Chapter III: Planes

=18. Planes.=--A standard plane of the present time is shown in Fig. 44. The bottom of this plane is of iron. Fig. 45 shows a plane with the same adjustments in which the bottom is of wood. Planes are made in different sizes. As certain lengths are more suitable for certain kinds of work they have been given distinguishing names such as jack-plane, smooth-plane, fore-plane, jointer. Fig. 44 shows the jack-plane.

The two irons of the plane, the plane-iron or plane-bit, and the cap-iron are fastened together by means of a stout screw. Fig. 46.

This cap-iron serves a double purpose. First: It stiffens the plane iron; second, it serves to bend and break the shaving and thereby prevent a splitting action in front of the cutting edge. This action would surely occur were the grain in the least unfavorable and the cap-iron not used. Fig. 47.

1 Plane-Iron.
2 Cap-Iron.
3 Plane-Iron Screw.
4 Cap.
5 Cap-Screw.
6 Frog.
7 “Y” Adjustment.
8 Adjusting Nut.
9 Lateral Adjustment.
10 Frog Screw.
11 Handle.
12 Knob.
13 Handle “Bolt & Nut”.
14 Knob “Bolt & Nut”.
15 Handle Screw.
16 Bottom.

FIG. 46.]

=19. Setting the Blade.=--The cap-iron should extend to within one-sixteenth of an inch of the cutting edge of the plane-iron in the smooth-plane and three thirty-seconds in the jack-plane. Fig. 48. The screw which holds the plane-iron and cap-iron together must be fastened with a screwdriver--many carpenters use the plane-iron for this purpose--tightly as possible, otherwise a few strokes of the plane and the plane-iron will have been forced up so that the cutting edge will not touch the wood. The reason for this action will be understood when it is seen that the lever of the brass adjusting nut does not act directly on the cap-iron but only on the plane-iron as it is carried along by being fastened with this screw to the cap-iron.

The cap-iron and plane-iron are fastened in the throat of the plane by a cap on one end of which is a little lever or cam.

Should this cam fail to hold the irons firmly, the screw which holds the cap to the frog should be turned with the screwdriver. It should be remembered, however, that this screw, once set, seldom needs adjusting.

Beginners frequently, in ignorance, place the plane-iron and cap-iron together so that the side of the plane-iron having the bevel is next the cap-iron. This results in a loose acting cam and they should look to see that the irons are properly set before changing the screw.

Should it be impossible to force the cam into place without great pressure, first look to see whether the blade rests flat upon the frog before releasing the screw. Frequently the little lever which should enter the small opening in the cap-iron will be found to have entered the opening in the plane-iron only.

=20. Adjustment of the Iron.=--There are two adjustments for the blade of the modern plane. The first consists in turning the thumb-screw or adjusting nut, Fig. 46, that the plane iron may cut a thicker or a thinner shaving. The direction in which it should be turned to give the desired result must be learned by experiment, for in some planes it is the reverse of what it is in others.

A little observation of the action of the screw upon the lever which connects it to the plane iron will show that there is often quite a little lost motion so that it becomes necessary to turn the screw a little before the iron is raised or lowered any. One soon learns by the sense of feeling when the lost motion has been taken up.

The second adjustment is by means of the lever, 9, Fig. 46. Moving this lever to the right or the left serves to straighten the plane-iron, so that the cutting edge shall extend evenly through the mouth and not take a shaving thicker at one side of the iron than at the other.

In adjusting a plane-iron, turn the plane upside down with the toe towards you, hold it toward the light and sight along the bottom, Fig. 49. If the plane-iron projects, observe whether it projects evenly or not. Usually one side will be found to project more than the other. Move the adjusting lever until it shall project uniformly. The cutting edge should project about the thickness of a piece of drawing paper for average work.

=21. The Jack-Plane.=--The jack-plane is about thirteen inches long. Where a full equipment of planes is at hand, the plane-iron of the jack-plane is ground slightly rounding as is shown in Fig. 50 A. The purpose of this plane is to remove rough or large quantities of wood and this shape of blade is best suited for that purpose. Of course the surface of the wood is left in hollows and ridges, and it is necessary to use another plane with a plane-iron ground straight and set shallower in order to smooth the surface.

In manual-training schools where the jack-plane is made to serve the purpose of smooth-plane also, the plane-iron is sharpened straight across and the corners slightly rounded, B, Fig. 50.

=22. The Smooth-Plane.=--The smooth-plane is shorter than the jack-plane. Fig. 51. It is used, as its name implies, for smoothing surfaces. As the straightening is supposed to have been previously done, the shorter length is no disadvantage. For fine work the cap-iron of this plane may be set as close as one thirty-second of an inch to the cutting edge of the plane-iron. The plane-iron should be set correspondingly shallow.

=23. The Jointer.=--This plane is used for straightening long and uneven stock. It is most commonly used for preparing the parts for glue joints. Fig. 52.

Its advantage lies in its length, often two feet or more, which prevents the blade from cutting in the hollow places until all of the high places have been leveled. A short plane would simply follow the irregularities, smoothing but not straightening. The plane-iron of the jointer should be ground straight across.

Fore-planes are short jointers, next in size to the jack-planes, and are used for such work as straightening the edges of doors, windows, etc., when fitting them.

=24. The Block-Plane.=--The block-plane is about six inches long. Fig. 53. It is made especially for cutting across the end of the wood. In addition to the adjusting nut, which is in a different position but serves the same purpose as in the jack-plane, and the lateral adjusting lever, there is a lever for adjusting the size of the opening at the mouth of this plane.

The block-plane differs from the planes just described in that it has no cap-iron, none being needed in end-planing. The plane iron is put in place with the bevel side up instead of down as in the other planes.

The block-plane is not a necessity where a vise can be used for holding the piece to be planed. A smooth-plane or jack-plane may, if the plane-iron be set very shallow, do the work just as well. The block-plane is used mostly by carpenters in fitting together pieces which cannot be taken to the vise. Here the smallness of the plane and the fact that but one hand is needed to operate it are of very great advantage.

=25. The Wooden Plane.=--The old-fashioned wooden planes are still preferred by some woodworkers. The iron bodied planes have displaced them because of the ease with which they can be adjusted rather than because they produce any better results. Wooden planes are subject to warpage and as the bottoms become uneven thru wear, it is necessary to straighten and level them occasionally. The plane-iron and cap-iron of the wooden plane are fastened in the throat of the plane by means of a wooden wedge. This wedge is driven in place with the hammer. Fig. 54 shows the manner of holding the plane while setting the irons and wedge. If the plane-iron does not project enough, the iron is lightly tapped as indicated. If too much projects, the stock is tapped as in Fig. 55. This figure also illustrates the manner of removing the wedge, two or three blows being sufficient to release it so that it can be withdrawn with the hand. In setting the plane-iron, should either corner project more than the other, tap the side of the iron.

Fig. 56 shows the manner of holding the smooth plane in releasing the wedge, as well as when the cutting edge projects too much.

=26. Planing First Surface True.=--A true surface is one which is straight as to its length and width and which has its surface at the four corners in the same plane. Select for this first surface, which we shall call the face side, the better of the two broad surfaces. Knots, sap, wind, shakes, etc., should there be any, must be taken into account when passing judgment. Often the two sides are so nearly alike that there is little reason for choice.

Where several parts are to be fitted together, the faces are turned in; in this case, the best surfaces should not be selected for faces.