A saw will usually be the first tool used to make a cut in the wood for a project, whether you source your wood as rough sawn or planed all round (PAR). To make handling in the workshop easier, it is best to lay out the components you require in chalk on the board(s), and rough cut them slightly oversize. (Don't rush into doing this, as selecting the right areas to cut different components from can affect the end result - more on that elsewhere in the future)
There are many variations of wood saw, primarily weighing speed of cut against quality of finish. The main differentiating factors being:
- Cutting on either the 'push' or the 'pull' stroke
- Serrations, or 'teeth', shaped to best cut with or across the grain
- Density of serrations, or 'teeth per inch' (tpi), also described by the distance between each tooth point, the 'pitch'
- Whether the saw cuts on the push or the pull stroke shouldn't affect the cut
- Saws come in three basic tooth patterns
- optomised for cutting with the grain - known as 'rip' cut
- optomised for cutting across the grain - known as 'cross' cut
- a trade off between the previous two, giving equal performance with and across the grain
- The greater the teeth per inch (the lower the pitch), the smoother the sawn surface and the slower the cut
A few examples
Available in both cross and rip cut, and ranging in blade length from about 20" to 28".
They cut on the push stroke, and have about 8 teeth per inch, which can easily be sharpened.
The thin, flexible blade (or saw plate), has no 'back' to it, and can pass through the wood, up to the handle, making wide cross cuts, and long rips easy.
Length is selected based on the user's physical range of movement while sawing, and the confines in which the saw will be used. The longer the saw, the longer the potential stroke, and therefore the less strokes it takes to cut a certain distance.
Available in both cross and rip cut, and ranging in blade length from about 10" to 16".
Cutting on the push stoke, they have about 10 to 12 teeth per inch, which can easily be sharpened.
The thin saw plate, has a 'back', which stiffens it, making precise straight cuts easy. This makes them ideal for cutting joints.
The weight of the back imparts all the downward force required in a cut.
Normally about 10" in blade length.
With Japanese style tooth pattern, and induction hardened teeth that remain keen for a long time but are difficult to sharpen.
They can equal a tenon saw for straight line precision, and leave a good sawn surface.
Often with swept down handles, which, although comfortable, can restrict use at the bench.
You'll find these in DIY stores and builder's merchants from very little money.
Lengths vary quite a lot, from about 16", and the tpi seems to be ether 8 or 10 across the board.
They work well for both rip and cross cuts, but not as well as dedicated saws.
Hardpoint refers to the induction hardened teeth, which hold their edge well.
These pull saws, which come in either rip, cross, or universal (combination) cut, have thinner blades than western saws meaning that less effort is required to cut with them.
The have no back, so to speak of, relying on the tension created by pulling to keep the blade straight during sawing.
Tooth pattern makes sharpening difficult, but induction hardened teeth last well, and blades are often replaceable.
Small saws ideal for precision work.
Blades about 8" to 10" long, 2" to 3" wide)
Western (top)
Stiff back, and small pitch and set.
14 to 16 tpi is common.
Japanese Dozuki (bottom)
The thinnest bladed Japanese saw.
Fine teeth with little set, and a steel back to strenthen the blade.
Small framed saws with thin and narrow blades.
Ideal for curved work, and cuts where a wide saw plate could not fit.
Cutting on the pull stroke to keep the blade in good tension.
The blade can be rotated through 360° to cut in any direction.
Blades are cheap and easy to replace.
Sawing Technique
Position
Reducing the number of arm joint movements when sawing, seems to increase accuracy and reduce fatigue. To that end, standing with the sawing arm's shoulder in line with the cut really helps. The shoulder movement becomes a straight forward swing motion, the elbow a hinge, and the wrist can remain locked. Together with a well balanced stance, this will work well with most sawing operations.
For more power, you can use your sawing leg (same side as you hold the saw) to push your body in the direction of the cut, assuming you are cutting on the push stroke. For pull saws, you can stand above the work, and use your legs to push your body up and away in the direction of the cut.
Work HoldingWork can be held at the bench with clamps, a vise, or more simply one or two bench hooks.
A bench hook, like the one shown here, can be hooked over the front or back of the bench, and the work held on top, against the fence. Use the front of the bench when cutting on the push stroke, and the rear with pull saws. A second, and possibly even a third hook can be used to support longer lengths.
Hand saws are best used with the work supported lower than the normal workbench, but high enough to allow the full blade length to be used. A dedicated sawyers bench is ideal.
Starting a Saw Cut
In rough work, drawing the length of the saw backwards over the desired starting point, will produce a notch that will adequately hold the blade in place as you make the first cut stroke. This is only suitable for push cut saws. For pull cut saws, either make a notch with a knife or chisel, or draw the blade back lightly whilst resting the saw plate against the tip or knuckle of your thumb.
For fine work, a knife line should have been made to define the cut in advance. By paring from the waste into the base of the knife line, a wedge can be removed, leaving a 'knife wall' agaist which the saw teeth can be held to start the cut.
Finishing a Saw Cut
Ignoring what will happen when you apprach the end of a saw cut, can ruin your efforts. Too much force on the saw, and you will push, rather than cut, through the last part, tearing out material from one or both sides. Not supporting both the waste properly, can cause it's weight to break it off before it is cut through, again tearing out material. Simply reaching over and holding the waste with the non sawing hand, towards the end of the cut, may avoid this. Or you may need to arrange suitable support before you even start sawing.
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