Sherline 5000 Mill Assembly Instructions

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REAMING
Twist drills will generally not drill perfectly accurate sizes,
and very small boring tools are not satisfactory in deep
holes because of their flexibility. Therefore, reaming is used
for holes requiring accuracy within .0005" (.013 mm).
Reamers are available in any standard size, but they are
rather expensive and are generally not purchased to do
one-of-a-kind type work. Use them only when a boring
tool cannot be used because of the depth or size of the
hole. Because of their length, they cannot always be used
on a small lathe.
Reamers are used only to “clean up” a hole. To make an
accurate hole, the work is drilled approximately .010" (.25
mm) smaller than the reamer size. The work should be
slowly rotated and the reamer slowly fed into the hole while
applying plenty of cutting oil. The reamer should be
frequently removed and cleared of chips. Never rotate a
reamer backwards in the work as this can dull the cutting
edges.
FACEPLATE TURNING
The faceplate has three slots that allow work to be bolted
to its surface. Flat work can be screwed directly to the
faceplate. Extra holes can be drilled to suit odd shaped
work unsuitable for a chuck. If the work is mounted off-
center, be sure to counterbalance the faceplate and use very
low RPM. Don’t hesitate to drill holes in or modify the
faceplate as needed to do a particular job. That’s what
they are for. They are inexpensive and you can have several
on hand modified for special jobs.
TAPER TURNING
On some lathes, a taper is cut by offsetting the tailstock.
On the Sherline lathe, taper turning is done by removing
the headstock key and turning the headstock to any angle
away from dead center. To rotate the headstock, the
alignment key must first be removed. Loosen the set screw
in the front of the headstock, and lift the headstock and
motor unit off the locating pin. Tap the alignment key out
of its slot on the bottom of the headstock, and replace the
headstock unit on the pin. While pressing down on the
headstock, rotate it to the angle you desire by referring to
the angle scale on the bed. The base is calibrated in 5°
increments up to 45° on either side of center. When set to
the proper angle, retighten the set screw against the pin to
lock the headstock into position. Tapers can also be cut
without turning the headstock by using a compound slide
(P/N 1270). See page 26 for a description.
Short work can be inserted in a 3- or 4-jaw chuck and
turned as shown in Figure 26. If the headstock is angled
towards the lathe front, the taper will be cut smaller at the
right. Tapered holes can also be bored in work held in the
3- or 4- jaw chuck. To machine a taper on longer stock,
center drill both ends of the bar, set the headstock angle
and mount the part between centers. (See Figure 32.)
TOOL SHAPES AND GRINDING YOUR OWN
CUTTING TOOLS
The shaping of cutting tools to suitable angles for the type
of material and nature of work being performed can be
very important to satisfactory work. When tools become
dull, gently re-grind and preserve the original angles and
shapes. Do not grind the top face of the tools, but confine
sharpening to the end and/or sides except form tools which
are ground on the top surface.
FIGURE 32—Long, shallow tapers can be cut in a
continuous pass by pivoting the headstock to the proper
offset while supporting the other end with the tailstock.
The work is driven by using a drive dog in the faceplate.
The dog acts like a “universal joint” as the drive pin
slides in the faceplate slot.
FIGURE 30—Headstock drilling. The drill turns in the
headstock spindle while the work is held stationary.
FIGURE 31—Turning a taper with the headstock
slightly rotated.