The Glider Kite
This kite when it is in the air, bears a striking resemblance to a glider. The fact that it is bow shaped in two directions means that a considerable degree of stability can be expected. In the absence of a tail a device is fitted which will help in directional steadiness. The wing, tail, and body, by themselves, do not provide a large sail or cover area, which is helpful in securing buoyancy and lift. To remedy this, an additional cover area is provided in the form of transparent polythene pieces, which assist in the flight of the kite, but do not obscure its distinctive shape. The first stage is to make the framework (Fig. 16). Cut the backbone A, 2 ft. 6 in. in length from stripwood, 3/8 in. square. Make shallow grooves at the ends. Drill two holes at points which are 3/8 in. from each end, and one hole through the sides, which is 3/4 in. from the top end. The backbone is shaped to a slight curve. In order to do this, first soak the wood in water for an hour and assist the shaping by the application of steam heat. The most convenient method is to lay the wood across a pan of hot water. Following this, the backbone may be readily bent into shape. The shape is retained by means of a bowstring threaded through the holes, 3/8 in. from the ends, pulled taut and tied securely. The depth of the curve at the centre is 1 in. Set the backbone on one side for a while for the wood to dry out.
Next, cut the crossbars, B and C, which are 2 ft. 6 in. in length. Use split cane, about 1/4 in. thick. Make shallow grooves in the ends, and also drill holes which are 1/2 in. from each end. These must now be bowed. To do this, whilst the shaping is in progress, subject the cane to dry heat, by holding it over a gas jet or electric fire. This will prevent cracking and splitting and facilitate the shaping. The depth of the curves at the centre is 2 1/2 in. The shape is retained by means of bowstrings as in the case of the backbone. Lay one crossbar on the other to check that the curves are the same, and make sure that the bowstrings are equally taut. Now prepare the tail unit, D and E. D is 1 ft. 61/2 in. in length, and E is 1 ft. 3 in. Use split cane, which is about 1/4 in. thick. Make shallow grooves in the ends, and drill holes in them, 1/2 in. from each end. The bars are bowed in the manner described, using the dry heat method. The depth of the curves at the centre is about 2 in. Lay these bars on the wing crossbars to check that the curves correspond. Join the wing and tail bars together in pairs by means of struts, F. The struts for the wing are 6 in. in length, and those for the tail are 5 in. and all are cut from 1/8 in. X 1/4 in. strip-wood.
The wing connecting struts are fixed 2 in. from the ends of the crossbars; the tail struts are fixed 3 in. from the ends of the crossbar D, and 1 in. from the ends of E. Bind them all securely in place on the underside of the crossbars. Attach the wing and the tail units; the wing at a position where the top crossbar is 2 in. from the end of the backbone; and the tail where its bottom crossbar is 2 in. from the bottom end of the backbone. Glue small stripwood blocks to the backbone on the inside of the wing and the tail frame. Bind round these and the joints with fine string. Smear the binding with thin glue for stiffening. Note that the bow strings lie clear of the backbone on the underside of the framework. Brace the framework with thin strong string. Thread a length through the hole which is 3/4 in. from the top end of the backbone, and bind round and tie, leaving a 5 in. tail to the knot. Pass the string over the end of the backbone, and in turn, over the ends of the crossbars and bottom end of the backbone. Finish by bringing the string again over the top end of the backbone, and tie at the first knot. Secure the string in the grooves by means of cloth strips, glued over the ends of the framework. Secondary bracing strings are added as follows. Tie a length at the bottom left-hand wing joint. Bring it down, loop round and tie at the top left-hand tail joint. Take it to the bottom wing-backbone joint, bind round and tie. From there take the string to the top right-hand tail joint, loop round and tie. Finish by binding round and tying at the bottom right-hand wing joint.
Now tie a length on the bottom left-hand wing crossbar, 3 in. from the backbone. Bring it down to the top tail-backbone joint, loop it round the backbone, and then take it to its tying point on the bottom right-hand wing crossbar, 3 in. from the backbone. See Fig. 16 for details of the bracing. There should be an even tension on all the strings. The wing and tail units should be in the correct horizontal position, and the backbone in the correct vertical position. All the joints must be neat and strongly made. The framework may now be covered. Use pure ribbed kraft (161b.) paper for the wing, body, and tail. Cut a piece first for the body. This is 1 ft. 4 in. in length. The width at the top is 7 in., narrowing to 1/2 in. at the bottom. Glue this to the bottom wing and the top tail crossbars, and over the body bracing strings, which are shaped like a narrow V. The wing cover measures 2 ft. 8 in. in length and 9 in. in width. Glue it to the crossbars and around the end bracing strings. The tail cover is 8 in. in width, and 1 ft. 81/2 in. in length at the top, narrowing to 1 ft. 5 in. at the bottom. Attach it in the same manner as the wing cover.
There may be added to the main covers a supplementary transparent polythene cover which fills in the spaces between the wing, body, and tail. Use very fine polythene and cut two pieces measuring 1 ft. 4 in. in length and 1 ft. 11/2 in. in width. The shape is given at G (Fig. 16). Secure these to the wing and tail, sides of the body and over the outer bracing strings with strips of cellulose adhesive tape, or one of the proprietary brands of adhesive. Add suitable wing and tail markings, cut from coloured gummed paper. The bridle is formed from a 6 ft. length of stout string. It is attached to the backbone in the form of a loop at the points marked X (Fig. 16). The kite line is fastened to the bridle with a bowline knot and a reef knot. See Chapter 7, under 'Knots', for details of these. Next form a loop of string between the bottom tail crossbar and the bottom of the backbone. Tie one end in a bow, so that it can easily be undone. Cut thin washers from cotton reels, which may be threaded on the loop. This device is fitted in place of a tail. One or more of the washers can be suspended by the loop if the kite approaches too near the horizontal in flight. Acting like a weight on a pair of scales, the washers will tilt the nose of the kite upwards. If desired, a windmill may be attached to the top of the backbone. Instructions for making one are given in Chapter 7, under 'Accessories'.