The figure represents a view of this gauge from the bolt head and needle side of the stem, the thumb-nut being on the opposite side.
This tool finds its field of application upon lathe work, planer work, and, indeed, for one purpose or another upon all machine tools, and in vice work and erecting, examples of its employment being given in connection with all these operations.
Fig. 1459.
[Fig. 1459] represents a scribing block for marking the curves to which to cut the ends of a cylindrical body that joins another, as in the case of a T-pipe. It is much used by pattern-makers. In the figure a is a stem on a stand e. A loose sleeve b slides on a carrying an arm c, holding a pencil at d. A piece of truly surfaced wood or iron w, has marked on it the line j. Two Vs, g, g, receive the work p. Now, if the centres of g, g and of the stand e all coincide with the line j then e will stand central to p, and d may be moved by the hand round p, being allowed to lift and fall so as to conform to the cylindrical surface of p, and a line will be marked showing where to cut away the wood on that side, and all that remains to do is to turn the work over and mark a similar line diametrically opposite, the second line being dotted in at k.
Fig. 1460.
The try square, [Fig. 1460], is composed of a rectangular back f, holding a blade, the edges of the two being at a right angle one to the other and as straight as it is possible to make them. The form shown in the figure is an L-square.