Part 2

Apply the iron to the stone, as indicated by dotted line A, Fig. 33; then raise it until the proper angle is reached, a position indicated by full lines B.

Move the tool gradually from one side of the stone to the other. See that there is plenty of water on the stone. The tool should be held during the operation so that it revolves toward the person grinding. The tool thus held is not so liable to have a “wire edge” as it is if held on the stone while it is revolving away from the operator.

The “whetted” edge should never be ground away unless the plane-iron is in very poor condition.

The grinding is complete when the bevel reaches the cutting edge,—a condition which can readily be determined by holding the finger along the flat side of the iron and having the light fall in the proper direction; a thin bright line will be seen which will determine whether the iron is ground enough. The plane-iron is shown before it is ground in Fig. 34, and Fig. 35 shows it after it is ground.

To whet or sharpen the iron an oil stone is used. Oil stones are of different grades; a stone of medium hardness is best, as it will cut a little faster and leave a fairly smooth edge; whereas if the stone be hard much time is required to whet the iron, but it leaves a smoother edge. A coarse stone leaves a rough edge. Use oil that will not become gummy on the stone. Several good artificial stones have lately come on the market which give good service. To sharpen the iron, apply it as shown in Fig. 36, 1 and 2, and move it back and forth as indicated in Fig. 37.

Many persons sharpen their plane irons as indicated in Fig. 38; at first thought this may appear to be right, but many mechanics of long experience sharpen the “iron” as indicated in Fig. 36. This method gives a stronger edge, which is not so liable to get nicked when the iron strikes a knot or a hard spot in the work.

Great care should be taken to avoid giving the iron a rocking motion on the oil stone, as this will round the edge and the iron will not be any sharper than it would be if it were in the form shown in Fig. 39.

After having whetted the bevel side of the iron sufficiently, turn the iron so that it will rest perfectly flat on the stone, as shown at 3, Fig. 36, and whet it in this position; this will remove the “wire edge.” Care should be taken to see that the iron is not raised in whetting the flat side; if raised as in Fig. 40 the cutting qualities of the edge will be injured.

The iron is now sharpened. Replace the cap iron, keeping it back from ¹/₆₄ to ¹/₃₂ of an inch from the cutting edge; then place it in position and fasten it; look down the face of the plane and see that the edge protrudes far enough to cut the required thickness. The adjustments are made by the thumb screw F and lever K, Fig. 31.

Place the block already sawed on the bench against the bench stop, Fig. 41, and then follow the method here given for planing a piece to the given dimensions.

FIRST.

Plane one side true and mark (0) for the “working face.” (A surface is said to be true when it is perfectly straight across; straight lengthwise, and free from twist).

“Side” here used means one of the wider surfaces in distinction from the narrower surface, the edge.

Methods for testing the surface with parallel strips, etc., will be shown by the instructor.

SECOND.

Plane one edge perfectly straight lengthwise, and square to the face side. Mark this edge for the “working edge”; use the try-square, Fig. 29, to test the work.

THIRD.

Set the gauge, Fig. 42, to the width given in the drawing, and gauge a line from the face edge on both sides; then plane to the gauge lines.

In using the gauge see that it is held as shown in Fig. 43, and push away from the body, having the pressure on the gauge as shown by the line A, B, Fig. 44. This will keep the head of the gauge close to the work. Do not try to mark a line by holding it as in Fig. 45, with the spur at right angles to the work, as it will generally follow the fibre of the wood and a crooked, ragged line will be the result. By holding it as shown in Fig. 43 (and gently letting the spur touch the work, going over it once or twice until the line is of the desired heaviness to work to) a clear, clean-cut line will be obtained.

FOURTH.

Set the gauge to the given thickness (see drawing for dimension) and gauge a line on both edges from face side; then plane to gauge lines. This, if done correctly, will finish the four surfaces. It is sometimes necessary that the ends of a piece of work should be finished smooth; the method of procedure is as follows:

Mark (from one end about ¹/₆₄ of an inch) a knife line all around (see Fig. 46), placing the head of the try-square against the face edge and the face side only; then take a small block and put behind the exercise as shown in Fig. 47, fasten in the vise, and plane to the knife lines. This block will save the corners from breaking.

To finish the other end measure the length and mark as on the first end. Then if the piece is too long to plane, saw off near the line, using the back-saw as shown at Fig. 54, and then finish with the plane to the lines.

In planing care must be taken to see that the plane is held firmly on the work to secure a true surface. A rocking motion must be avoided. In order to get the best results see that the front of the plane is held down with the left hand, also pressing down and forward with the right hand at the same time, and at the end of the stroke lift the front of the plane as shown in Fig. 48; never let it drop as in Fig. 49.

