10
Reverse rotation (rapid advance lever depressed) should be
5,700 R.P.M. minimum.
Desired forward rotor speeds (R.P.M.)
Drill Spindle
R.P.M.
75
100
120
150
190
240
310
390
480
585
660
825
960
1165
1,500
VARIABLE SPEED TOOLS
For disassembly of drill head and gear trains, see page 7 & 8.
DISASSEMBLY—VARIABLE SPEED MOTOR AND
GOVERNOR UNIT
Clamp handle in vise with motor housing upwards. Unscrew
both motor housing 382509 and turnbuckle collar 382508 in
unison from handle. Keep governor center 382619, shims, and
bearing 847095 together as a unit. Replace this bearing if it is
damaged.
CAUTION: Do not lose these shims. The same shims must be
used for reassembly.
Tap motor and motor housing on wooden bench top to remove
motor unit. Hold either the pinion gear 617609 or rotor nut
382522 and unscrew (left hand threads) governor assembly.
Remove rear bearing 864522, bearing plate 867369, cylinder
867377 and three (3) rotor blades 382520. Note: Check
function of rotor blade kick-out approximately 1/ 8". If required,
the spring cap 382514 must be drilled and tapped for removal.
Clamp body of the rotor in vise and unscrew pinion 617609 or
nut 382522. To remove governor weights from spider, press
governor weight pins 867184 out.
DISASSEMBLY—VARIABLE SPEED MOTOR BACKHEAD
WARNING: Pressure cap 382507 must not be unscrewed
while the motor backhead is connected to air supply. This
cavity is supplied with high pressure air whenever the backhead
is connected to the air system.
Remove pressure cap, spring 864681, ball 812156, and pin
847031. Rapid advance valve 382501 may be removed by
unscrewing valve cap 382502 and removing retainer ring
869460. The rapid advance lever 382503 may be removed by
unscrewing (3/16" hex) flat head cap screw 382504. Remove
button head screw 844288. That will release the governor
valve 382618. Remove governor spring 382238, shims 202349,
auxiliary spring cap 382264, spring 382271 (inside cap) and
guide stud 382620. Caution: Do not lose those shims. The
same shims must be used for reassembly. Remove set screw
382512 and speed cam. Remove detent pad 382627, set
screw 867502, and spring 512275 for inspection.
DISASSEMBLY—HANDLE Same as on page 8.
REASSEMBLY—GENERAL Same as on page 8.
REASSEMBLY—HANDLE Same as on page 8.
REASSEMBLY—VARIABLE SPEED MOTOR BACKHEAD
Install rapid advance valve and related parts (same as single
speed tool). Lubricate O-ring 844307 on speed cam. As-
semble spring 512275, set screw 867502, and detent pad
382627 onto backhead. Install speed cam and lock set screw
382512. Install governor parts in reverse order of disassembly
and secure with button head screw.
REASSEMBLY—VARIABLE SPEED MOTOR AND
GOVERNOR
Assemble governor weights 867189, pins 867184, and spider
382621. Seat front rotor bearing 842870, in front bearing plate
382521, and support bearing on its outer race. Measure from
face of the bearing plate to bearing inner race. Select or fit by
sanding a rotor collar .002" longer than this measurement.
Install rotor collar (chamfered side first) and bearing plate
assembly on rotor. Tighten rotor pinion 617609, or rotor nut
382522, to approximately 35 ft. Ibs. (47.4 Nm). When installing
the rotor blades 382520, be certain that the rotor blade kickout
pins are working. Assemble the three (3) rotor blades, cylinder
867377, rear bearing plate 867369, rear bearing 864522, and
governor assembly. Tighten (left hand threads) governor
assembly almost as tight as pinion gear or front rotor nut.
VARIABLE SPEED MOTOR HOUSING AND
RUNNING MOTOR
Work the motor unit into the housing and clamp the housing
into a vise with the governor assembly upward. Assemble the
governor center 382619, shims, and bearing 847095, with the
governor weights leaning inward.
Set the speed adjustment to one of these settings:
125 RPM
240 RPM
480 RPM
900 RPM
Rotor Speed
R.P.M.
5,800
-
7,200
-
8,870
-
11,300
-
7,100
-
8,900
-
11,100
-
6,900
-
8,600
-
10,200
-
11,600
-
7,400
-
8,600
-
10.200
-
13,000 Min.
6,200
7,760
9,400
12,100
7,500
9,350
12,200
7,450
9,100
11,100
12,400
7,900
9,130
11,100
(190V)
(375V)
(780V)
(1500V)