Fig. 7.—Eyebolt.
If the interior of the mould is coated with lamp-black, the castings will require no other finishing than boring the holes.
Two dozen of these sockets are required. Six are fastened to each of the four horizontal members by means of round headed wood screws which pass through the smaller holes in the base. The sockets are located exactly opposite the ends of each strut so that when the stanchions are in place, they will be separated by the same distances but all lie in a plane at right angles to that in which the struts are.
A 1/4 inch hole is bored through the horizontal beam directly under each one of the 1/4 inch holes in the base of the socket. These holes permit an eyebolt to pass through. The eye bolt is illustrated in Fig. 7. The stock is 1/4 inch in diameter and should be at least two inches long under the eye.
Fig. 8.—Assembly of stanchion, socket beam, strut and clamp.
The diameter of the eye is one half an inch. These eye bolts are obtainable already threaded and ready for use with a nut and washers, but can be procured somewhat cheaper in blank form and threaded by the purchaser. Four dozen are necessary, two for each socket. The eye bolts pass through the socket and beam, coming out on the under side directly opposite the holes in the strut clamp. A nut placed on the under side as in Fig. 8 will then hold the clamp tightly against the under side of the beam and secure the position of the strut.
Ribs. Forty one ribs support the cloth forming the surfaces. They are each one half an inch square in cross section and four feet long.
