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Handwork in Wood

Chapter 21: PLANES.
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About This Book

This work provides a practical manual for teaching and practicing woodworking, covering harvesting and sawmilling operations; seasoning, grading, and measuring lumber; selection and use of hand tools and fastenings; shop equipment, layout, and maintenance; construction of common joints and types of wooden structures; fundamental principles of joinery; and methods of surface finishing. Illustrated diagrams and technical descriptions accompany step-by-step procedures and safety and care advice, while a general bibliography and references offer further reading for instructors and craftsmen.



Fig. 66. Paring-Chisel.  Fig. 67. Framing-Chisel.  Fig. 68. Mortise-Chisel.

The paring-chisel, Fig. 66, has a handle specially shaped to give control over its movements, and a long thin blade, which in the best form is beveled on the two edges to facilitate grooving. It is intended only for steady pressure with the hand and not for use with a mallet.

The framing-chisel, Fig. 67, is thick and heavy and was formerly much used in house framing. It is usually made with the handle fitting into a socket on the shank, in order to withstand the shock of heavy blows from the mallet.

The mortise-chisel, Fig. 68, is made abnormally thick to give the stiffness necessary for levering the waste out of mortises.

(2) Chisels are also named according to their shapes: as, skew-chisels, corner-chisels, round-nosed chisels, etc.

The angle of the bevel of a chisel is determined by the kind of wood for which it is most used, hard wood requiring a wider angle than soft wood, in. For order to support the edge ordinary work, the bevel is correctly ground to an angle of about 20°. The chisel is a necessary tool in making almost every kind of joint. It may almost be said that one mark of a good workman is his preference for the chisel. Indeed an excellent motto for the woodworker is: "When in doubt, use a chisel".

In general, there are two uses for the chisel (1), when it is driven by a push with the hand, as in paring, and (2), when it is driven by blows of a mallet, as in digging mortises.

In relation to the grain of the wood, it is used in three directions: (1) longitudinally, that is with the grain, called paring; (2) laterally, across the surface, called cutting sidewise; (3) transversely, that is across the end, called cutting end-wood.



Fig. 69. Paring with a Chisel.

1. Paring. To remove shavings rapidly, the chisel is held flat side up, the handle grasped by the right hand, with the thumb pointing toward the shank, and the blade held in the left hand, as in Fig. 69. Held in this way great control can be exerted and much force applied. For paring the surface as flat and smooth as possible, the chisel should be reversed, that is, held so that the flat side will act as a guide. Held in this way the chisel has no equal for paring except the plane. Paring with the chisel is the method used in cutting stop chamfers. (See p. 185, Chapter VIII.) By holding the cutting edge obliquely to the direction of the grain and of the cut, the effective "sliding cut" is obtained, Fig. 64.



Fig. 70. Chiseling Out a Dado. (First Step).




Fig. 71. Chiseling Out a Dado. (Second Step).
 

2. In sidewise chiseling the chisel is held in the same manner as in paring. A typical form of sidewise chiseling is the cutting out of a dado, Fig. 70. The work may be placed on the bench-hook or held in the vise with the side up from which the groove is to be cut. The chisel is pushed directly across the grain, the blade being somewhat inclined to the upper surface so as to cut off a corner next the saw kerf. After a few cuts thus made with the chisel inclined alternately both ways, the ridge thus formed is taken off, Fig. 71. In this way the surface is lowered to the required depth. If more force be required, the palm of the hand may be used as a mallet.



Fig. 72. Perpendicular Chiseling.

3. In chiseling end-wood, it is well, if possible, to rest the piece to be trimmed flat on the cutting board or on a piece of waste wood. Work done in this way is often called perpendicular chiseling, Fig.72. The handle is grasped in the right hand, thumb up, while the blade of the chisel passes between the thumb and first finger of the left hand, the back of which rests on the work and holds it in place. As the right hand pushes the chisel downwards the thumb and first finger of the left hand control its motion. When chiseling it is well to stand so as to look along the line being cut. Incline the chisel toward you, and use the near part of the cutting edge for a guide and the farther corner for cutting, pushing the handle both down and forward at the same time, Fig. 73. Or, by pushing the chisel sidewise with the thumb of the left hand at the same time that the right hand pushes it downward, the effective sliding cut is obtained.



Fig. 73. Chiseling End Wood.


