Instruction Manual
Section Five
PHOTO 68 PHOTO 68A
pleting the first operation, tilt the workhead up further for the
secondary or chip clearance angle. The Wheelhead elevation must
again be adjusted so that the O.D. of the wheel will blend in with
tooth face and helix of the cutter. Grind the secondary clearance
until the desired primary land width is achieved. In the photo, since
the wheel is always cutting on the left side of the mill and (FACING
FROM THE FRONT OF THE MACHINE), the workhead has been
swivelled approximately 92 degrees counterclockwise during both pri-
mary and secondary angle settings to give end relief to the end
cutting edges.
(c) The grinding process consists of a gradual surface grinding opera-
tion in the vertical plane using the table action to move the mill end
approximately one half its width across the wheel edge. Under some
conditions, it may not be possible to reproduce the exact alignment
of two opposite cutting edges with the use of one wheel. Further
gashing along the front face of each tooth may be necessary to gain
adequate chip clearance. It is not necessary for opposite cutting
edges to align on a diameter line through the cutter end. The end
mill will cut with these edges off-set from the diameter line. In
general, take no more than .005 inch crossfeed infeed against the
wheel face during rough gumming, using a light cut to finish the job.
8. Salvaging Milling Cutters:
The description of the fluting process parallels that of sharpening a form re-
lieved cutter except for a few important steps. Refer to Figures 68B, 68C,
68D for the following explanation.
1. General Procedure for Salvaging Straight Tooth Milling Cutters:
(a) Mount a saucer wheel with the straight side facing the rear of the
grinder. Mount a wheel guard Place the wheel axis at 90 degrees
to the table, raised sufficiently to allow the bottom of the wheel to
clear the cutter.
(b) Mount the cutter on a workhead arbor or straight arbor between cen-
ters so that when the workhead or arbor is mounted on the table
the cutter teeth on top face to the front of the machine.
(c) Examine the cutter gullet radius, and then dress a somewhat smaller
radius on the inside wheel O.D. edge. Position the cutter under-
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