Different Types of Wood Saw

The versatile panel saw

The panel saw is the best buy for a large all-round handsaw; a suitable size is 560 – 600 mm (22-24 in) long with 10 points.

The panel saw’s name is derived from its traditional job of cutting up panels for wardrobe backs, drawer-bottoms and doors, but it cuts large timber generally, both with and across the grain It is rather slow in ripping boards more than 25 mm (1 in) thick. Its teeth are the same as those of a cross-cut saw, but smaller.

Use a panel saw, and other handsaws, with the index finger pointing along the blade for better control. Use the whole length of the blade, applying light pressure on the downward stroke only.

Always make cuts on the waste side of the line you are working to; cutting on the line will leave the wood fractionally undersize, with no scope for planing. Always keep the wood firmly secured — on trestles or similar supports if it is large, in a vice if it is small.

If a large sheet of wood whips when you cut it with a panel saw, rest the sheet on two boards on the trestles and make the cut between the boards.

Plywood and hardboard less than 6 mm (about 1/4 in) thick are best cut with a tenon saw, as a panel saw may tear them.

Choosing and using a tenon saw

The steel or brass-backed tenon saw is probably the most useful all-round saw you can have, and should be the first saw you buy.

It is used for nearly all joint-cutting, with and across the grain — with practice you will be able to cut joints with it so that they fit together without further trimming. Its rigid-backed blade also allows accurate cutting of thin sheet material.

For general use, you should buy a 250 or 300 mm (10 or 12 in) tenon saw with 14-16 points.

Using a tenon saw can be made easier when cutting across the grain by using a bench hook. This is a simple platform which has a strip of wood at one end that butts against the bench and therefore keeps the bench hook still, and another strip on the reverse side at the other end against which wood is gripped with the hand.

You can easily construct a bench hook at home by using a piece of 18 mm (¾ in) hardwood and straight strips which are screwed on. Make the platform about 250 x 175 mm (9 x 7 in).

To make sure you cut a piece of wood squarely, mark lines on the face side and edge and watch both lines as you cut. Saw on the waste side of the lines and plane down to them afterwards to get a clean finish.

In cutting mitres, for example to make picture frames, you should use the tenon (or dovetail) saw with a mitre box. For this the wood is held or cramped in the mitre box and the tenon saw is worked through the diagonal guide slots.

Dovetail saw

The dovetail saw, for practical purposes a smaller version of the tenon saw, is used where a finer cut is needed, as on making dovetails. Unlike the tenon saw, its teeth are not set (splayed out alternately). It relies on the burr produced by filing the teeth sharp to give the blade clearance.

The back on a dovetail saw — as on a tenon saw — is either of brass or steel. The object of this back is to give rigidity and weight. Brass is heavier than steel but more expensive and would probably only be the choice of a professional.

Recommended size if buying a dovetail saw: 200 mm (8 in) with 18-22 points.

Gents saw

The Gents saw is noteworthy as the smallest member of the backsaw family. It has a straight handle and no set on its teeth. It is most useful as a model-making tool, or for cutting joints in both hardwood and softwood on small work. The smallest size is 100 mm (4 in) with a maximum of 32 points. These small saws are usually discarded when blunt but, given good eyesight, you can sharpen the larger ones with a triangular needle-file.

Rip-saw

The rip saw is designed for one specific job — cutting timber fast with the grain It is worth buying if you have a lot of board-ripping to do; if not, use a panel saw.

The rip saw’s teeth, generally four in 25 mm (1 in), are like a series of small chisels. If they cut across the grain they tear out the wood fibres, giving a jagged end. The rip saw works best if the blade is at an angle of about 60° to the wood.

Rip short boards on a single trestle, reversing the wood when the cut gets beyond the half-way mark. Longer work needs two trestles or a couple of chairs Start cutting at one end, continue between the trestles and finish beyond the second support.

Take care when reaching the end of a long cut that the wood does not snap: if necessary, finish the cut from the end opposite the one from which you started, or cramp a piece of wood across the board to stop it juddering.

Cross-cut saw – Cutting across the grain

The cross-cut saw has teeth designed for cutting thick timber across the grain. It leaves a rough finish, however, and is only worth buying if you have a lot of heavy work to do — a panel saw will cope with most cross-cutting quite satisfactorily.

Never saw with the wood between trestles when making a cross-cut, as the wood will bend, jamming the saw, or snap off. Arrange the wood so that the end to be removed overhangs the support. To trim a fraction off the end of a length of wood, cramp a piece of scrap to it, mark lines round both and saw through both pieces at the same time.