A proper and an improper position to stand while planing is shown by Figs. 50 and 51.

In planing the edge if it is higher on one side than the other, move the plane over to the high side and plane it down. Fig. 52 shows the position of the plane.

After the block is planed true and to the correct dimensions, lay out the lines across the face at the left hand end shown in the drawing and square the lines down the depth on the edges; then set the gauge and mark around the end and notch on both edges. Beginners will find it a little difficult at first to saw a perfectly clean line so as to secure a sharp corner; by cutting notches with a knife point as shown at Fig. 53, it will be easy to secure sharp corners. Place the back-saw, Fig. 54, in the notch, hold it tightly against the flat side, and saw down to the desired depth, removing the portion from the end with the rip saw (see Fig. 55).

To remove the portion between the sawed lines take the chisel, Fig. 56 (the same directions to be used for grinding and sharpening a chisel as are used for the plane-iron), pare lightly (about half through the width of the piece), cut down to the gauge line, and then turn the piece around and finish from the other side, leaving a straight surface at the bottom of the notch. Be careful not to take too heavy a cut, for the chisel will be hard to guide if the workman has to exert his whole strength to push it through the wood. The chisel has a tendency to go down into the work if the flat side is not used as a guiding surface; this side, if kept in contact with the solid wood, will insure a straight surface, and consequently accurate work.

The lining on the exercise is made with the gauge for the lines running parallel with the edge, with the square and the knife for the lines at right angles to the edge, and with the bevel, Fig. 57, and the knife for the oblique lines. Figs. 58 and 59 give methods for finding the angle of 45 degrees, which is the angle that is used for the oblique lines.

Too much attention cannot be given to the operations in this exercise, for in all work that requires material to be prepared, carelessness in detail and inattention to methods, etc., will always appear in the finished work.

EXERCISE NUMBER 2.

HALVED JOINT.

When two pieces of timber of equal thickness cross each other and the joint is to be flush, i. e., the pieces when joined are to form a flat surface, they are halved together; or, to put it in another way, a piece is taken out of each half its thickness and as broad as the piece which is to cross it, thus allowing the one to drop into the other, as shown in Fig. 60. The working drawing is shown in Fig. 61.

To make this piece of work, refer to methods and operations given for the preparation of material in the first exercise.

Special results are sought for by specific methods in this exercise. Exercises that are not finished (by the methods given) as they should be, are thrown out as not coming up to the requirements and fall short of the object for which they are designed.

The drawing shows two pieces of wood of given dimensions crossing each other at right angles and halved together, making a flush joint. _Requirements_: The pieces to be of the exact length, breadth, and thickness called for, fitted closely on both sides, each piece to be exactly in the center of the other, and both sides smoothed off and perfectly flat when finished; the ends of the pieces to be planed square, and the ends of the halving to be fitted from the saw. _Methods_: After sawing out a piece (long enough to make both pieces, allowing for work on the ends), plane the piece by the methods given for planing in the first exercise; then saw it across in the center and proceed to lay out the pieces so that the face side of each piece will come on the same side; this means that the halving is cut out of the face of one piece and the back of the other (see Fig. 60).

It will be well to consider this problem of laying out work as a problem in arithmetic. The pieces called for in the drawing are 5½ inches long, 1½ inches wide, and 1 inch thick. The piece that crosses comes exactly in the center. Therefore we have a problem like this: 5½″ -1½″ = 4″, which is the difference between the length of one piece and the breadth of the other; but the piece comes in the center, and so we take the difference of the length, which is 4″, and divide it by 2. 4″/2 = 2″, which will give the distance from the end up to the first edge of the cross-piece. As all measurements have a beginning somewhere, we mark a line near the end of the piece as shown in Fig. 62, and from this line we lay off the distance to the cross-piece, marking with a knife point the position of the edge. Then we lay off the width of the cross-piece, which is 1½″, leaving the distance to the other end 2″, the same as at the first end.

Having found the position of the edges of the cross-piece, we mark a line across the work (using a knife and a square); then mark the lines down the edges. Now taking the gauge, we gauge from the _face side of each piece_ the depth required. Then we cut a notch _inside the lines_ with a knife, as shown at Fig. 53, place the piece on the bench hook, saw down to the gauge lines with the back-saw (position shown in Fig. 54), and remove the portions to be taken out by the methods given for the notch in the first exercise.

Then plane the ends of each piece perfectly square to the face side and face edge.

An exercise that was made by a careful student and one that was made by a careless student are shown at Fig. 63, revealing the final results of careful as against careless work.

