Sherline 5000 Mill Assembly Instructions

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would not remain at “0” but would now be a negative
reading. This is caused because the pivot point is located
far enough behind the spindle so that both front and rear
measuring points are still in front of it. Swinging the column
back actually raises both points. The front point raises more
than the back point, but both do go up. You will have to
keep tilting the column back and measuring until you get
the same reading front and back. This may require more
movement than you first thought based on the difference
between the initial measurements.
Fine tuning the headstock alignment
ALL SHERLINE MILLS...It is time to make the final
adjustments to the rotating column, but first I'll add a little
more confusion to your life. Remember when I said that
alignment pins are somewhat useless to line up a machine?
Well, as much as I hate to admit it, in a sense we already
have one. It is the alignment key that holds the headstock
assembly square to the column saddle, which is mounted
on the column bed. Removal of this key is what allows you
to pivot the headstock on the Sherline lathes and mills. It is
one of the features that make our machines easy to use,
versatile and very adaptable. It is also another thing you
have to consider when searching for “perfect” alignment.
If you have more than one key, try not to mix them up
because they are matched during assembly to fit as closely
as possible. I have found the best way to deal with this
potential problem is to push the head square against the
key before tightening the cone point screw that locks the
headstock in place. If you ever want to check alignment of
the key to the column bed, mount a dial indicator in the
spindle. Raise and lower the head while reading the vertical
edge of a precision square. (See Figure 21.) Adjust the
rotating column until there is no error as the indicator moves
up and down the square. Now read the table with the
indicator. If the slot and key are perfect there shouldn't be
FIGURE 20—Squaring the fore and aft pivot movement
of the column with the Y-axis. (See the hint in the section
on squaring the X-axis above for a way to keep the tip
of the indicator from dropping into the T-slots.)
ADJUST FORE/AFT MOVEMENT
WITH CENTER ADJUSTMENT SCREW
ON ALIGNMENT BLOCK
LOCK ADJUSTMENT
IN PLACE WITH
11/16" FLANGE NUT
FIGURE 19—Squaring the left to right rotation of the
column with the X-axis
can be moved using the adjustment screw in the alignment
block but there is no slop in the assembly. The tilt is harder
to set because the spindle doesn't rotate at the pivot point,
but once you understand this, the task becomes simpler.
This is explained in the example that follows. The alignment
block adjustment screw helps make fine adjustments in this
direction easy. With the block in place and the flange nut
loose, the entire assembly is kept from falling forward by
the adjusting screw. This block can be left in place unless
the ram is completely retracted or the column is tilted back
at an angle that interferes with the block. With the indicator
still held in the spindle, take readings parallel with the Y-
axis near the front and rear edges of the table. Raise or
lower the column with the alignment block adjusting screw
until the readings are the same front and rear. Remember
the location of the pivot point as you take these
measurements and allow for it. (See example below.)
MODEL 5000-SERIES MILLS...This axis is not adjustable
on the 5000-series mills, but it can be checked in the same
manner. Again, factory alignment should be quite good, but
a slight amount of adjustment can be obtained by loosening
the two screws that hold the column to the base and
shimming the column at the front or back with thin metal
shim stock* as needed. Recheck your X-axis alignment
after shimming.
*Hint: Shim stock can be purchased from most tooling
supply catalogs. If you don't have metal shim stock available,
cigarette paper or business card stock can be used as a
temporary substitute depending on thickness needed.
Example:
If the indicator reading is larger at the front of the table
than the back, then that means the column must be tilted
back. Say your reading is “0” at the back and .010" (.25
mm) at the front. If you tipped the column back until the
indicator read zero at the front, the reading at the back