The adjusting nut and adjusting lever are the controls which vary the depth of cut of the plane iron. The lateral adjusting lever controls the movement of the plane iron from side to side. The smooth plane, jack plane, fore plane, and jointer plane are identical in appearance except for the length of the plane bottom and the manner in which the cutting edge of the blade is ground.
The smooth plane is made in various lengths ranging from 5 1/2" to 10", with blades ranging from 1 1/4" to 2 3/8" wide. As the name implies, the smooth plane is used to smooth the surface of a piece of wood and should be considered as a finishing tool. The blade of a smooth plane is ground straight across.
The jack plane comes in lengths ranging from 11 1/2" to 15", with blade widths of 1 3/4" to 2 3/8". It is a plane intended for heavy, rough work. The, cutting edge of the jack-plane blade is curved as shown, and produces a surface as shown in the same figure.
The fore plane is 18" long, and takes a blade 2 3/8” wide. It is used after the jack plane and before the smooth plane. The cut made by the fore plane is slightly concave compared to the cut of the jack plane. This is due to the fact that the cutting edge of the fore-plane blade is ground to produce an arc A" deep.
The jointer is a plane 22" to 24" long, with a blade 2 3/8” to 2 5/8" wide. It is used as a finishing plane, having the cutting edge of the blade ground straight. Its most common use is dressing and truing the edges of long stock that are to be glued or jointed together. Because of its extremely long bed, it is used to plane a long edge straight.
Adjusting a plane
There are four main adjustment points on a plane with which the woodworker must be familiar. (1) The plane iron and plane iron cap form a single unit which is called a double plane iron. The purpose of the cap is to break and roll the shaving as the plane iron cuts, thereby producing a smooth surface. If the cap is not correctly set in relation to the cutting edge of the blade, it will not function properly. This setting depends on the texture of the wood that is being planed.
(2) The second adjustment controls the pressure applied to the double iron by the lever cap. After the double iron has been assembled, it is placed in the plane. Care must be taken that the cutting edge of the blade does not come in contact with the other metal parts. The projecting end of the Y-lever should set into the slot in the cap and the lateral adjusting lever should be in the slot of the plane iron: The lever cap is then placed over the lever screw, with the cam up.
The lever cap is slipped under the lever screw and the cam pressed down to tighten the double plane iron in place. If, when the cam is pressed down, the double plane iron is not held securely, the cam should be released and the lever-cap screw given a quarter-turn in a clockwise direction. The cam can now be pushed down to apply the pressure. If the cam has to be forced down, the lever-cap screw should be turned in the opposite direction to reduce the pressure. When adjusting the lever-cap screw, no more than an eighth- to a quarter-turn should be made at any time.
(3) The third adjustment controls the depth of cut of the plane blade. This is done with the adjusting nut. As the nut is turned in a clockwise direction, the plane iron is moved in. A reverse motion of the nut will move the plane iron out. When setting a plane iron for depth of cut, hold the plane.
(4) The fourth adjustment controls the lateral setting of the plane iron. To do its work properly a plane must have the blade projecting evenly beyond the bottom. To make the adjustment, hold the plane, with one hand on the lateral adjusting lever. As the lever is pushed to the left, the right-hand corner of the blade is pushed out. When the lever is pushed to the right, the left-hand corner of the blade is moved out. The correct setting should be with both corners of the blade projecting an equal distance beyond the bottom of the plane.
Use of the plane
A concave or hollow edge is usually the result of not keeping the plane parallel to the stock. It may also be caused by using a plane that is too short for the length of stock to be dressed. Long pieces should be dressed with a jointer rather than with a smooth plane. An edge that is not square can be the result of improper adjustment of the lateral lever or of tilting the plane from side to side.
The block plane
The block plane is a low-angle plane; that is, the blade is set so as to meet the wood at a lower angle than the smooth plane. It is made in lengths of 6"and 7", with a blade 1 5/8" wide. The most important use of the block plane is to plane the end grain of the wood. It is used to plane the ends of small pieces of wood and to plane other small areas. The plane is held in one hand only. The instructions and precautions for the use of the smooth plane apply to the block plane also.
It can be enlarged when planing edge grain or when taking relatively deep cuts. Unlike the smooth plane, the block plane has a single iron; when placing the iron in the plane, the bevel of the blade should be up.
When planing the end of a piece of wood with a block plane, the wood is held in the vise and the planing is done from one edge to a little beyond the center; then the work is reversed and the planing is done from the other edge to a little beyond the center. If the plane is worked across the end from edge to edge, the corner is likely to split.
The spoke shave
The spoke shave is a special form of plane with a bottom small enough to follow curves. The blade is adjusted both for depth and lateral position by means of the two adjusting nuts. The thumbscrew on the lever cap, as well as the lever screw, control the pressure of the lever cap on the blade. The blade of a spoke shave is placed in the frame with the bevel side down. The blade should project beyond the bottom of the frame no more than the thickness of a hair. When adjusting the blade you must sight along the bottom in the same manner as for adjusting the blade of a smooth plane.
