How to Sharpen a Wood Saw
A sharp, well-set saw is essential for fast, easy cutting. You can send a saw away to a toolshop for doctoring, or you can learn to do the job yourself, saving time and money.
Make your first attempt at sharpening on a fairly new saw, because the angles of its teeth will still be easy to see.
You need two triangular files – 150 mm (6 in) for panel and other large saws, and 75 or 100 mm (3 or 4 in) for tenons and dovetails — and a saw set to ensure that the angle at which the teeth are bent out from the blade will be constant.
The sharpening method is much the same for all wood saws. The object is to file the worn teeth to a point by removing as little metal as possible.
First, support the saw in a vice with astrip either side, so it is held firmly throughout its length. Shape the strips with a to fit round the handle. Cramp the blocks in the vice with the teeth just protruding.
Alternatively you can make a saw-sharpening trestle. A trestle holds the saw at a more convenient height for sharpening. Start filing from the handle end on the first tooth bent away from you.
For a, hold the file horizontally and at right angles to the blade. For a cross-cut, panel, tenon or , hold the file in a horizontal position at about 60° to the blade.
Use the original sharpening angle as your guide and stroke the tooth firmly two or three times with the file.
The tooth is sharp when it gleams right up to the point. Move on to the next tooth but one, and then continue along the blade, sharpening every tooth set away from you. Reverse the saw and repeat the process.
Stop filing the instant worn points disappear, otherwise you will skim off too much metal.
The next stage is the setting. Fix the saw higher up in the hardwood blocks before you start.
Adjust the graduated dial on the saw set so that the figure at the top corresponds to the number of teeth in 25 mm (1 in) on the saw. You may prefer to use a higher number, giving a finer setting, if you use the saw mainly for.
Set every alternate tooth, then reverse the saw and set the remaining ones. The saw set is used in the same way as a pair of pliers, fitting over the tooth which is set by a squeeze of the handles.