Sherline 5000 Mill Assembly Instructions

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CLIMB MILLING ADVANTAGES AND DRAWBACKS
Though you will almost always use conventional milling,
climb milling can create a better finish in two ways. First,
the lightest part of the cut is at the end of the cut. Second,
the chips are tossed from the cutting area and do not affect
the finish.
The major problem with machining in this direction is that
the cutter may actually do just that—climb up on the part
and break. Also, when a climb cut is first started, the work
has to be pushed into the cutter. Then the cutting action
pulls the backlash out of the table leadscrew, and a heavier
cut is taken than planned. If you understand and
compensate for these drawbacks, climb milling can be used.
However, for those new to milling, it is best to try and plan
your cuts so that the end mill is cutting in the conventional
manner.
WORKING TO SCRIBED LAYOUT LINES
A common practice when working with a mill is to lay out
the hole centers and other key locations using a height gage
and a surface plate. A coloring (usually deep blue) called
layout fluid or “Dykem” is brushed or sprayed on a clean
surface of the part. A thin layer is best because it dries
quicker and won’t chip when a line is scribed. The purpose
of this fluid is to highlight the scribed line and make it
easier to see.
Don’t prick-punch the scribed, crossed lines representing
a hole center. Using a center drill in the mill spindle and a
magnifying glass, bring the headstock down until the center
drill just barely touches the scribed cross. Examine the
mark left with a magnifying glass and make any corrections
needed to get it perfectly on center. You should be able to
locate the spindle within .002" (.05 mm) of the center using
this method.
Once the first hole is located in this manner, the additional
holes can be located using the handwheels. (This is where
the optional resettable “zero” handwheels are useful.) Now
the scribe marks are used as a double check and the
handwheels take care of the accuracy. Don’t forget the
rules of backlash—always turn the handwheels in the same
direction as you go from one point to the next.
USING A DIAL INDICATOR
(NOTE: For more on use of a dial indicator to square up
your mill, see pages 13-16.)
The basis of most accurate machining involves the use of a
“universal dial test indicator”; a small, inexpensive indicator
which is calibrated in .001" or .01 mm divisions. An indicator
with a large face or one that reads in finer divisions is not
necessary for use with this mill. Three major tasks that can
be accomplished with an indicator are:
1. Checking the squareness of a setup.
2. Finding the center of a hole.
3. Aligning the work with the machine.
A vise can be mounted or a part can be clamped down
exactly parallel with the machine slides by holding the test
indicator stationary and moving the slide with which you
wish to align the part. When “indicating in” a vise, always
take the reading on the fixed jaw. To start with, use
approximately .005" indicator deflection from neutral.
Remember that excessive pressure can cause inaccurate
readings. Also, try to keep the indicator finger at a
FIGURE 54—Indicating in the jaws of a vise. Shown is
a Starrett “Last Word” Indicator. Starrett gages are
available in numerous sizes and types. They are
manufactured in Athol, Massachusetts and can be
purchased from most industrial dealers.
FIGURE 55—Indicating in the center of a hole