Coping saw — for curves and holes

The coping saw is the best all-round saw for curves. It cuts practically any shape, but can saw only as far into the wood as the distance between the blade and the top of the saw frame.

It is versatile enough to tackle jobs ranging from cutting floorboards around pipes to removing waste from dovetails. Cuts can start and finish at the edge of the wood or can be enclosed.

To make an enclosed cut, first drill a hole in the waste part of the wood, thread the blade through the hole and fix it in the frame, then saw to shape.

If you want to cut a grip handle, as shown in the illustration, a better idea is to drill a hole at each end of the waste and saw between them.

The coping saw is available in one size only and has replaceable blades which are discarded when blunt, not resharpened. Blades can be bought singly or, more cheaply, in dozens. If buying a coping saw, specify one for woodwork, otherwise you may get a metalwork coping saw on which the blade angle cannot be adjusted.

Blades are fitted on to retaining pins at each side of the frame. The gap between the retaining pins is greater than the length of the blade. When the blade is fitted the natural spring of the frame tensions it and prevents it bending when in use.

To fit a blade, unscrew the handle, allowing the retaining pin to move forward. Hold the frame steady with one hand while pushing the open ends together between the stomach and a firm object, such as a bench, until the blade pegs can be slipped on the retaining pins. The teeth of the blade must point towards the handle so that cutting is done as the saw is drawn through the work.

Adjust the blade ready for use by tightening up the handle fully and lining up the retaining pins, to ensure the blade is not twisted.

The coping saw can be used with the blade at an angle to the frame, and cutting a curve is often made easier if you adjust the blade to different angles as you proceed.

To adjust the blade angle, turn the handle anti-clockwise, enough to loosen the blade, line up the pins so the blade is at the required angle and not twisted, then retighten the handle before continuing to cut.

The coping saw is sometimes used like a fretsaw (see below). When cutting, always keep your eye on what the blade is doing, not on the ‘unnatural’ angle of the frame.

Padsaw — for work in awkward places

Padsaws cut slowly and are difficult to keep straight, but have the advantage of being able to work where better saws cannot. If you need to cut a hole in the middle of a large panel, for example, the only handsaw that can do the job is a padsaw, working from a drilled hole.

Blades are replaceable and can be bought in a number of lengths. They are clamped in position in the wood or metal handle by tightening a knurled knob or screws. The longer the blade the greater the tendency for it to bend, and although a padsaw blade can be straightened again with the fingers, once it has bent it tends to keep doing so and is therefore best replaced.

Blades can, in theory, be sharpened, but are difficult to hold firmly and it is easier to use a replacement.

Hacksaw blades, for metalworking, can also be fitted into padsaw handles. The commonest use for padsaws is cutting keyholes (hence the alternative name of keyhole saw) and letterboxes.

Keyholes are cut by first drilling a hole, cutting down from it with the padsaw, and clearing out the waste with a chisel. This can be done with a coping saw, but it involves threading and fitting the blade to the frame to make two 6 mm in) cuts.

In cutting a letterbox or similar straight-sided opening, the object is to use the pad-saw as little as possible, because of its limitations.

Finally, start the top and bottom cuts with the padsaw, but as soon as the cuts are long enough, finish off with a panel saw — it is more easily controlled than a padsaw, even when used horizontally.

Bow saw

The bow saw, like the coping saw, cuts curves and special shapes, but its longer, coarser blade allows it to cut faster and to tackle heavier timber. It cannot, however, cut such intricate shapes as the coping saw.

The blade swivels through 360° and its angle is altered by twisting the handle and the knob opposite — do not hold this knob when cutting with the bow saw, it is for adjustment only. Blades are replaceable and are fitted to tapered retaining pins, one at each end of the frame.

To apply tension to the blade, wind the centre wedge round and round until the twine is taut, then slip the wedge down until it is held against the centre crossbar. The teeth of the blade must face away from the handle, to cut on the forward stroke.

If you lose one of the tapered pins which hold the blade in position, a thin panel pin will serve satisfactorily in its place.

Cramp wood which is to be cut with a bow saw as low in the vice as possible, to stop vibration as you work. This may make it necessary to raise the wood several times during the course of cutting, but will make sawing much easier.

Fretsaw

Model-making is the ideal job for the fretsaw, with its ability to cut intricate curves in thin ply. Fit blades with the teeth facing downward, and cut only on the downward stroke. The blade angle is not adjustable as the blades are fine enough to take curves without being turned.

Cut on the line with a fretsaw, as the cut is smooth enough to require no further trimming. Never force the blade so that it bends while cutting.

22. June 2011 by admin
Categories: Hand Tools, Woodworking | Tags: , , , , | Comments Off on Different Types of Wood Saw

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