Fig. 74. Paring a Corner Round.


Fig. 75. Right and Wrong Ways of Perpendicular Chiseling.

End chiseling requires considerable force and therefore only thin shavings should be cut off at a time. Or the mallet may be used with caution. In order to leave a smooth surface the chisel must be very sharp. Even then the lower arris (corner) is likely to be splintered off. This can be prevented by clamping the work down tight with a handscrew to a perfectly smooth cutting board. It is often advisable however, to set the piece upright in the vise and pare off thin shavings horizontally, Fig. 74. In rounding a corner, both this and perpendicular chiseling are common methods. In both cases care should be taken to cut from the side toward the end and not into the grain, lest the piece split, Fig. 75. In horizontal end paring, Fig. 74, in order to prevent splintering, it is well to trim down the arrises diagonally to the line and then to reduce the rest of the end surface.

In all hand chiseling, it is a wise precaution not to try to cut out much material at each stroke but to work back gradually to the line.




Fig. 76. Mallet Chiseling.
The Piece is Clamped Down on the Bench With the Bench Hook.

A typical form of mallet chiseling is the digging of a mortise, Fig. 76. (See also p. 56.) The chisel is held perpendicular in the left hand, while the right hand drives blows with the mallet. The hammer should never be used. (See mallet, p. 96.) By rocking the chisel and at the same time giving it a twisting motion while the edge is kept on the wood, the edge can be stepped to the exact place desired. Care should be taken to work back to the lines gradually, to cut only part way thru from each side (in the case of a thru mortise-and-tenon), and to keep the cut faces perpendicular to the surfaces.

In sharpening a chisel it is of first importance that the back be kept perfectly flat. The bevel is first ground on the grindstone to an angle of about 20° and great care should be taken to keep the edge straight and at right angles to the sides of the blade.



Fig. 77 Whetting a Plane-Bit.

After grinding it is necessary to whet the chisel and other edged tools. (See also under oilstones, p. 121.) First see that there is plenty of oil on the stone. If an iron box be used, Fig. 77, the oil is obtained simply by turning the stone over, for it rests on a pad of felt which is kept wet with kerosene.

Place the beveled edge flat on the stone, feeling to see if it does lie flat, then tip up the chisel and rub it at an angle slightly more obtuse than that which it was ground, Fig. 78. The more nearly the chisel can be whetted at the angle at which it was ground the better. In rubbing, use as much of the stone as possible, so as to wear it down evenly. The motion may be back and forth or spiral, but in either case it should be steady and not rocking. This whetting turns a light wire edge over on the flat side. In order to remove this wire edge, the back of the chisel, that is, the straight, unbeveled side, is held perfectly flat on the whetstone and rubbed, then it is turned over and the bevel rubbed again on the stone. It is necessary to reverse the chisel in this way a number of times, in order to remove the wire edge, but the chisel should never be tipped so as to put any bevel at all on its flat side. Finally, the edge is touched up (stropped) by being drawn over a piece of leather a few times, first on one side, then on the other, still continuing to hold the chisel so as to keep the bevel perfect.



Fig. 78. Grinding Angle, 20°. Whetting Angle, 25°.

To test the sharpness of a whetted edge, draw the tip of the finger or thumb lightly along it, Fig. 79. If the edge be dull, it will feel smooth: if it be sharp, and if care be taken, it will score the skin a little, not enough to cut thru, but just enough to be felt.



Fig. 79. Testing the Sharpness of a Chisel.

The gouge is a form of chisel, the blade of which is concave, and hence the edge curved. When the bevel is on the outside, the common form, it is called an outside bevel gouge or simply a "gouge," Fig. 80; if the bevel is on the inside, it is called an inside bevel, or inside ground, or scribing-gouge, or paring-gouge, Fig. 81.3

Footnote 3: Another confusing nomenclature (Goss) gives the name "inside gouges" to those with the cutting edge on the inside, and "outside gouges" to those with the cutting edge on the outside.



Fig. 80.
Firmer-Gouge Outside Bevel.
Fig. 81.
 Inside bevel Gouge. 

Carving tools are, properly speaking, all chisels, and are of different shapes for facility in carving.

For ordinary gouging, Fig. 82, the blade is gripped firmly by the left hand with the knuckles up, so that a strong control can be exerted over it. The gouge is manipulated in much the same way as the chisel, and like the chisel it is used longitudinally, laterally, and transversely.



