DESIGN OF APPLIANCES AND METHODS
FOR CASTING ROUND TEST
BARS ON END.
To successfully cast round test bars on end, when the contraction or fluidity is required in connection with the strength and chill of iron, it is essential to utilize a flask, etc., designed especially for such work. Figures 122, 123, and 124, pages 514 to 516, illustrate the design of flask, mould board and patterns with the " whirl-gate " which the author has designed for such a purpose. The test bar patterns and runner are illustrated at H, H, and F, Fig. 128, page 524. These patterns are also seen at D D and A, Fig. 122, page 514. The plan of drawing the patterns out endwise as shown avoids the necessity of any rapping of patterns; hence, if the mould is fairly rammed and the pins of the flasks fit true, it will be evident that few, if any, joints will be seen on the bars obtained.
Moulds cast on end from a parallel pattern will always be largest at the bottom, owing to the head pressure. In making the test bars patterns D D, Fig. 122, for the first standard mentioned in Chapter LXIX., as an illustration, have them 1.1284 inches in diameter, at one end, and 1.0884 at the other. In common i ,