And An Emery Grinder

slowly turned backward one revolution. The motor is stopped, and the points of the teeth examined. If not all points have been touched, the bolt through the angle iron is given a turn, thus causing the 1%-in. member to slide on the lower member and the saw forced closer to the grinder. The truing process is thus continued until the shortest tooth is touched. Saws from 8 to 40 in. in diameter may be trued up with the jig. It may also be used to support the saw while gumming it.

Gumming the Saw

Circular saws should be gummed to prevent them from cracking at the rim and to make large, round gullets, which provide ample chambers for holding the sawdust and thus prevent the saws from binding. Gumming a saw consists in grinding or filing out the throat of each tooth to a uniform depth. If an emery grinder is not available, a round file, or a round-back file, which is especially made for this work, should be used to keep the gullets round, smooth, and of the proper depth at each filing. A table should be provided for the saw to rest on while it is being gummed so that it may be fed straight against the grinder. Such a support may be made by using the same rest as is used for the crosscut saw, and an additional piece of 2 by 4 set on edge as in Figure 82, or a rest made to the dimension shown in B, Figure 69,

FIG. 82. GUMMING A COItDWOOD SAW

or by using the circular-saw jointing jig (Fig. 80). It will be noted that this rest (B, Fig. 69) is fitted wTith pegs which fit into the holes near the end of the platform and is much superior to a loose piece, as shown in Figure 82. The hinged table, Figure 79, is shown in use with the bench grinder and stand in Figure 83.

FIG. 83. GUMMING A CIRCULAR SAW, USING THE BENCH GRINDER AND STAND SHOWN IN FIGURE 7 AND THE TABLE SHOWN IN FIGURE 8

If continuous grinding is done at one time at one gullet, the saw blade will become heated, which stretches the rim and will soon make it out of true. The heating also casehardens the steel, making it hard to file. This is overcome by going around the saw several times and by not doing all the grinding in one gullet at one time. The saw should not be crowded against the grinder so as to heat the saw and make it blue. The edge of the emery wheel which is used for grinding out the throats of the teeth should be round, and thick enough to produce large, round gullets.

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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