Читать книгу The Handyman's Book of Tools, Materials, and Processes Employed in Woodworking - Paul N. Hasluck - Страница 18

A carpenter’s try-square that is thought to be untrue may be tested in the following way. Get a piece of board whose edge has been proved to be quite straight, apply the square as shown at A (Fig. 19), and draw a line; then turn the square as at B, and if it is true the blade should fit the line; if it is less than a right angle it will be as shown at C D (Fig. 19), and if more than a right angle the defect will be as indicated at E F (Fig. 19). If the blade has moved or has been knocked out of truth through a fall, it should be knocked back into its proper position, and, when true, the rivets should be tightened by careful hammering. If the blade is too fast in the stock to be knocked back, the blade must be filed true.

Fig. 14.—Mitre Square.

Fig. 15.—Iron Frame Try Square.