Fig. 18 shows the type of plane that is commonly used to smooth and true the broad surfaces, edges, and ends of boards.

Fig. 18.

1A, double plane iron; 1, single plane iron; 2, plane iron cap; 3, cap screw; 4, lever cap; 5, lever cap screw; 6, frog complete; 7, "Y" adjusting lever; 8, adjusting nut; 9, lateral adjusting lever; 10, frog screw; 11, plane handle; 12, plane knob; 13, handle bolt and nut; 14, knob bolt and nut; 15, plane handle screw; 16, plane bottom; 46, frog adjusting screw.

Plane Adjustments

This plane has four principal adjustments:

1. The thickness of shaving taken is regulated by turning the adjusting nut (No. 8, Fig. 18). The direction to turn this nut can only be learned by trial for planes differ in this respect.

The plane is made to take shavings of equal thickness at both edges by means of the lateral adjusting lever (No. 9).

The cap or breaker iron (No. 2) can be moved back from, or down close to, the cutting edge of the plane iron (No. 1) according as one wishes to take thick or thin shavings.

The purpose of this cap iron is to break over the shavings, thus preventing the splitting action that would occur in front of the blade whenever the grain happened to run down into the wood. When the surface is very cross-grained or curly, this splitting action cannot be entirely prevented. It can, however, be reduced to a minimum by moving this breaker iron down to within 1/64" or less of the cutting edge and then taking very thin shavings.

Shape Of Cutting Edge Of Jack Plane Iron.

Fig. 20.

Shape Of Cutting

Edge Of Smooth.

Plane Iron

Fig. 21.

Shape Of Cutting

Edge Of Jointer.

Plane Iron

4. On the best planes the mouth opening may be reduced by moving the frog (No. 6) forward.

This should be done only when the grain is very troublesome and very thin shavings must be taken.

Shape of the Cutting Edge

Figures 19, 20, and 21 show the shapes of the cutting edges of the three principal planes.

In each of the above the iron should be straight, or very nearly so, from X to Y.