Housing. One of the first considerations is usually the housing and storing of the glider, but the machine under consideration is so designed that it may be quickly taken apart or "knocked down" and be put away in the cellar, under the porch or in some other out of the way place.
The framework is composed entirely of selected spruce, straight grained and free from knots. Spruce is very dense and tough but yet one of the lightest of woods.
The dimensions given are for the finished pieces after they have been planed up. The usual method of finishing wood for aeronautical work, so that it has a hard glassy surface and offers little resistance to the air is first to give it a thorough brushing over with hot glue and water. It is rubbed down after drying, using fine sand paper. The wood is then given a coat of thin shellac.
This is rather a tedious operation and instead some may prefer to first smooth up the wood by sand papering and giving it a coat of spar varnish.
The corners of all the woodwork are rounded off so as to reduce the resistance offered to the air.
Horizontal beams. The principal members of the planes when smoothed up should measure 20 feet long, 1 1/2 inches wide and 3/4 inches thick. Four of these beams are required. In some lumber yards, twenty foot spruce free from knots is very hard to secure and so instead, two 10 foot pieces may be spliced together at the centre as shown in Fig. 1.
The splicing strip is 5 feet long and has the same cross section as the beams, save for a distance of one foot from each end where it begins to taper down to 1/4 inch thick. Six holes are bored through the splicing strip and the beams so that they may be fastened together by means of six 3/16 inch round headed stove bolts. The holes are located so that the space between the two centre bolts is six inches while the others are located one foot apart.
A large washer having a small hole in the centre is placed under the head of each bolt as well as the nut.
Fig. 1 Horizontal Beam