Fig. 82. Gouging.

In working with the grain, by twisting the blade on its axis as it moves forward, delicate paring cuts may be made. This is particularly necessary in working cross-grained wood, and is a good illustration of the advantage of the sliding cut.

In gouging out broad surfaces like trays or saddle seats it will be found of great advantage to work laterally, that is across the surface, especially in even grained woods as sweet gum. The tool is not so likely to slip off and run in as when working with the grain.

The gouge that is commonly used for cutting concave outlines on end grain, is the inside bevel gouge. Like the chisel in cutting convex outlines, it is pushed or driven perpendicularly thru the wood laid flat on a cutting board on the bench, as in perpendicular chiseling, Fig. 72. p. 56.

In sharpening an outside bevel gouge, the main bevel is obtained on the grindstone, care being taken to keep the gouge rocking on its axis, so as to get an even curve. It is then whetted on the flat side of a slipstone, Fig. 83, the bevel already obtained on the grindstone being made slightly more obtuse at the edge. A good method is to rock the gouge on its axis with the left hand, while the slipstone held in the right hand is rubbed back and forth on the edge. Then the concave side is rubbed on the round edge of the slipstone, care being taken to avoid putting a bevel on it. Inside bevel gouges need to be ground on a carborundum or other revolving stone having a round edge. The outfit of the agacite grinder, (Fig. 224, p. 120), contains one of these stones. The whetting, of course, is the reverse of that on the outside bevel gouge.



Fig. 83. Whetting a Gouge.


Fig. 84. Sloyd Knife.

The knife differs from the chisel in two respects, (1) the edge is along the side instead of the end, and (2) it has a two-beveled edge. Knives are sometimes made with one side flat for certain kinds of paring work, but these are uncommon. The two-beveled edge is an advantage to the worker in enabling him to cut into the wood at any angle, but it is a disadvantage in that it is incapable of making flat surfaces. The knife is particularly valuable in woodwork for scoring and for certain emergencies. The sloyd knife, Fig. 84, is a tool likely to be misused in the hands of small children, but when sharp and in strong hands, has many valuable uses. A convenient size has a 2½ inch blade. When grinding and whetting a knife, the fact that both sides are beveled alike should be kept in mind.



Fig. 85. Draw-Knife.

The draw-knife, Fig. 85, is ground like a chisel, with the bevel only on one side, but the edge is along the side like a knife. Instead of being pushed into the wood, like a chisel, it is drawn into it by the handles which project in advance of the cutting edge. The handles are sometimes made to fold over the edge, and thus protect it when not in use. The size is indicated by the length of the cutting edge. It is particularly useful in reducing narrow surfaces and in slicing off large pieces, but it is liable to split rather than cut the wood.


SAWS.



Fig. 86. Hand Saw.

The object of the saw is to cut thru a piece of material along a determined line. Its efficiency depends upon (1) the narrowness of the saw cut or "kerf," and (2) upon the force required to drive it thru the material. The thinner the blade, the less material will be cut out and wasted, and the less force will have to be applied. In order to have the saw as thin as possible, almost all the people of the world, except the Anglo Saxons, have saws that cut when they are pulled toward the worker. The blade is in tension while cutting and in compression only when being returned for a new cut. German carpenters use a saw like our turning-saw. English and Americans have developed the saw on the opposite principle, namely, that it should cut on the pushing stroke. As a matter of fact, the crosscut-saw cuts somewhat on the back stroke. The pushing stroke necessitates a thickening of the blade sufficient to prevent buckling,—a not uncommon occurrence in the bands of a novice, in spite of this thickening. But tho this requires more force, and involves more waste, there are the compensations that the arm can exert more pressure in pushing than in pulling, especially when the worker stands upright or stoops over his work, and the stiffer wide blade acts as a guide to the sawyer. Each method has its advantages. Whatever may be true of hand-saws, in machine-saws the tension method, as illustrated by the gang-saw and the band-saw, is steadily displacing the compression method utilized in the circular-saw. Many kinds of work, however, can be done only on the circular-saw.

