There are various ways of adjusting iron planes. To make the plane cut a thicker or thinner shaving the milled thumb-screw A (Fig. 169) is turned. The proper way to turn it must be learned by experiment, as it is not turned the same way in different styles of planes. Remember that there is often a considerable lost motion in the screw and lever, so that the screw must be turned a little before it will have any effect in changing the thickness of the shaving.

In your first experiments at setting the plane, turn the screw so that the plane will not cut at all and then turn it in the opposite direction, testing it on a bit of waste material to see when it is cutting properly. Turn the screw but a little at a time, testing it often on the piece of waste and also each time hold it as shown at Fig. 169 or 170, sighting lengthwise of the bottom or sole of the plane. You will soon be able to see how much the cutting edge projects from the surface so that you can set the plane without using the piece of wood for testing it.

Fig 169. Sighting the Bottom of the Iron Plane.

Fig. 170. Sighting the Bottom of the Wooden Plane.

As soon as the plane cuts at all look carefully to see whether it is cutting the shaving at the center or near one edge. If the shaving does not come up at the center of the plane, move the lever B

(Fig. 169) sidewise until it does. If there is no lever for moving the bit sidewise you must strike the side of the bit near the top end with a hammer as in adjusting the wooden plane (Fig. 170).

Fig. 171. Withdrawing the Plane Iron of the Wooden Plane.

Sometimes the bit does not stay in place after being adjusted. This may be caused by carelessness in handling, or the screw (Fig. 173 S) may be loose. This screw should be so adjusted that when the cam lever (Fig. 173) is down the bit will be held firmly in place. The wooden bottom iron planes are adjusted in the same manner as the iron planes. The wooden planes are adjusted entirely with a hammer. To w i t h d r a w the iron, the plane is struck with a hammer on the top near the front end as shown in Fig. 171.

Strike the iron a light blow on the upper end to increase the thickness of the shaving. When the bottom of the wooden plane or the wooden-bottom iron plane becomes worn out of true, draw the iron well out of the way and dress the bottom of the plane, as shown in Fig. 172. This figure shows an iron jointer plane in use, but the work may be well done by using a good iron jack plane.

Fig. 172. Jointing the Bottom of a Wooden Plane.