Sherline 5000 Mill Assembly Instructions

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BORING HEAD (P/N 3054/3049) AND BORING TOOLS
The main purpose of the boring head is to eliminate the
need for a large inventory of drills and reamers. A small
milling machine would not have the power or rigidity to
turn a one-inch diameter drill even if one could be obtained
that would fit. However, holes of even larger diameters
can be accurately bored to size with a little patience and
care.
FIGURE 66—Boring
Head and Boring Tool.
Boring tool P/N 3061 is for
1/4" (6.4 mm) minimum
diameter by .60" (15.2
mm) maximum depth hole.
P/N 3063 is for 5/16" (7.0
mm) minimum diameter by
1.0" (25 mm) maximum
depth hole. Both have a
3/8" diameter shaft. P/N 3064 is similar in size to P/N
3063 but longer and will work to a maximum depth of
1.5" (38.1 mm).
Boring heads for the mill work on the same cutting principle
as lathe boring, except that the cutting tool turns while the
work remains stationary. (In the case of a lathe, the work
turns and the cutter remains stationary.) The boring head
is designed to employ round cutting tools with a 3/8" shank.
Sherline offers three boring tools with sizes and lengths
appropriate for the Sherline mill. It is sometimes advisable
to remove excessive tool shank length from standard (non-
Sherline) 3/8" boring tools in order to improve rigidity.
(See Figure 52, page 32 for a boring tool in use.)
Tool sizes are listed indicating the smallest diameter hole
that can be bored and the maximum depth that can be cut.
For best results, use the largest diameter possible with the
shortest lengths. A .010" cut represents a good starting
point.
If boring a hole where a flat bottom is required, it is
advisable to stop the down-feed at about .002" above the
desired depth, turn off the motor and cut the remaining
distance by hand-turning the spindle to eliminate any
possibility of chatter.
FLY CUTTERS (P/N 3052 AND P/N 7620)
For machining flat surfaces, the fly cutter shown in the
Sherline Tool & Accessory Catalog is recommended. It is
imperative that the tool be used with utmost care. EYE
PROTECTION IS A MUST, and the work as well as the
cutting tool must be properly held. The big advantage of a
fly cutter is its ability to take light cuts up to 2" wide and
to give an excellent surface finish. It is ideal for squaring
up work. Also, the machining stresses are lower than one
might imagine, because, unlike an end mill, very little
crushing action takes place at the cutting edge. Fly cutting
tools look like left-hand lathe tools, and, although the fly
cutter (P/N 3052) comes with a brazed carbide tool, high-
speed tools work quite well and can be sharpened on any
grinder. (See Figures 67 and 68)
FIGURE 65—Mill collet set
FIGURE 68—Typical setup for fly cutting
DRILL CHUCK (P/N 3072) AND CENTER DRILLS
The 1/4" drill chuck available for this vertical mill is supplied
complete with a #1 Morse arbor and a drawbolt to hold it
securely in place. Drilling can be accomplished by raising
and lowering the entire head with the vertical feed
handwheel. This allows for very accurate control of feed
rate and hole depth. For accurately located holes we again
stress the importance of using center drills.
Drills should be kept in excellent condition, either by
replacement or proper resharpening. Good quality high-
speed steel drills should be employed. A dull or improperly
sharpened drill can cut oversize by as much as 10%. When
you start to drill, the initial penetration should be no more
than twice the diameter of the hole before you retract the
drill, clear the chips and add coolant with the tip of a small
brush. From then on, do not try to drill deeper than the
FIGURE 67—Fly cutters and drawbolts
P/N 3052 FLY CUTTER
USES A 1/4" SQUARE HSS
OR BRAZED CARBBIDE
CUTTING TOOL
P/N 7620 FLY CUTTER
WITH CARBIDE INSERT