Read Ebook: Essentials of woodworking by Griffith Ira Samuel Lawrence Edwin Victor Illustrator

Font size: 10 px 15 px 20 px 25 px 30 px 35 px

Background color: BlackWhiteGrayLight GrayDark GrayDim Gray

Text color: BlackWhiteGrayLight GrayDark GrayDim Gray

Apply/Save settings

Ebook has 374 lines and 38780 words, and 8 pages

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.

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.

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.

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.

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

Before beginning to plane hold the piece toward the light, close one eye and sight as in Fig. 57. If the surface is not warped or in wind, the back arris ab will appear directly behind the front arris cd. Also sight the arrises for straightness, Fig. 58, being careful to hold so as to get the full benefit of the light. Again, test from arris to arris, Fig. 59. The try-square may be used either side up, but the beam must not be held against either edge. It is not for squareness but for straightness that this test is made.

Notice the direction of the grain and place the piece so as not to plane against it. In Fig. 60 plane from A toward B or the surface will be roughened instead of smoothed. When the stock is rough, the direction of the grain cannot be told readily. A few strokes of the plane will give the desired information. As most stock is to be planed to size, it is well to test with the rule before beginning to plane, so as to know just how much margin has been allowed. If you find you cannot true this first surface without getting the piece within one-sixteenth of an inch of the thickness required, ask your instructor to show you where the trouble lies.

These tests ought to give the worker a pretty fair idea of what and how much he dare plane, so that when he begins he may work intelligently. As few shavings as possible, and those thin ones, with the proper result attained, show forethought and care. Nowhere can good, common sense be used to better advantage than in learning to plane.

When planes are not in use they should be laid on their sides, or otherwise placed so that the cutting edge shall not touch anything.

For roughing off and straightening broad surfaces, the jack-plane should be used, and this followed by the smooth-plane.

When using the plane, stand with the right side to the bench; avoid a stooping position. Fig. 61. The plane should rest flat upon the wood from start to finish. Press heavily upon the knob in starting and upon the handle in finishing the stroke. Unless care is taken to hold the plane level in starting and stopping, the result will be as indicated in Fig. 62 A.

Take as long a shaving as the nature of the work will permit. In planing long boards or where it is desired to lower one particular place only, it becomes necessary to stop the stroke before the end of the board is reached. That no mark shall show at the place where the plane-iron is lifted, it is necessary to feather the shaving. This is done by holding the toe of the plane upon the board and raising the heel as the stroke proceeds, beginning just before the stopping point is reached. If the cut is to commence other than at the end of the piece, lower the heel after having started the forward stroke with the toe upon the board.

It is customary to raise the heel of the plane slightly on the backward stroke that the edge may not be dulled.

When the surface has been planed so that it fulfills the tests by sighting described above, an additional test may be given it. Should the board be of any considerable width--three or more inches--the following test will prove sufficient: Place a straight-edge lengthwise, then crosswise the surface planed and along each of its two diagonals. If no light can be seen between the piece and the straight-edge in any of these four tests, the surface may be considered level or true. Fig. 63.

A second test, one which will answer for narrow as well as broad surfaces, differs from the above only in the manner of determining whether the surface is in wind or not. Two sticks, called winding sticks, are prepared by planing their two opposite edges straight and parallel to each other. These sticks are placed across the surface to be tested, close to the ends, and a sight taken over their top edges. If the surface is in wind the edges cannot be made to sight so that one edge will appear directly back of the other, Fig. 64; one end of the back stick will appear high, at the same time the other one will appear low with reference to the edge of the fore stick. The back corner is high only as compared with the fore corner. The wind may be taken out of the surface just as well by planing the fore corner which is diagonally opposite. Usually, equal amounts should be planed from the surface at each of these corners. If, however, the board is thicker at one corner than the other, it is best to take the whole amount at the thicker corner.

That these faces may be known, they are marked with pencil with what are called face marks. There are various ways of making face marks. Unless otherwise instructed, the marks may be made as in Fig. 65; for the face side, a light slanting line about one inch long extending to the edge which is to become the face edge; for the face edge, two light lines across the edge. The marks on both face side and face edge should be placed about the middle of the piece and close together.

These two surfaces are the only ones marked. From one or the other of these, measurements and tests are made. In squaring up stock, for illustration the gage block is held against one or the other of these faces only, and the beam of the try-square when testing for squareness is placed against one or the other of these faces only.

It is the part of wisdom to examine the plane-iron to see that the surface planing has not caused the cutting edge to project unevenly. A plane, set out of true, is likely to cause hours of extra work; it defeats every effort that may be made to hold the plane properly.

Strive to get shavings the full length of the piece, especially on the last few strokes.

The smooth-plane is little if ever used for edge planing on account of its short length. In using the jack-plane in which the edge is slightly rounded, thus making a shaving thicker in the middle than at the edges, avoid tilting the plane to make it cut on one side rather than the other. Move the whole plane over to the high side so that the middle of the cutting edge shall be directly over the high place. Keep the sides of the plane parallel with the edge so as to get the full benefit of the length of the plane.

