the bench at the rear, for the various
tools when not in use, and the rear board of the bench should be
elevated above the front planks several inches, on which the various
tools can be put, other than those which are suspended on the rack
above.
The advantage of this is, that a bench will accumulate a quantity of
material that the tools can hide in, and there is nothing more annoying
than to hunt over a lot of trash to get what is needed. It is necessary
to emphasize the necessity of always putting a tool back in its proper
place, immediately after using.
CHAPTER II
HOW TO GRIND AND SHARPEN TOOLS
It is singular, that with the immense variety of tools set forth in the
preceding chapter, how few, really, require the art of the workman to
grind and sharpen. If we take the lathe, the drilling machine, as well
as the shaper, planer, milling machine, and all power-driven tools, they
are merely mechanism contrived to handle some small, and, apparently,
inconsequential tool, which does the work on the material.
IMPORTANCE OF THE CUTTING TOOL.--But it is this very fact that makes the
preparation of that part of the mechanism so important. Here we have a
lathe, weighing a thousand pounds, worth hundreds of dollars,
concentrating its entire energies on a little bit, weighing eight
ounces, and worth less than a dollar. It may thus readily be seen that
it is the little bar of metal from which the small tool is made that
needs our care and attention.
This is particularly true of the expensive milling machines, where the
little saw, if not in perfect order, and not properly set, will not only
do improper work, but injure the machine itself. More lathes are ruined
from using badly ground tools than from any other cause.
In the whole line of tools which the machinist must take care of daily,
there is nothing as important as the lathe cutting-tool, and the
knowledge which goes with it to use the proper one.
Let us simplify the inquiry by considering them under the following
headings:
1. The grinder.
2. The grinding angle.
THE GRINDER.--The first mistake the novice will make, is to use the tool
on the grinder as though it were necessary to grind it down with a few
turns of the wheel. Haste is not conducive to proper sharpening. As the
wheel is of emery, corundum or other quickly cutting material, and is
always run at a high rate of speed, a great heat is evolved, which is
materially increased by pressure
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