Laying Out The Teeth Of A Handsaw

If some of the teeth of a handsaw have been broken off, the saw will have to be ground down to the base of the teeth and new teeth laid out.

A very good way for a beginner to learn the shape of saw teeth and get a clear mental picture of what he is to make in shaping teeth by filing, is for him to lay out a few teeth on an jji ¿A

old blade and file them. If he can lay out and file a few teeth on an old blade, it is reasonable assurance that he can file teeth of a saw. Until he is able to lay out and file teeth on an old blade, he is likely to do more harm than good to a saw when trying to file it.

Procedure for Laying Out Teeth

1. To lay out the teeth for a ripsaw, draw lines at right angles to the cutting edge of the saw, as far apart as the desired points of the teeth. If one is doing it merely to learn how on an old

Ripsaw Tooth Shape Handsaw Gallery

blade, it is suggested that they be spaced % in- apart. (See A, Fig. 49.) A soft pencil may be used on the metal. If the lines do not show up well, the surface may be chalked and the marks made with the point of a divider or some other pointed tool.

2. Set the T bevel at 30 deg. to lay out the backs of the teeth. This is done as shown at B by the use of the steel square and straightedge. The straightedge is placed at 12 in. on the blade and 6 15/16 in. on the tongue of the square.

3. Roughing out of the teeth is done from one side. The work is placed so that the light of a window shines on the lines. The worker should stand with his back to the light if possible. In roughing out the teeth from one side, not all of the metal between the marks is removed; a little over half of it is enough. The saw and clamp are then placed in front of a window or other place where the light shines on the saw and shows up the points of the teeth and every other tooth filed. The saw is then turned and the other teeth filed from the other side.

4. To lay out the teeth of a crosscut handsaw, the spaces are marked off 5, 6, 6%, or whatever number is desired per inch. If teeth are laid out on an old blade as a preliminary task, 14-in. spaces are suggested.

5. The fronts of the teeth are laid out at 78 deg. by use of the T bevel, as directed in drawings D and E.

6. The backs of the teeth are laid out at 42 deg., by use of the T bevel, as directed in drawings F and G.

7. The teeth are roughed out as directed above for ripsaws, and are filed as directed for fitting a crosscut handsaw.

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