geometrical figure made by four surfaces, each of which is an equilateral triangle, all of these triangles being of equal size. A tetrahedral cell kite cuts out two of these triangles. The remaining triangles are the flying planes. In its simplest form it looks like Fig. 25. Opened out flat, it appears as shown in Fig. 26.
Now if we fold this on line X and connect points K by a brace exactly as long as one side of the triangle, we have a tetrahedral cell. Tie a bridle to it as shown. This kite has small surface for its weight, but it can be expanded by adding cells until it will carry almost any reasonable weight.
A large and complex tetrahedral is shown at the top of this page. Each cross represents one of the elements shown above, but now the frame work is composed of horizontal bars only. The transverse bars are shown between the rows of cells, and are so marked. The longitudinal bars are shown by the circles. Over this frame when tied together, very fine wires are stretched at the tetrahedral angle, and the cell surfaces are cemented to these.
The surfaces in the kite here shown may be made of very tough Chinese rice paper. With the vertical supports shown, this makes a very light and rigid flying-frame. It is a good plan to start with a few cells and gradually increase the number as you build successive frames and become more expert. The cells can be
arranged in any regular or fantastic
figure as long as they are symmetrical about the keel.
The other 5 sticks should be of the same length, but made of stout bamboo, split about in. wide. Whittle them till they balance nicely when hung inverted from the bottom stick. No other way of fastening can be used except lashing the intersections with fine copper wire or strong cord; braided fish line is good. Make it measure 3 ft. exactly. Every angle in the frame will now be exactly 60 degrees. Divide each stick into 3 equal parts, each one foot long. Take some fine copper wire (No. 28), and stretch it smooth between these division points. When it crosses, tie it with sewing silk or cotton thread lashing. This will make 9 divisions on any face. Set it so you look along the bottom stick, and cover every alternate triangle of wire that shows edge on to the front when you look at it in this position, with strong paper pasted on the wire. Tissue paper is good if strong enough to stand the strain. You should now have ten little paper V’s, 3 on the bottom row, 1 behind ’the other, 4 in the center rows two and two, and 3 on the top, side by side. Looking down on
the kite, it looks like Fig. 28.
Flying this kite will afford much pleasure. It is a most delicate and ethereal object at a great height, looking like a flock of soaring birds more than anything else. It is hard to make, but it pays its way when finally finished in the pleasure it gives its possessor.
A Few Words About Flying
Have a pair of gloves, duck or canvas with pieces of sole leather sewed in, to handle the flying line, if you use wire.
The strain should never come on the reel. A clamp like this, made of castiron with two wingnuts, should be used to clamp on the wire. A short piece of chain with a 3^-in. rod at the end 15 ins. long is attached. The rod is pushed into the ground up to the eye, and the foot is held down on it to prevent its pulling up from the strain. The chain should be as strong as the flying wire. Of course if cord is used for the lower part of the flying wire, it can be handled by snubbing around the frame of the reel, or any convenient stationary object such as a fence post, fire-plug, chimney, etc., when a large battery is aloft.
Smaller kites can be made by reducing the above proportions, and correspondingly lighter equipment can be used, If Malay kites less than 3 ft. high are used they can be covered with paper, although, owing to the imperfect pocket, the headsail action is not so pronounced, and the kite does not fly as steadily as one with cloth sails.
An Emergency Fountain-Pen
SELECT two pen nibs of the round variety and place them together, one above the other, in the penholder. This expedient not only enables one to write about sixty words with one dip in the ink, but prevents the ink from dropping off the pen and blotting the paper.—W. LUHRS.
Making a Two-Fuse Switchblock
TO obviate the annoyance of fitting up a new fuse when one has blown out, a switchblock may be made, which carries two fuses. A block of fiber, Y¿ in. by i Y in. by 3 ins. is used as a base.
Drill two holes 5/16 in. away from each end and Y in. from each side, large enough to take a 4-32 bolt. Drill the same size hole in each end of two thin strips of brass, 1 in. by Y in. Pass one end of each strip over the bolts and bolt the other ends with two nuts, one underneath and one above the strip. Leave the bolts long enough to receive battery post nuts. The end of the block just prepared is used as one binding post, the details being shown in the diagrams. The other ends of the strips are bolted tightly to the base, the bolts being long enough to receive battery post nuts. These bolts are to act as the terminals of the two fuse wires.
Two more holes to take 4-32 bolts are drilled lY ins. from either end and Y in. from either side of the block. After placing the bolts in these holes, a strip of copper or tin is hammered over them and fastened down with brass screws. File down the screws to form a smooth surface. Another hole for a 4-32 bolt is bored 5/16 in. from the end, as shown in the diagram. A piece of brass, I in. by Y in. by Y in-» is bored at each end with a 4-32 drill, and slipped over a bolt of the same bore. A block of fiber, Y in* by Y2 in. by Y2 in., is bored with a 3-32 drill and forced over the bolt. The bolt is then pushed through at the other end.
A nut is placed between the fiber base and the bar to allow for the thickness of the two contact screws and the head of the nut at the other end of the bar. A double set of nuts are used to hold the nut tight. At the top of the bolt is another battery post nut to be used as the other terminal.—L. A. KUEHNE.