In order to diminish the disadvantages of the thrusting stroke, the modern hand-saw, Fig. 86, has been gradually improved as the result of much experience and thought. The outline of the blade is tapered in width from handle to point; it is thicker also at the heel (the handle end) than at the point; its thickness also tapers from the teeth to the back. All these tapers gives stiffness where it is most needed. It is made wide for the sake of giving steadiness in sawing. The fact that it is thinner at the back than along the teeth gives it clearance in passing back and forth in the kerf, but the friction is still great, especially in sawing soft or damp wood. To avoid this binding still further, the teeth are "set" alternately one to one side and the next to the other, and so on.



Fig. 87. Rip Saw Teeth: A-edge view, B-side view, C cross-section.
Crosscut-Saw Teeth: A'-edge view, B'-side view, C'-cross-section.

The size of saws is indicated by the length of the blade in inches. The coarseness of the tooth is indicated by the number of "points" to the inch. "Points" should not be confused with teeth as there is always one more point per inch than there are teeth. For example, a five point rip-saw has five points to the inch but only four full teeth, Fig. 87. Rip-saws run from 4 to 7 points per inch; crosscut-saws from 6 to 12 points per inch.

In general, saws are of two kinds, rip-saws and crosscut-saws.

The rip-saw, Fig. 87, may be thought of as a series of chisels set in two parallel rows which overlap each other, for each tooth is filed to a sharp edge which, at each stroke, chisels off a small particle from the end of the wood fibers.

The shape of the teeth is the result of experience in uniting a number of factors: as, strength of the individual tooth, the acuteness of the cutting angle, and the ease of sharpening. The steel of a saw is softer than that of a chisel, in order that it may be filed and set. Hence it is weaker and the edge cannot be so acute. A typical form of tooth is shown in Fig. 87, in which A is an edge view, B the side view, and C a cross section. The angle of each tooth covers 60°, one side, the "face", being at right angles to the line of the teeth. The cutting edge runs at right angles to the sides of the blade.

This arrangement works with entire success along the grain, but if a rip-saw is used to cut across the grain, since there is no provision for cutting thru the fibers, each tooth catches in them and tears them out, thus leaving a rough and jagged surface.

In the crosscut-saw, therefore, the teeth are filed to points, and the cutting edge is on the forward side of each alternate tooth. In Fig. 87. A' is the edge view, B' is the side view and C' is a cross-section. In a properly filed crosscut-saw a needle will slide between these two rows of teeth from one end of the saw to the other.

In action the points, especially their forward edges, cut or score the fibres of wood, and then the triangular elevation of wood left between the two rows of points is crumbled off by friction as the saw passes through. Thus it drops farther and farther into the cut. A crosscut-saw may be thought of as a series of knife points, arranged in two parallel rows. Ordinarily the angle of the "face" of each tooth with the line of the teeth is about 65°, and slightly steeper than the back of the tooth. The angle of the cutting edge of each tooth may be filed more acute when the saw is to be used for soft wood only.

A crosscut-saw when used to rip a board, works slowly, for there is no chisel action to cut out the fibres between the points, but the cut, tho slow, is smooth. In cutting diagonally across a piece of wood, especially soft wood, a rip-saw cuts faster, but a crosscut, smoother. In ripping a board, allowance should always be made for planing to the line afterward. In starting a cut with the rip-saw, the weight of the saw should be borne by the right hand so that the teeth may pass over the edge of the wood as lightly as possible. The left thumb acts as a guide. If the saw be handled thus, and the angle with the board be quite acute, it is not necessary to start with a back stroke. When the kerf is well started, the whole weight of the saw may be applied. An easy light stroke is better than a furious one. The line should be followed carefully, but if the saw runs from the line it may be brought back by taking short strokes near the point of the saw and twisting the blade slightly in the desired direction. If the saw binds and buckles because of the springing together of the wood, the kerf may be wedged open with a screwdriver or a bit of waste wood. A drop of oil rubbed across each side of the saw will make it work more easily.

Care should be taken in finishing a cut to hold up firmly the part of the wood which is being sawn off so that it will not split off or splinter.



Fig. 88. Rip-Sawing on a Horse.

Sawing may be done either on a saw-horse, Fig. 88, or at a bench. For big, rough work, the former is the common way, the worker holding the material in place with one knee, because this method enables him to exert his greatest strength. A convenient way for rip-sawing a small piece of wood is to insert it in the vise, Fig. 89, with the broad side of the board parallel to the vise screw, and the board inclined away from the worker who stands upright. The start is easy, the sawdust does not cover the line, and the board is not in danger of splitting. The board, however, has to be reversed after it is sawn part way thru, in order to finish the saw cut.



