Fig. 7. Holdfast and Saw Table.
II. Holdfasts.—Clamps or Cramps, Fig. [7]. These cramps are small iron frames, like three sides of a square, with a screw in the under limb. They are used on the edge of the table to hold the work firmly down to its surface; two or more are always employed. Their fault is that they indent and damage the work; a piece of waste wood may be interposed between the work and the upper limb to prevent this, but such a guard is generally in the way and otherwise objectionable. Hand Screws, Figs. [8] and [9], are a far better tool, entirely free from the above-named objection. They consist of two strips of hard wood rounded at the one end, or jaws, and two screws, also of wood, one of which passes through both jaws, and the other through only one; the end of this second screw entering a recess made in the other jaw to retain it in position. To use them the handles are grasped firmly in the two hands, and the hands are revolved around one another away from you, which causes the jaws to open exactly parallel with one another. When the opening between the jaws equals the thickness of the work and the table, the hand screws are slipped over them, and the second screw then alone receives an extra half turn, this throws the jaws slightly out of parallelism, and effects a powerful grip upon the work at their points. They are exceedingly powerful also in holding work for gluing together and other purposes, and are made of all sizes.
Hand Screws.
Fig. 10.
Carvers’ Screws.