440
Molesworth’s pocket-book
WoOT>-WORKING MACHINERY.
Velocity of circular saws at periphery, 6000 to
7000 feet per minute. Rate of feed for circular
saws, 15 to 60 feet per minute. Velocity of the
band-saw, 3500 feet per minute. Velocity of
gang-saws, 20-inch stroke, 120 strokes per minute.
Velocity of scroll-saws, 600 to 800 strokes per
minute. Velocity of planing-machine cutters at
periphery, 4000 to 6000 feet per minute. Travel of
work under planing machine, of an inch foi
each cut. Travel of moulding-machine cutterSj
3500 to 4000 feet per minute. Travel of squaring-*
up-inachine cutters, 7000 to 8000 feet per minute^
Speed of wood-carving drills, 5000 revolutions per
minute. Speed of machine augers, 1| inch dia-
meter, 900 revolutions per minute. Speed of
machine augers, f inch diameter, 1200 revolu-
tions per minute. Gang-saws require for 45 super,
feet of pine per hour, 1 HP indicated. Circular-
saws require for 75 super, feet of pine per hour,
1 HP indicated. In oak or bard wood, ftha of
the above quantity require 1 HP indicated. Main
shafting in wood-working shops, about 300 revo-
lutions per minute. Mortising machines, 250 to
300 strokes per minute; stroke, 6 to 9 inches.
Sharpening Angies of Machine Cutters.
Adziug soft wood across the grain, 30°.
Ordinary soft-wood planing machines, 35°.
Gouges and ploughing machines, 40°.
Hard-wood tool cutters, 50° to 55°.