Fig. 89. Rip-sawing with Wood Held in Bench-Vise.

The back-saw or tenon-saw, Fig. 90. is a fine crosscut-saw, with a rib of steel along the back, which gives to it its name. Since it is intended for small accurate work, the teeth have little or no set.



Fig. 90. Using the Back-Saw with Bench-Hook.

In sawing, the wood may be held either in the vise or on the bench-hook. To help start the saw and at the same time to keep the edges of the cut sharp, it is well to make a little groove with the knife, on the waste side of the line to be followed, cutting the side of the groove next to the line at right angles to the surface. The saw drops directly into this groove, Fig. 91. In starting the saw cut, the saw should be guided by holding the thumb of the left hand against the side of the saw just above the teeth. Until the kerf is well started, the saw should be held so that the teeth just touch the wood. It is better not to attempt to start the saw level, i. e., with the teeth resting clear across the wood, but the handle should be raised so that the start is made only at the farther edge of the wood. Then as the saw is gradually lowered, the kerf will extend quite across the wood, Fig. 92. When the back-saw is used for ripping, the wood is held in the vise, end up. Begin sawing as in crosscutting, that is, at the farther corner with the handle end of the saw up, and gradually drop the handle. Watch the lines on both the front and back sides, and if necessary, reverse the piece to follow them.



Fig. 91. Starting a Saw Cut in a Trough Cut With Knife.


Fig. 92. Direction of the Back-Saw.
 

The dovetail-saw, Fig. 93, is a small back-saw for delicate work.

The compass-saw, Fig. 94, is narrow, pointed, thick, to prevent buckling, and with a wide set to the teeth, to help in following the curves. The teeth are a cross between the rip and crosscut teeth. It is used in sawing curves.



Fig. 93. Dovetail-saw.


Fig. 94. Compass-Saw.
 

The turning-saw, Fig. 95, is a narrow saw, set in a frame, which stretches the saw tight, so that it works as a tension saw (cf. p. 62). The best frames are made so that the handles which hold the blade can revolve in the frame. The turning-saw is used chiefly for cutting curves. A 14 inch blade, 316 of an inch wide is a good size for ordinary use. The teeth are like those of a rip-saw, so that they are quite likely to tear the wood in cutting across the grain. Allowance should be made for this and the surplus removed with a spokeshave. The turning-saw may be used to cut on either the pulling or the pushing stroke, with the teeth pointed either toward or away from the worker. The pulling cut is generally better, as it puts less strain on the frame than the pushing cut. Both hands should grasp the frame as near the end of the blade as possible, Fig. 95. Turns are made by revolving the frame on the blade as an axis, which should always be kept at right angles to the surface of the board. Care should be taken not to twist the blade.



Fig. 95. Using a Turning Saw.


Fig. 96. Saw-Vise.

To file and set a saw, the saw is first fastened in the saw-vise, Fig. 96, with the teeth up. It is then top-jointed by running a flat file or a saw-jointer, Fig. 97, back and forth lengthwise along the tops of the teeth to bring them to a level. After jointing the saw should be set. For this purpose a saw-set. Fig. 98, is necessary. Every alternate tooth is bent in the direction of its set by the plunger in the instrument pushing against the anvil, which is an adjustable eccentric disc. After the saw is set, it is filed. This is done with a triangular file, Fig. 144, p. 90, which is held in the right hand and its point in the thumb and fingers of the left. Pressure is applied only on the forward stroke, which should be long and even, the file being raised above the tooth on the return stroke. The file should cut in the direction of the set, that is, the teeth having the set away from the worker are filed first. Every alternate tooth, 1st. 3d, 5th, etc., is filed, and then the saw is reversed and the other set, the 2nd, 4th, 6th, etc., is filed.



Fig. 97. A Saw-Jointer.


Fig. 98. Saw-Set.

In filing a rip-saw the file should move exactly perpendicularly to the plane of the saw blade, that is, directly across the teeth. The filing is done on the back of the teeth, the file just touching the face of the next one. The filing is continued, with one, two, or three strokes, for each tooth, as the case may require, or just until each tooth is sharp.