The caution about planing the first surface, where a definite size is to be attained, applies equally to planing the first edge.

When the edge has been properly trued, put on the face marks suitable for the face edge.

As the line is parallel with the face edge, no straight edge test is necessary. The try-square test for squareness, the beam being held against the face side, must be frequently applied when approaching the gage line.

Where the amount of waste stock to be planed is about an eighth of an inch, the plane-iron may be set a little deeper than average. When near the line, however, it must be set quite shallow. If the waste stock measures more than three sixteenths of an inch, the rip-saw should be used, sawing parallel to the gage line and about one-eighth of an inch away from it.

The test for this side is made by placing the straight-edge across the piece from arris to arris as the planing proceeds, to see that the middle shall be neither high nor low when the gage lines have been reached. No other test is necessary; a little thought will show the reason.

Never attempt to work without lines. If by mistake you plane out your line, take the piece to your instructor at once, unless you have been otherwise directed, that he may tell you what to do.

In free end planing, the cutting edge must not be allowed to reach the farther corner or the corner will be broken off. Plane only part way across the end, stopping the cutting edge half an inch or more from the far edge. Fig. 66. After a few strokes in this direction, reverse the position and plane in the opposite direction, stopping the cutting edge half an inch or more of the first edge.

Keep testing the end as the planing proceeds that you may know what you are doing. Remove no more material than is necessary to square the end, and lay on the rule occasionally that you may not endanger the correct length in your efforts to square this end.

The face edge of the piece should be held against the stop; the wood must not be allowed to project beyond the stop. If it does, the corners, being unsupported, will be broken away as in free planing when the cutting edge is accidentally shoved entirely across the piece.

The bench hook makes an admirable shooting board. Fig. 68.

Hold the plane parallel to the edge in planing with the grain. Swing it to an angle of about forty-five degrees in end chamfering, but move it parallel with the edge, and not with the length of the plane.

The eye will detect inaccuracies in planing. If further test is desired, Fig. 72 illustrates one.

BORING TOOLS--BORING.

The ratchet brace consists of essentially the same parts but in addition has an attachment which permits of the crank's acting in one direction or the other only. It is a necessity where the crank cannot make an entire revolution, and is very convenient for boring in hard wood, or for turning large screws.

To insert a bit, hold the brace firmly with the left hand, revolve the crank until the jaws are opened far enough to allow the bit tang to pass entirely within so that the ends of the jaws shall grip the round part--the shank of the bit. Still firmly holding the brace, revolve the crank in the opposite direction until the bit is firmly held. Fig. 74.

Auger bits are usually supplied in sets of thirteen, in sizes varying from one-fourth of an inch to one inch, by sixteenths.

The size of hole that an auger bit will bore can be told by looking at the number on the tang or shank. If a single number, it is the numerator of a fraction whose denominator is sixteen, the fraction referring to the diameter of the hole which the bit will bore.

Exercise care in laying down a bit; it is easily dulled. Do not use a good auger bit where there is any danger of its striking nails or other metal.

Auger bits are easily sharpened, a small file being used, but they are more easily spoiled by improper filing, and no student should attempt to sharpen one without having personal direction from his instructor.

In boring hard wood or metal, make a "seat" for the point with an awl or, in metal with a center punch. Otherwise it is difficult to start the bit in the exact place.

The gimlet bit, Fig. 78, is used mainly for boring holes for screws.

In using the screwdriver bit, especially in driving screws into hard wood, the bit will tend to jump out of the groove in the head of the screw. To avoid its jumping entirely out and marring the wood, take but half a revolution at a time, then move the brace backward slightly before proceeding again. This allows the bit which has partly worked its way out of the groove to drop back again.

The manner in which a screwdriver bit is sharpened has much to do with its working properly. It should be sharpened like the screwdriver.

The cutting edge of the brad awl should be placed across the grain in starting, and the tool turned half way around and back again, repeating until the proper depth has been bored. It is withdrawn with similar turnings. Fig. 81.

Patent spiral screwdrivers and automatic drills have come into quite common use in recent years. They are used mainly upon light work; their advantage being the rapidity with which they do their work.

To tell whether a bit is boring a hole in the direction which is wanted, it is necessary to sight the bit and brace from two directions at right angles to each other. In horizontal boring, the first sight should be made while in the position shown in the illustration. The second position for sighting would be obtained by inclining the upper part of the body until the eye is on a level with the bit. In vertical boring, Fig. 83, the sighting of the bit would be done across the piece, then along it.

Changing from one position to the other can be done easily and without interfering with the boring and should be done quite often, until the bit has entered well within the wood.

Fig. 84 illustrates a position which is frequently taken when boring in hard wood, or when using the screwdriver bit on large screws. The chin, resting upon the left hand, steadies the tool in the first case, and can be made to give additional pressure in the second.

Where many holes of the same depth are to be bored much time will be saved by cutting a block the length of the exposed part of the bit when the hole is to the required depth. This can be placed beside the bit so that the grip will strike it. Fig. 86.

Share on: WhatsApp @Hash Facebook Tweet