For wooden hand screws, two kinds of screws are required. The back screw, shown in Fig. 1C2, and the shoulder screw having a square shoulder next the handle, as shown in Fig. 183.

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Fig. 182. Back Screw for Wooden Hand Screw.

About the only wood suitable for these screws is straight-grained hickory.

Finish the handle first. Re-set the tee rest and finish the other end the same as in making the vise handle (Figs. 179 and 180).

Fig. 183. Turning Wooden Blank for Screw.

The part on which the thread is to be cut must be smooth and of correct size. By holding the hand, as in Fig. 183, the piece can be smoothed with the skew chisel. Test the piece carefully with the calipers. It should be of the same size as the smooth

Fig. I84. Cutting the Threads for a Wooden Screw.

part of the hole in the screw box, which is to be used in cutting the thread.

Do not use any sandpaper on the part of the piece which is to be threaded. Start the thread by hand, and then place the piece in the lathe. Put the belt on a slow speed. Remove the rest, so that if the screw box becomes stuck, it will not be injured by striking the rest. Move the shifter just enough to cause the piece to revolve slowly (Fig. 184). Some tallow thoroughly rubbed on the wood will cause the screw box to cut a smoother thread.