"The speed of sawing, or the cost of sawing, which is much the same thing as the movement of the teeth, is with the band-saw almost unlimited. Its performance, contrasted with jig-saws for cutting plain sweeps or scroll-work, shows a gain of time or cost of 3 to 1, with the important advantage of being easier to operate, and much more popular with workmen. The greatest objection to a band-saw is that it cannot be used for cutting inside work. Some workmen saw clean through the stuff to get at the inside, when the nature of the work will admit of such treatment without weakening or injuring the design. Strips of the same kind of wood as the design are firmly glued into the saw-kerfs when the work is completed. Of course, this method of reaching inside cutting can only be adopted where the design is not intended to bear any strain. Many devices have been suggested for separating and joining band-saws, but most of them are unavailable or impracticable. One, however, enables the operator to separate the saw, pass it through a hole bored in the wood and join it again, in less time than it takes to disconnect the blade of a jig-saw, pass it through the wood and connect it again to the machinery.

This arrangement gives the band-saw an important advantage over the jig-saw in its own special province, as it renders it possible for much thicker material to be sawn than could be done with the jig-saw, and the work will be better done in less time." (M. Powis Bale, M.I.M.E., A.M.I.C.E.)

(9) "The jig-saw or reciprocating saw is a blade arranged to work upright by means of a crank in a table. One is shown in Fig. 322, p. 226. In setting up a jig-saw, choose the most solid part in the building, over a post, pier, or timber; if on a ground floor, it should be set on solid masonry or piles. If obliged to put the saw on an upper floor, use a counter-balance equal to three-fourths the weight of the movable parts; this will throw the vibration on a horizontal plane. When a jig-saw is set on solid masonry, no counter-balance is required, as it is better to let the vibration fall vertically on the masonry. It is not wise to drive jig-saws a too high a speed, as the wear and tear of the machinery will more than balance the gain in speed of sawing: 300 strokes per minute is about the correct pace. The speed of the feed may be varied according to the nature of the wood being sawn. For very hard wood, a feed of 6 in. per minute is suitable, whilst for very soft wood as much as 30 in. may be cut in the same time; it is a great mistake, however, to force the feed, as the sawdust has not time to escape, and the saws become choked and buckled, and run out of line." (M. Powis Bale, M.I.M.E., A.M.I.C.E.)

(10) A sawing table for using either a jig-saw or a circular saw may conclude this section. An example is shown in Fig. 322. The table consists of 1 1/2-in. planed plank a, about 3 ft. by 2 ft., of beech or good deal, supported on 4 legs 6, 2 or 3 in. square, tied by a framing c to which the plank is screwed. From the centre of the back of the table rises a wooden pillar d, 2 1/2 ft. high and measuring 3 in. by 2, mortised into the table and further held and strengthened by screw-bolts and a T-iron brace, or carried to the floor, or to a longitudinal brace (not shown) joining the 2 back legs near the ground. A strong rubber door-spring f attached to a screwed eye in the arm e pulls the saw g up at each stroke. The lower end of the saw g may be attached directly to the crank of the treadle h, giving only 1 stroke of the saw for each revolution of the fly-wheel i; or, to obtain several strokes for each revolution, the saw is attached by a hook and band to a smaller crank and axle worked by a strap from the fly-wheel, and the saw is at the same time made to work vertically by passing the band over a pulley under the table exactly in line with the upper end of the saw, before taking it to the crank.

For holding down the work whilst sawing, and simultaneously acting as a bearer to keep the saw engaged in its work, a convenient arrangement is to have a block of bard wood k with a slit in the front edge I carried by an iron rod m fitting into the hole n in the arm e, and adjustable by screw-nuts. The fly-wheel may be 18 in. diam. with a heavy rim, and tb.3 main crank 1 1/2-2 in., giving a 3-in. stroke. For working a small circular saw, the wooden poppets op are used, o being tenoned into a square hole in the table, while p is free to slide in a groove. The circular saw and its pulley work in the holes r s respectively in the table.

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Fig. 323 shows a home-made fret-saw, having a capacity ranging from 1/8-in. to 6-in. stuff. The 2 uprights a are of spruce, and measure 7 ft. high and 4 in. sq.; they are mortised at foot into stout planks b screwed down to the workshop floor, and at top into a beam c, 6 ft. long, 4 in. wide, and 3 in. thick. The space between the uprights is 5 ft. 6 in. in the clear. The inner frame d is of pine, 3 in. wide and 2 in. thick, the transverse pieces being composed of 2 lengths of 1-in. stuff, glued and screwed together with the grain reversed. The spring e at the top of the frame is made of 3 pieces of ash, 3/8 in. thick, planed down to 1/8 in. at each extremity; a bolt and nut attaches the spring to the frame, and short lengths of chain or rope connect it with the saw-frame d. The treadle f is hinged to the floor at the lower end, and suspended by straps g from the frame at the upper end. The table h for carrying the work, and through which the saw passes, is supported by 2 strips of batten screwed to the outer frame, and measures 2 ft. long and 18 in. wide. The saw is set up in the usual manner.

Obviously the dimensions may be altered to suit any particular need.

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