Sherline 5000 Mill Assembly Instructions

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ADJUSTMENT AND USE OF THE TWO-PIECE TAILSTOCK
The brass tailstock gib should be adjusted so that it is equally
tight at both ends and slides easily on the bed dovetail when
the adjustment screw is loosened. As the brass gib wears,
any play that develops can be adjusted out by loosening the
two set screws, readjusting the two button head screws
and then relocking the set screws. To lock the tailstock in
place on the bed,
tighten the center
socket head cap
screw. Do not
overtighten.
ADJUSTMENT SCREWS
TAILSTOCK CASE
ADJUSTMENT LOCKING
SET SCREWS
LOCKING SCREW
BRASS GIB
Only someone new to machining would talk about “perfect”
alignment. Machinists speak instead in terms of
“tolerances,” because no method of measurement is totally
without error. We believe the tolerances of your machine
are close enough for the work for which it was intended;
however, for those searching for maximum accuracy, here
are some tips for maximizing the accuracy of your machine.
Loosen the headstock, push it back evenly against the
alignment key and retighten. This will maximize the accuracy
of the factory setting. To achieve greater accuracy, you
will have to be willing to sacrifice one of the better features
of your lathe or mill; that is, its ability to turn tapers and mill
angles in such a simple manner.
HEADSTOCK—If you choose total accuracy over versatility
or need it for a particular job, proceed as follows. Remove
the headstock and clean any oil from the alignment key
and slot and from the area of contact between bed and
headstock. Replace the headstock, pushing squarely against
the key and retighten. Take a light test cut on a piece of
1/2" to 3/4" diameter by 3" long aluminum stock held in a 3-
jaw chuck. Use a sharp-pointed tool to keep cutting loads
low so as not to cause any deflection of the part. Measure
the diameter of both machined ends. If there is a difference,
the headstock is not perfectly square. Now, without removing
the key, tap the headstock on the left front side (pulley end)
if the part is larger at the outer end. Tap on the right front
side (chuck end) if the part is larger at the inner end.) You
are trying to rotate the headstock ever so slightly when
viewed from the top until the machine cuts as straight as
you can measure. There should be enough movement
available without removing the key, as its factory placement
is quite accurate.
Take another test cut and remeasure. Repeat this procedure
until you have achieved the level of perfection you seek.
Then stand the lathe on end with the alignment key pointing
upward and put a few drops of LocTite™ on the joint
between key and headstock. Capillary action will draw the
sealant in, and when it hardens, the key will be locked in
place. We prefer this method to “pinning” the head with
1/8" dowel pins, because it offers you the option to change
your mind. The headstock can be removed by prying with
a screwdriver blade in the slot between the bottom of the
headstock and the lathe bed to break the LocTite™ loose
should you wish to be able to rotate the headstock again.
TAILSTOCK—To maximize the machine’s tailstock alignment,
first make sure that there are no chips caught in the dovetail
of the bed and no chips or dents in the taper of your tailstock
center. Now put a 6" long piece between centers and take
a long, light test cut. Measurements at either end will tell
you if you need to use an adjustable tailstock tool holder in
the tailstock to achieve better tailstock alignment. We
manufacture adjustable tailstock tool holders (P/N 1202,
1203, 1206) and an adjustable live center (P/N 1201) that
can help you attain near perfect alignment at the tailstock
should your job require it. Instructions for their use are
included with each item.
FIGURE 15—
Components of the
tailstock case and
adjustable gib
If a handwheel has been removed, when reinstalling it, make
sure it is pushed up tightly against its thrust collar before
tightening the set screw. Push the appropriate table or saddle
toward the handwheel to remove any excess play before
tightening. For the mill Z-axis, lift up on the headstock to
remove play.
If excessive backlash develops at the handwheel and thrust
collar junctions, adjust by first loosening the handwheel
set screw. Index (rotate) the handwheel so the set screw
tightens on a different part of the shaft. (If you don’t, it
may tend to keep picking up the previous tightening
indentation and returning to the same spot.) Push the
handwheel in tightly while holding the saddle and retighten
the handwheel set screw.
SADDLE NUT ADJUSTMENT (Lathe and Mill)
Both the lathe saddle and mill column saddle are connected
to their respective leadscrews using a similar brass saddle
nut (P/N 40170/41170 or 40177/41177). The saddle should
first be positioned at the end of its travel as close to the
handwheel as possible. A socket head cap screw attaches
the saddle nut to the saddle, while two set screws align the
nut to the leadscrew. Loosen the cap screw, bring each set
screw into light contact with the saddle nut and retighten
the cap screw. If binding occurs, readjust the set screws.
NOTE: The mill column saddle nut differs from the lathe
leadscrew saddle nut in that it includes a spring-loaded ball
that engages a detent in the saddle locking lever. See page
36 for details on use of the saddle locking lever.
ALIGNING THE LATHE HEADSTOCK AND TAILSTOCK
The versatile feature of Sherline machines that allows the
headstock to be removed or rotated for taper turning and
angle milling keeps us from being able to lock the headstock
in perfect alignment. Precision ground alignment keys and
accurate adjustment at the factory, however, make the
machines highly accurate. In standard form, alignment should
be within .003" (.08 mm). This should be more than
acceptable for most jobs you will attempt.
Want to see some projects built by other Sherline
machinists? Visit www.sherline.com/workshop.htm.