Sherline 5000 Mill Assembly Instructions

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DETERMINING DEPTH OF CUT
There are no firm rules other than common sense for
determining depth of cut. A .030" cut depth with a 3/16"
end mill in aluminum could be considered light, but .003"
cut depth in steel with a 1/32" diameter end mill would
break the cutter. Start with very light cuts and gradually
increase the depth until satisfactory results are achieved.
Try to develop the skill of knowing how much of a cut is
satisfactory without breaking the cutter or damaging the
work.
Note that regular end mills should not be used for drilling;
however, they may be employed to enlarge an existing hole.
The cutting edges deserve more respect than those of drills
even though similar in appearance; they are designed to
cut with their sides. Handle and store them with care.
WORK ACCURATELY
It should be remembered that a good machinist is capable
of making a part to much closer tolerances than those of
the machine with which he is working. The accuracy of
the parts you make is limited only by your skill as a
craftsman and the quality of your measurement equipment.
Accuracy should be the ultimate goal of every machinist!
CUTTING SPEEDS FOR MILLING
SPEED ADJUSTMENT CHART
SPINDLE RPM = 3.82 x S.F.M.
D
S.F.M. = The rated Surface Feet per Minute for milling. For drilling,
use 60% of the rated surface feet.
RPM = The rated spindle speed in Revolutions Per Minute
D = The Diameter of work in inches
FIGURE 59—Formula for adjusting spindle speed for
cutting a given diameter.
NOTE: To estimate RPM, remember that the speed range
of your vertical mill is from 0 to 2800 RPM. (The lowest
usable speed is about 70 RPM, so we use that in our
specifications. To obtain much more torque at the lower
speed ranges, the drive belt can be switched to the smaller
diameter positions on the spindle and drive pulleys.)
Therefore, in the normal belt position, half speed is
approximately 1450 RPM and so on. You can estimate
these speeds by a combination of the setting on the speed
control knob and the sound of the motor itself. When using
the optional digital readout (P/N 8100), the exact RPM is
displayed constantly on the LCD screen.
END MILLS
End mills are the standard cutting tools used on a vertical
mill. We recommend 3/8" shank end mills held in the 3/8"
end mill holder (P/N 3079). One of the benefits of 3/8"
end mills is that they are available in a large range of sizes.
The end mill is held with a set screw on its flat surface,
and it can be easily changed. They are also lower in price
than miniature cutters because of their popularity.
You can also use miniature series end mills having 3/16" or
1/4" shank sizes which should be held in collets or end mill
holders sized for those tools. End mills held in collets must
be single-ended, while end mill holders are capable of
holding double-ended end mills. We recommend using 2-
flute, high-speed steel (HSS) end mills for aluminum because
the flutes are less prone to clog with chips. Use 4-flute
cutters for cutting steels with lower RPM. The solid carbide
tools are not suggested since they are very expensive and
the cutting edges will chip unless used with heavy-duty
production equipment.
FIGURE 60—A typical 2-flute end mill.
As a convenience to our customers, Sherline keeps in
inventory many of the popular sizes of end mills that are
appropriate for use on our machines. See the “Cutting Tools
Price List” for selection. End mills may also be purchased
from your local industrial machine shop supply outlet (see
the yellow pages under “Machine Shop Supplies”) or from
mail order industrial suppliers.
Because small diameter cutters (less than 1/8") are quite
fragile, the largest diameter cutter possible for the job
FIGURE 58—A digital readout makes life easier for
the machinist. The electronic display reads out to .0005"
and any axis can be reset to “zero” with the push of a
button. It also helps eliminate mistakes due to losing
track of the number of handwheel revolutions on longer
dimensions. As a bonus, the spindle RPM is displayed
at all times. The digital readout or “DRO” is available
for both the lathe and mill.
MACHINING TIP
Use of a tooling plate (P/N 3560) is an inexpensive
way to protect the surface of your mill table while
providing a flat, versatile clamping surface.