In filing a crosscut-saw, the file is held pointing upward and toward the point of the saw. The file should cut in the direction of the set. The angle of the cutting edge is determined by the horizontal inclination of the file to the blade; the angle of the point is determined by the perpendicular inclination of the file to the blade. Finally the sides of the teeth are rubbed lightly with a slipstone to remove the wire edge. It should always be remembered that a saw is an edge tool, and its edges are as liable to injury as any edges.

PLANES.

The plane is a modified chisel. The chief difference in action between a chisel and a plane in paring is this: the back of the chisel lies close down on the surface of the wood that is cut, and acts as a guide; whereas, in the plane, the cutter is elevated at an angle away from the surface of the wood, and only its cutting edge touches the wood, and it is held and guided mechanically by the plane mechanism. In other words, a plane is a chisel firmly held in a device which raises the cutter at an angle from the work, regulates the depth of the cut, and favors the cutting rather than the splitting action. An illustration of a chisel converted into a plane is the adjustable chisel-gage, Fig. 99.



Fig. 99. Adjustable Chisel-Gage.           Fig. 100. Wooden Bench-Plane.

The plane has developed as follows: it was first a chisel held in a block of wood. This is all that oriental planes are now, simply a sharpened wedge driven into a block of wood. When the hole works too loose, the Japanese carpenter inserts a piece of paper to tighten it, or he makes a new block. The first improvement was the addition of a wooden wedge to hold in place the "plane-iron", as the cutter was formerly called. In this form, the cutter or plane-iron, tho still wedge-shaped, was reversed, being made heavier at the cutting edge in order to facilitate fastening it in the wooden plane-stock by means of the wooden wedge. Then a handle was added for convenience. Then came the cap, the object of which is to break back the shaving and thus weaken it as soon as possible after it is cut. Until a few years ago, this was all that there was in a plane, and such planes are still common, Fig. 100. Finally there appeared the iron plane, Fig. 101, with it various mechanical adjustments. The following are the parts of the Bailey iron plane:4

Footnote 4: The numbers and names in italics are those given in Stanley's Catalog, No. 34. Some of these names, as "plane-iron," are survivals from the days of the wooden plane and are obviously unsuitable now.



Fig. 101 Section of Jack Plane.

  1. Cutter, or bit, or blade, or plane-iron.

  2. Cap, or plane-iron cap, or curling iron.

  3. Cutter screw, or plane-iron Screw.

  4. Clamp, or lever cap, or wedge.

  5. Clamp screw, or cap screw.

  6. Frog.

  7. Y Adjustment.

  8. Brass set screw, or brass adjusting nut.

  9. Lever (for lateral adjustment).

10. Frog screw.

11. Handle.

12. Knob.

13. Handle bolt and nut.

14. Knob screw, or Knob bolt and nut.

15. Handle screw.

16. Bottom, or sole.

17. Toe.

18. Heel.

19. Throat.

20. Thumb piece, or clamp lever, or cam.

There are various principles involved in the action of the plane. The effect of the flat sole is to regulate the cut of the cutter. If the surface be uneven, the cutter will not cut at all, or but little, in passing over low places, since the toe and heel of the sole will then be resting on higher places; but when the cutter reaches a high place a shaving will be taken off. Hence it follows that the longer the plane, the straighter will be the surface produced. The length of the plane used is determined by the length of the wood to be planed, and the degree of straightness desired.

The part of the sole directly in front of the cutter presses firmly down on the wood and so prevents the shaving from splitting far in advance of the edge. It follows that the narrowness of the mouth in a plane is an important factor in the production of smooth surfaces. This can be regulated by adjusting the toe in the block-plane, and by moving the frog in the jack- and smooth-planes.

A recent improvement in jack-, smooth-, and fore-planes consists of an adjustable frog, by means of which the throat can be narrowed or widened at will by means of a set-screw in the rear of the frog without removing the clamp and cutter. It is made by Sargent and Company. The Stanley "Bed Rock" plane has a similar but less convenient device.

