Planes are needed to reduce the thickness of a piece of wood, straighten its edge, smooth its surface, trim joints, work a rebate, or form a groove. Some are of wood and others of metal, but you will not need both. A quite good plan is to have a wood jack plane for the rougher work, and a smoothing and fore plane of metal.
The use and sharpening of planes is similar though they come in for somewhat different purposes. The jack plane is for the rougher sort of work such as removing saw marks, and the quick reduction of thickness, and is normally set fairly coarse. The fore plane, being long, is for truing surfaces and must be set fine. The smoothing plane is used for the final cleaning up of surfaces and again is set fine.
When using either the jack plane or the fore plane on an edge, hold it as in Fig. 10. Notice specially that the fingers of the left hand curl down beneath the sole and touch the surface of the wood. In this way they act as a sort of fence and help to keep the plane in alignment along the edge. When beginning the stroke exert extra pressure with the left hand, and gradually transfer it to the right hand as the far end is reached. This prevents the ends from being dubbed over. If the edge is out of square do not try to rock the plane; push the plane over to the side requiring a thicker shaving as this brings the part of the cutter with the greatest projection into action on the high part. The treatment of end grain is similar except that precautions have to be taken to prevent the grain from splitting out at the far end. One plan when there is sufficient width of wood is to chisel off the corner as in Fig. 11. The alternative, Fig. 12, is used when the wood is not wide enough to permit chiseling.
- Planing an edge. Note that the fingers of the left hand bear against the wood and act as a fence.
- Corner chiseled off. When end grain is being trimmed the far corner is liable to split.
- Block cramped on to stop splitting. Alternative method to
- Here a block is cramped on and its corner chiseled.
In the case of thin wood the plane would be liable to wobble when treating the edge, and the shooting-board is used. The wood lies flat on the thick part of the board, and the plane is worked along the edge. Incidentally, it is invaluable for squaring the ends of timber. The wood is held fast against the stop and, since the latter is at right angles with the edge, the wood is bound to be planed square. For end grain the corner must either be chiseled off first, or a spare piece of wood parallel in its width must be held between the wood and the stop. When planing joints one piece is held face-side uppermost, and the other face-side down wards. This ensures the pieces being in alignment.
This is shown in use in Fig. 14. It should not be used until the surface has been trued up with the fore plane unless the wood has already been machine planed, or is quite short. In common with all metal planes, it needs a lubricant, and for this a wad of cotton wool soaked in linseed oil is excellent. Note how the plane is used at an angle. This gives a slicing cut which is not so liable to tear out the cross-grain. Also, by having a bearing on the adjoining rail, it is more likely to keep flat.
When a plane is new the cutter is ground, but it needs to be sharpened on the oil stone. Remove the wedge by tapping with the hammer the front of the jack plane. In the case of the wood smoothing plane the back is tapped. Metal planes have either a lever cap which is raised, or a screw which is undone. Loosen the bolt which holds the back iron, and pour a few drops of oil on to the stone. Place the cutter on the stone with the bevel lying flat and raise the hands slightly so that just the edge is touching. Work it back and forth as in Fig. 15 until a burr is turned up at the back. This can be detected by drawing the thumb across the edge at the back. Now reverse the cutter flat on the stone and rub it once or twice. This is to loosen the burr. At all costs avoid dubbing over the edge. To remove the burr draw the edge across the corner of a piece of wood, and strop the edge on a piece of thin leather. A keen edge cannot be seen. A dull one shows up as a thin line of light.
A smoothing plane or fore plane cutter should have its edge slightly rounded so that when sighted in the plane the center shows as a thin black line and tapers to nothing at the sides. The jack plane can have the edge rather more rounded because it is invariably set coarser.
- Planing an edge on the shooting-board. The edge of the wood overhangs so that the wood is made straight by the truth of the plane sole. For squaring an end, however, the plane must be kept up to the edge of the upper platform, and the wood held close up to the stop.
- Leveling the joints of a frame using the smoothing plane.
- Sharpening the plane cutter.
Replace the back iron, adjusting it in accordance with the work the plane has to do. Its purpose is to break the shaving as it is raised and so minimize any tendency of the grain to tear out. The closer to the edge it is set the more effective it becomes, but the greater the resistance it offers. It is, therefore, a matter of compromise. For the jack plane it can be set about 12mm. (-Ain.) from the edge; the trying plane when set fine about 1 mm, the smoothing plane bare 1 mm.
How the plane is set. A piece of paper on the bench enables the cutter to be sighted. It should appear as a thin black line, the thickness depending upon the shaving to be re-moved. More detailed information on the care and maintenance of planes is given in the companion volume, Tools for Woodwork.
This small plane is useful for many small jobs. Its small mouth makes it in-valuable for trimming narrow wood which would simply fall into the larger mouth of a bigger plane. Its cutter is fixed with the bevel uppermost.
Those who go in for shaped work will find this an invaluable tool. Its sole can be set to either a convex or concave curve. In use it must always be pushed forward in line with the curve, not used with a slicing action.