The combination plane
The combination plane is a special type of plane used to cut grooves and moldings. It is designed to take blades of various shapes and sizes. The blade can be varied for depth of cut by releasing the cutter bolt and turning the cutter adjusting wheel. There is no lateral adjustment on this type of plane.
The plane is equipped with a fence to guide the cutter along an established edge. The depth to which a cut is to be made is controlled by the depth gage. In use, the fence of the combination plane must be kept in close contact with the surface of the wood.
The router is a type of plane which is used to finish the surface of any recess requiring a smooth surface. It consists of a frame or bottom to which are attached knobs by which the tool is held. A cutter is held to the frame by means of a collar. An adjusting screw controls the depth of the blade below the bottom. In use, the blade should be set to cut no more than 1/16" at a time. When finishing a surface with the router, the depth of cut should be considerably less.
The cabinet scraper is a tool used for the final smoothing before sanding. It consists of a frame, a blade, a clamp, and an adjusting screw. The blade is adjusted by loosening the two clamp screws, then setting the scraper on a flat board and pressing the blade lightly against the wood. While pressure is being applied with one hand, the clamp screws are tightened with the other, thereby holding the blade in the same position in the frame.
The blade is bowed or sprung outward to allow the center portion of the blade to project slightly more than the ends of the blade by tightening the adjusting screw. The scraper is then tried, and if necessary the adjustment is changed to produce a thin, even shaving.
A cabinet-scraper blade has its cutting edge ground or filed at an angle of 45 degrees. The cutting edge is turned over with a burnisher to produce a burr. When a blade requires sharpening, the old burr must be removed and a new one formed. To remove the old burr a smooth-cut mill file is used.
The bevel is ground to the correct angle of 45 degrees on a grindstone or with a mill file. The wire edge produced by either of these operations is removed on the oilstone, following the same procedure as outlined for whetting a plane blade except that in this case the bevel angle of 45 degrees must be maintained. The blade is now ready to draw and turn the burr, using a burnisher. Drawing is the operation of stretching the metal to produce a fine wire edge. The edge is drawn with a few firm strokes of the burnisher, held flat on the face side.
The burr is turned by a few firm strokes of the burnisher along the bevel side. The first stroke should be made with the burnisher held at an angle a little greater than 45 degrees, and the angle increased on each succeeding stroke until on the last stroke the burnisher is held at an angle of 75 degrees.
In use, the scraper should be held by the handle and the stock to be worked on held securely by one of the holding tools. The usual procedure is to push the scraper with the blade on the far side of the frame and the adjusting screw facing the operator. It can be pulled toward you provided that the scraper is reversed.
The conditioning of planes
Planes must be kept in condition to do their work properly. With careful handling much uncalled-for grinding and sharpening may be eliminated. In all planes, the cutting edge of the blade projects beyond the bottom of the plane; this means that the cutting edge is exposed at all times. When laying a plane down, place it on its side or with one end on a block of wood to keep the blade from touching the bench top. Planing a surface that has dirt or paint on it or one that has nails driven into it will ruin the cutting edge.
Conditioning a plane iron involves two operations, grinding and whetting. A plane that is dull may not have to be ground to re-sharpen it. The condition of the cutting edge and the angle of the bevel determine whether a plane requires grinding. A blade that is badly nicked from coming in contact with metal must be reground. Slight nicks may be taken out on an oilstone.
Grinding a plane iron
To grind a plane iron, a grindstone or emery wheel with an adjustable tool rest gives the best results. The tool rest is set up at such an angle that when the plane iron is placed flat on it, the blade will come in contact with the face of the grindstone at an angle of 25 to 30 degrees. The blade is placed on the rest with the edge of the blade in contact with the stone. As the grinding is done, the blade is moved back and forth across the face of the stone.
A plane iron having several bevels, through faulty and unsteady grinding, cannot be sharpened satisfactorily on the oilstone. Such poor grinding may be caused by having too small a tool rest or by not replacing the blade properly on the rest after removing it from the stone for inspection.
The end of the plane iron must be square. It should be tested with a trysquare. If the blade is not kept square to the face of the stone, the cutting edge will not be square.
Whetting a plane iron
The actual sharpening of a plane iron is done on an oilstone. The whetting angle should be 30 to 35 degrees. Place the plane iron on the oilstone, bevel side down, with the end opposite the bevel high enough to permit the blade to come in contact with the surface of the stone at an angle of 30 to 35 degrees.
Now turn the blade over and, with the bevel side up, place the flat side on the face of the stone. With both hands on top of the blade, move it back and forth across the stone to remove the wire edge. Complete removal of this wire edge may require repeating these two steps several times.