The splitting of the wood in advance of the edge is also prevented by the breaking of the shaving as it hits against the cutter or its cap. Hence the advantage of bending up and breaking or partly breaking the shaving as soon as possible after it is cut. This shows why the cap is set close to the edge of the cutter. Another reason is that it thereby stiffens the cutter and prevents "chattering." If a thick shaving be desired the cap has to be set farther back. In a smooth-plane 132 inch is enough, in a jack-plane ⅛ inch is often desirable. The following are the planes in common use:

The jack-plane, Fig. 102, 14" to 15" long, is the one used where a considerable amount of material is to be taken off to bring a piece of wood to size, and therefore the outline of the cutting edge instead of being straight is slightly curved or "crowned" so that in planing the surface of a board it makes a series of shallow grooves, the ridges of which must afterward be smoothed off by another plane. Also for beginners whose hands are not strong it is sometimes wise to grind the cutter with some "crown", in order to take off narrow shavings, which require less strength. For school use, where the jack-plane is used for all purposes, the cutter is usually ground almost straight and only the corners rounded as in the smooth-plane and the fore-plane.5

Footnote 5: In whetting a plane-bit, a slight crown may be given it by rubbing a bit harder at the ends of the edge than in the middle. Strop in the same way as a chisel (p. 59).



Fig. 102. Sighting Along the Sole of Jack-Plane.

The fore-plane, 22" to 26" long, and the jointer, 28" to 30" long, are large planes, similar to the jack-plane, except that the cutting edge is straight. They are used for straightening and smoothing long pieces.

The smooth-plane, 5½" to 10" long, is a short plane, similar to the jack-plane, except that the cutting edge is straight. It is used for smoothing.

These four planes, the jack-plane, the fore-plane, the jointer, and the smooth-plane, are essentially alike, and directions for the use of one apply to all.

There are two chief adjustments in the Bailey iron plane: the brass set-screw, see 8 in Fig. 101, which regulates the depth of the cut, and the lever, 9, which moves the cutter sidewise so that it may be made to cut evenly. The skilful worker keeps constant watch of these adjustments. It is well to form the habit of always sighting along the sole before beginning to plane, in order to see that the cutter projects properly, Fig. 102. It is a common mistake among beginners to let the cutter project too far.

It is important to know what is the best order of procedure in planing up a board. There are often reasons for omitting the planing up of one or more surfaces, but it is wise to form the habit of following a regular order, and the following is suggested as a good one:

1. Working face. Plane one broad side flat and smooth. Finish with the plane set to cut line shavings. Test with try-square. Mark this face with a distinct pencil mark, A, Fig. 103.

2. Working edge. Plane one narrow side straight and square with the working face. Test with try-square, pressing the block of the try-square against the working face. Mark the working edge with two distinct pencil marks, B, Fig. 103.

3. End. First mark the width on the working face with the marking-gage, C, 1-2, Fig. 103. Chisel off the corner, a, of the piece outside this gaged line. True and smooth this end with the plane, making it square with both working face and working edge, D, 2, 3, 4, Fig. 103.

4. Length. Measure the length from the finished end, D, 2-3-4, score across the working face, D, 5-6, and working edge, D, 6-7, using a sharp knife point and the try-square. Saw just outside this line, D, 5-6-7, with the back-saw, cut off the narrow corner, D, b, beyond the gaged line and plane true, E, Fig. 103.

5. Width. Plane to the center of the gaged line, E, 1-2. Test this edge from the working face, F, Fig. 103.

6. Thickness. Mark the thickness with the marking-gage all around the piece, F, 8-9-10. Plane to the center of the gaged line, G, Fig. 103. Test this face for flatness.



Fig. 103. The Order of Planing a Board.

In a word, the order to be followed is graphically represented in H, Fig. 103. The surfaces are numbered consecutively in the order in which they are to be planed.

The advantages of this order are these: by planing the working face first, a broad surface is secured to which the others may be made true. By planing the ends before the width is planed, the danger of splitting off fragments can be avoided by chiseling the corner of the unfinished edges, C, a, and D, b, Fig. 103, into a buttress. By planing the ends and the width before the thickness is planed, a dressed face is secured all around for gaging the thickness. In following this order all measurements and markings are made on a dressed face.

If there be any "wind" or twist in the board, this should be discovered first of all. This may be done roughly by sighting across the broad side of the board, Fig. 104, and more accurately by the use of "winding sticks," see Fig. 205, p. 113. Or the surface may be tested with the plane itself by tilting the plane on its long corner edge, and resting it on the board, while the worker looks between the board and the plane toward the light. It is evident that the plane must be turned in various directions to test for wind, and that a board only as long or as wide as the plane is long can be tested in this way. The try-square or any straight edge may be used for the same purpose, Fig. 105. If there be any wind in the board, this should at once be taken out of one face by planing down the high corners.



