Instruction Manual
Section Five
work-mounting device into the workhead spindle. Mount the work and check
its runout with an indicator. Very thin bushings may have to be held with the
aid of a special bushing chuck or by end pressure to avoid distortion.
D. Loosen the handle screws on the right side of the Wheelhead dovetail slide
and move the Wheelhead forward enough so that there will be adequate cross-
feed capability while aligning the wheel with the work hole. Tighten the
dovetail handle screws and make sure all other Wheelhead swivels are tight.
E. Using the machine height gauge, put the centerline of the wheel spindle at
the same height above the table as the centerline of the workhead spindle.
The Wheelhead spindle axis is also placed parallel to the table travel by putting
the swivel(s) at 0. It is also important to align the centerline of the work-
head spindle with the direction of the table travel. Put the workhead fixture
base at 0 degrees and make adjustments with the table taper adjusting screws
at the right end of the table. This may be done during grinding, starting with
a table adjustment reading of 0, but it is more accurate to use an indicator
and a test arbor in the workhead spindle before attaching the workholding
device and the work.
F. Before starting the wheel spindle or the workhead, traverse the table enough
to the right to set a depth stop on the table. The wheel should not protrude
from the hole more than ¼ to ½ of its length. When using a power table
travel machine, set a stop for travels in both directions.
C. Start the machine wheel spindle and true and dress the wheel. If the wheel
is dressed on the side facing the operator, then this same side should be used
to grind the work piece. Start the workhead and operate it in a direction
opposite to that of the wheel at the point of grind. Move the wheel into the
work hole, advance the Crossfeed until contact, turn on coolant, and use the
same grinding practices as explained in I and III of this chapter.
III. GRINDING RULES APPLICABLE TO CYLINDRICAL GRINDING
A. A loaded wheel will mar the surface of the work rather than finish it. With
a slow work speed, a light cut, and a hard wheel, the wheel will dull easily and
become glazed. Increasing the work speed tends to make the grinding wheel
act softer, and vice versa. A glazed wheel is not sharp and eventually will
rub, burn, and destroy the work.
B. A slow work speed combined with a soft wheel is better than a fast work
speed and a hard wheel because there is less tendency to heat and distort the
work. However, neither extreme is desirable.
C. When grinding hard materials, use a soft wheel or increase the work speed so
that the dulled grains will wear off evenly.
D. Work of a large diameter calls for a softer wheel and slower work speed than
does work of a small diameter, and vice versa.
E. Cracks, checks, and burns caused by excessive heat generation may be due
to too hard a wheel, too heavy infeed, too slow work speed, insufficient
grinding fluid, a glazed or dulled wheel, or an improperly dressed wheel.
Keep the wheel dressed to maintain a free cutting action. Us an adequate
coolant stream at the point of contact.
F. The table traverse should be constant and not stopped during the process of
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