Having cut out the center pieces and finished the ends we fit them together, seeing that the surfaces come flush; then smooth off the surfaces, being careful not to cut too much off the ends, for this will round the surfaces and thus spoil the work. Sharp tools are essential to good work.

Lines drawn in their proper places, and then cut to, will give the results sought for in fitting.

EXERCISE NUMBER 3.

MORTISE AND TENON.

When beams or pieces of wood stand square with each other, and the strains are also square with the pieces and in the plane of the frame, the most common junction is the mortise and tenon.

A mortise is an opening, which may be square or oblong, intended to receive the tenon, and which may go into the work only a short distance, or may go all the way through. Where it goes only part way through it is called a blind mortise, and where it passes all the way through, a through mortise. A tenon is a projection on the end of a piece and fits into the mortise. The tenon usually has two shoulders formed by cutting away the sides, and should be about one third the thickness of the piece.

There are a number of different styles of this joint and methods of fastening, which we will consider later in our work.

The working drawing shown in Fig. 64 gives the dimensions of the pieces, the material of which is to be worked out in one piece, as directed in the previous exercise, and then cut up into lengths suitable for the exercise. The student should commence work on a piece with a full understanding of what is required to be done in order to finish the work as called for, and not try to make any kind of work do in order to proceed to the next task.

Notice what is required in this exercise:

1st. That the pieces be perfectly straight and square.

2nd. That the tenon piece be exactly in the center of the mortise piece, and that the angles be right angles or “square.”

3rd. That the work be laid out systematically, with the lines in their proper places.

4th. That the tenon be made altogether with the saw.

5th. That the mortise be cut out with the hand mortising chisel.

6th. That the tenon fit into the mortise, and not be squeezed.

7th. That the joint fit closely, and that the work be finished off smoothly on the sides, with all the corners sharp and the end of the pieces sawed square.

The following methods if carried out will help the student to finish the work as required.

It will be unnecessary to repeat hereafter the method of planing, as the student by this time should have learned to plane the pieces properly to dimensions.

After the material has been planed, mark the piece to the desired lengths as shown in Fig. 65, and saw off the pieces square on the ends. Use the knife to mark the lines. In sawing, care must be taken to saw on the right side of the line, for the saw will cut out its own thickness and reduce the length of the piece that much if the piece is sawed on the wrong side of the line.

Leave the tenon piece about ⅛ inch longer than the drawing calls for so that the tenon will protrude through and be finished off even with the mortise piece.

Proceed to lay out the work. Take the mortise piece, which is 6 inches long, and mark the distance from one end (6″-1½″ = 4½″.) 4½″/2 = ⁹/₂ × ½ = ⁹/₄ or 2¼″; locate the first point on the face edge; then measure from this point the width of the tenon piece, which is 1½″. Through the points just found draw the lines square to the face side. Place the square against the face edge and mark (on the opposite edge on the corner), a small cut for both lines (see Fig. 66) and square from the face side across the edge; lay the piece aside; take the tenon piece and point off the distance from the end of the piece to the shoulder, and mark across the face and back, using the square and the knife in marking. Prepare the shoulder lines for the back-saw, as shown in Fig. 53, taking care that the notch is cut on the right side of the line.

Take the gauge and set it to the distance from the face side to the first side of the mortise, and gauge the lines for the mortise on both edges; gauge the lines for the tenon. (This is for a single gauge.) Take the mortise chisel, Fig. 67, and make a mark from this line (see Fig. 68), which will give the thickness of the tenon and the width of the mortise; set the gauge out to the width and gauge the rest of the lines.

Take the rip-saw and saw down the outside of the lines on the tenon piece the length required; cut off the sides with the back-saw. In sawing split the line so that the tenon will be as thick as the mortise is wide. This means that half the line is to be left on the work. Fasten the mortise piece in the vise, putting a piece below to keep it from going down when cutting.

Place the mortise chisel about the center of the mortise; hold it vertically, and with the mallet drive the chisel down into the work; release the chisel and make a new cut, keeping the flat side of the chisel towards the end to which the mortise is being cut. Fig. 69 shows how the cutting should be done.

Having reached the end, turn the chisel around, and cut towards the other end in the same manner. (Where the mortise goes through it will be unnecessary to take the chips from the first side.)

Turn the piece over, and repeat the operation on the other side, when the chips can be easily removed. Proceed to test the work; see that the mortise is straight on the ends. Generally the student will leave the ends rounding as shown in Fig. 70; this, if the tenon is driven into the mortise, will squeeze the edges out of true (Fig. 71) and leave an opening on the ends of the mortise, as shown in Fig. 72.

