Saws and their Uses

Saws are important – and often much-abused – items of a household tool equipment. The professional includes in his outfit a rip saw, with large forward-raking teeth for ripping, that is, cutting along the grain; a cross-culling saw, with smaller teeth, set slightly back in front, for cutting across the grain; a panel saiv, with still finer teeth, and a selection of very fine-toothed tenon saws, also called back saws because their thin blades are stiffened by a stout steel or brass bar running along the back or top edge. Panel and tenon saws are intended specially for cross-cutting, the first being specially useful for close cutting in large stuff, and the latter for doing same in small work.

The craftsman will also have provided himself with a dovetail saw, a small edition of the tenon saw, with very fine teoth; compass, pad or keyhole, and bow or frame saws for cutting along curved lines.

For ordinary household purposes, however, one may limit ones purchases to: a 26-inch hand-saw with 5 teeth to the inch, the teeth modified in shape for both ripping and cross-cutting; a 22-inch panel saw, with 9 teeth to the inch; and a 12-inch tenon saw having 12 or 14 teeth to the inch.

If there is a likelihood of much log-sawing having to be done, it is advisable to invest in a saw, single- or double-handed, with teeth specially designed for the purpose. It should be realised that much labour and trouble will be saved if the saw suitable for a particular job is used and not one less suitable: and that muscular effort will be greatly reduced if saws are kept sharp and properly set – opera-ti ms which had better be entrusted to the professional – and free from rust, which increases friction. A little vaseline or other grease applied to a saw before it is used on cutting thick stuff will make it run more easily.

Before cutting up wood that has already been in use, examine it carefully for naiis and screws, which, it need hardly be said, are very destructive of teeth.

A tenon saw should have its teeth protected, when it is not in use, by a shroud made by sinking a cut ¼ inch deep into one edge of a thin strip of wood.

Accessories

There are two things which greatly assist sawing operations. The first is a proper saioing-stool, which any joiner will make for a reasonable sum; and the other is a bench-hook, easily constructed at home, for use when cross-cutting small Btuff on the bench. A hook is quickly made by nailing slats to the ends of a Sawlng-Horse.

SAWS

SAWS a 12-inch x 8-inch piece, on opposite aides. When it is laid on the bench the under slat prevents the hook moving forward as a whole, while the other acts as a stop to the wood being sawn.

Using Saws

It is a good rule to think twice before cutting once. Assuming that a board has been marked down the centre for division into two equal parts, the saw should follow the mark – cut it out – the kerf, or cut made by the saw, lying equally in both parts. But if part only of the board is needed for a special purpose, the cut should be made in the waste part, as guide, and rest the saw lightly on the wood during strokes until a nick has been made. At this stage the saw is held at an angle of about 45° to the work.

For ripping, keep the saw almost vertical after it has entered, so that the face being cut shall be short. A sloping long face means hard work and slow progress. Where thick stuff is being sawn, it pays to keep altering the cutting angle slightly. The head should be held over the saw, so that both sides of it may be visible; and the whole arm moved in a vertical plane.

– Saw nearly upright and cutting on Short face, easily.

– Saw too much sloped, and cutting face too long, making work harder.

A little distance from the line, to allow for planing.

Again, in cross-cutting, it is necessary to cut close up to the lino, so that little if any work on the wood with other tools may be needed. In delicate work the marks for cross-cutting should be mado with the corner of a clnsel; and a sharp sliouldor will be ensured if the chisel cut is made vertically to a depth of & inch or so, and a second cut be made towards it at an angle in the waste, to form a triangular groove. The saw will then have a definite guide.

A saw can be steered more accurately it the first finger be extended along the side of the handle, which is gripped by the other fingers and the thumb.

When starting a cut, use the left thumb The tendency is to swing the elbow sideways, causing the saw to press on the sides of the cut and cause excessive friction. Should the saw stray from the correct line, keep it upright, and during downward strokes give it a twist in the direction needed until it returns to the proper path.

If the saw gets pinched, relieve it by driving a chisel or wedge into the cut some distance from the saw, and moving it forwards as the saw progresses. But when the end of the out is approached the wedge should be removed, lest it should split the wood; and the part not pressed on by the knee should be supported by the left hand till the saw cornea through.

When making a long cut, support the SAWS

Cross-cutting

The work should be marked on the sides as well as the top, except where very thin stuff is in question, and an eye be kept on both the side marks. If this precaution be omitted there is a danger of the cut being slanting on the far side, though it may be vertical on the nearer side.

They may be from 9 to 12 inches long. A saw is set in its frame with its teeth pointing away from the user, so as to cut on the outward strokes.

A hack-saw blade is highly tempered, and snaps easily if it jams; and the teeth break away easily if they catch on thin metal. The work should therefore be held firmly in a vice, and the saw be held at an angle which gives it a long face to bite on.

Before using a hack-saw, make sure that the blade is stretched tight. Do not let the number of strokes per minute exceed .40: too rapid sawing overheats the saw. Be careful to make straight cutting strokes, and to press lightly during the return strokes.

In starting a cross-cut, enter the saw as ior ripping, and then gradually lower its handle end till the cut extends right .across the top. For square or thick stuff the cut may well be carried to a Blight depth dawn both sides, to give the saw A lead. A tenon saw should be used gently, as it easily buckles, and never be employed on work that can be done by a stouter saw. Care is needed in finishing the cut, to avoid tearing the fibres. It is advisable to support the work on a piece of waste wood while the saw is making the last strokes.

Sawing Metal. Saws inch wide and with IS teeth to the inch are recommended.

When cutting a pipe or tube, mark it all round with the saw, and deepen the cut while revolving the part, until the saw IB almost through everywhere, when the cutting may be completed straight through. There will then be no danger of teeth Btraddling metal thick enough to damage them.

A hack-saw and some spare blades should be kept in the house, as the tool will often come in useful. Lead and copper can be cut with an old tenon saw that has become too blunt for its proper work. Wide blades sold for use in an ordinary fretsaw frame are handy for cutting thin metal along curved lines.

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