Fig. 104. Sighting for Wind.


Fig. 105. Testing from Edge to Edge.

In starting to plane, the worker should bear down on the knob at the front end of the plane. When the plane is well on the board, he should bear down equally on both knob and handle, and as the plane begins to pass off the board he should put all the pressure on the handle end, Fig. 106. By taking pains thus, a convex surface will be avoided, the making of which is a common error of beginners. On the return stroke, the plane should be lifted or tilted so that the cutting edge will not be dulled by rubbing on the wood. This is especially important on rough and dirty boards, as it saves the cutting edge, and in fine work, as it saves the work. If the plane tear the wood instead of cutting it smooth, as it should, it is because the planing is "against the grain". This can often be avoided by noticing the direction of the grain before beginning to plane. But even if it be not noted beforehand, a stroke or two will show the roughness. In such a case, it is necessary simply to turn the wood around.



Fig. 106. Planing an Edge.

The accuracy of the work as it progresses should frequently be tested, and the eye should constantly be trained so that it can more and more be depended upon to detect inaccuracy, Fig. 107. As each surface is trued, it should be carefully smoothed with the cutter set to cut fine shavings.



Fig. 107. Sighting an Edge.

In planing a very cross-grained piece of wood, there are several methods to use for securing a smooth surface. The frog of the plane should be moved forward so that the throat in the front of the cutter is a mere slit. In the ordinary plane it is necessary to remove the cutter in order to reset the frog, but in the Sargent plane and the Stanley "bed rock" plane, it can be set by a set-screw at the rear of the frog. Next, the cap should be set so that the cutter projects but very little beyond it, or, in technical language, the cutter should be set "fine." A sliding cut, see p. 53, should be taken with the plane, and sometimes it may be necessary to move the plane nearly at right angles to the general direction of the grain. By these means even refractory pieces of wood can be well smoothed. See also scrapers, p. 91.

The choking of a plane is the stoppage of the throat by shavings. It may be due simply to the fact that the cutter is dull or that it projects too far below the sole of the plane. In a wooden plane choking is sometimes due to the crowding of shavings under some part of the wedge. When the adjustable frog in a modern plane is improperly placed choking may result. The frog should be far enough forward so that the cutter rests squarely upon it.

Choking may, and most commonly does, take place because the cap does not fit down tight on the cutter. This happens if the cap be nicked or uneven. In consequence, minute shavings are driven between these two irons and choking soon results. The remedy is to sharpen the cap, so that its edge makes a close fit with the cutter. The fit may be made still tighter by rubbing with a screwdriver the edge of the cap down on the cutter after it is screwed in place.

In no tool is it more important to keep the cutter sharp than in the plane. To remove the cutter, in order to sharpen it, first loosen the clamp lever and remove the clamp. Carefully remove the cap and cutter taking pains not to let the edge hit any part of the plane, then using the clamp as a screwdriver, loosen the cap-screw and slide the cap back along the slot in the cutter, where it can be held fast by a turn of the cap-screw. The edge is now free and can readily be whetted. When the cap needs to be entirely removed, for instance, for grinding, after it has been slid along the cutter slot, as before, it is turned at right angles to the cutter, and then slid down the slot until the cap-screw unbuttons from the cutter. The object in sliding the cap up the slot before turning it, is to prevent the danger of injuring the edge. Some caps are now made with the buttonhole at the upper end of the slot.

After sharpening, (see under sharpening, p. 117.) the order is reversed for replacing the cutter. The cap is set at right angles to the cutter, the cap-screw dropped into the slot, the cap is slid up the slot, and turned into line with the cutter, and then slid down the slot till the edge of the cap comes quite near the edge of the cutter. Then the two are held firmly together with the left hand until the cap screw is turned tight.

In replacing the cutter and cap in the plane, care should be taken not to injure the edge and to see that the Y adjustment lever fits into the little slot in the cap; then finally the lever is thrown down tight. Then, by turning the plane sole upward and glancing down it, the proper adjustments with the brass set-screw and lateral adjustment lever are made. When the plane is not being used, it should rest either on a pillow (a little strip of wood in the bench trough), or on its side. In no case should it be dropped sole down flat on the bench.

The block-plane, Fig. 108, gets its name from the fact that it was first made for planing off the ends of clap-boards, a process called "blocking in".