Care should be taken to avoid this fault in this exercise. (A mortise gauge such as a joiner uses is shown in Fig. 73; it has two spurs, one being adjusted by the thumb screw at the end of the shank. We will use a mortise gauge in our work later on.)

After the pieces have been cut, put them together, having the face sides together, and finish smoothly.

EXERCISE NUMBER 4.

KEYED MORTISE AND TENON, WITH BRACE.

This method of joining timbers is sometimes used in heavy frame work, but can be used to advantage in light frame work that has to be taken apart, such as curtain frames, etc.

In Fig. 74 is shown the assembled and the detailed drawings of this piece of work. The experience gained from the previous exercises can be used to advantage in working this problem.

The requirements in this exercise are that all pieces be square and to dimensions.

That the upright and cross-pieces when keyed be square to each other.

That the brace fit snugly, and form two angles of 45 degrees back at its junction with the upright and cross-piece.

That all joints fit closely, and the whole work be smoothed off and made true.

The method of laying out the keyed joint is somewhat similar to that in the third exercise.

On the upright locate the cross-piece (on the face edge), which is 1½ inches from the end to the upper edge, and measure the width of the piece, which is 1½ inches; draw the lines square to the face side, deduct the amount of splay or bevel that is given to the mortise and tenon from the lower end of the mortise, and add to the upper end the width of the key; draw the lines, and mark them in some manner so that they will be known as working lines. Figs. 75 and 76 will show how this may be done.

From the line which locates the lower edge of the cross-piece (using the square on the face edge) mark the position (on the opposite corner) of the lower line on the outside edge, by the method given in the previous exercise (see Fig. 66), and square this line across the outside edge; then measure the width of the tenon, plus the width of the key, and square the line across.

(Where work is to be finished on the faces, care should be taken not to mark the work with knife lines, but if auxiliary lines must be used, then mark them with a pencil so that they may be cleaned off when the work is being smoothed.)

Having laid out the keyed mortise lay out the brace mortise, the lower end of which is located 3½ inches below the lower edge of the cross piece; the drawing gives all the dimensions for this.

Take the cross-piece and lay out the tenon in the same way that the tenon in Exercise Number 3 is prepared, using the dimensions that are given in the drawing for the work on hand.

After marking the shoulders of the cross-piece lay out the brace mortise, which is 3½ inches from the shoulder to the farthest end, and mark the other lines as called for in the drawing. Use the single gauge as directed in Exercise Number 3 to mark the side lines of the mortise and tenon, and cut the mortise with the mortising chisel, taking care to cut the ends to the proper angle.

Saw the tenon as previously directed, and after the sides have been cut off, mark the splay on the lower side of the tenon and cut it off with a paring chisel.

The method of finding the length of the brace is of importance, as it will give the student some idea of the application of square root to practical work of this kind.

The hypotenuse of a right-angled triangle equals the square root of the sum of the squares of its sides. For example, take the triangle that is formed by the upright, the cross-piece, and the outside of the brace. We have a triangle that has two sides of equal length and wish to obtain the length of the brace on its longest side.

We will designate the angle where the cross-piece meets the upright, A, and the lower point of the brace on the upright, B, and the outside point of the brace on the cross-piece, C. Then we have the side AB, and the side AC, which we will square and add together, then extract the square root of this sum, which will give us the length of the brace on the longest side, to which we must add the length of the tenons that go into the upright and the cross-piece. The angles at each end of the brace will be 45 degrees, as the opposite angles of the triangle are equal, there being 180 degrees in the sum of the three angles; one of the angles is a right angle (90 degrees), which we subtract from 180 degrees; the remainder divided by two will give the number of degrees contained in the angle at the ends of the brace.

The lines at the outside of the tenons on the brace are parallel with the upright and the cross-piece respectively.

A method often used by practical men to get the length of short braces is to take a steel framing square and a rule, and find the length of the brace by applying the rule to the square as shown in Fig. 77. On the short leg of the square will be found a brace measure which gives the length of the sides of the triangle and the length of the brace, thus, ⁵⁴″/₅₄″ = 76.31″.

Bevels and tapers are found by applying the bevel to the square according to the bevel or the taper required, such as 1 inch on one side and 4 inches on the other side of the square; this would be called a taper of 1 inch in 4 inches.

Having cut the pieces to dimensions as called for in the drawing, put them together, and finish smooth.

EXERCISE NUMBER 5.

Moldings and beads are sometimes used to ornament work, but the chief use of the bead is to conceal open joints by the shadow it casts. An example of this may be seen in beaded wainscoting or large surfaces that are finished with matched ceiling. If the boards were put together without a beaded edge, an unsightly crack would be the result from the shrinking and swelling of the material.