Hitachi CB 18DBL User manual

Overseas Sales Division
PRODUCT NAME
Hitachi 18 V Cordless Band Saw
Model CB 18DBL C
LIST No.
CB 18DBL: K803
Jul. 2015
CONTENTS
REPAIR GUIDE ----------------------------------------------------------------------------------------------------------------1
1. Precautions on disassembly and reassembly ------------------------------------------------------------1
2. Precautions on disassembly and reassembly of the battery charger -----------------------------13
STANDARD REPAIR TIME (UNIT) SCHEDULES -------------------------------------------------------------------14
Page

-1-
• Removal of the band saw blade
WARNING: Be sure to remove the battery from the main body before starting repair or maintenance
work. If the switch is activated inadvertently with the battery still mounted on the main
body, the motor may turn unexpectedly and could cause serious injury.
1. Precautions on disassembly and reassembly
[Bold] numbers in the description below correspond to the item numbers in the parts list and the exploded
assembly diagrams for the Model CB 18DBL.
First, be sure to remove the saw blade from the main body to prevent damage to the cutting edges of the
saw blade and avoid personal injury due to the saw blade.
1. Removal of the band saw blade
NOTE: Wear leather gloves before handling the band saw blade to protect your hands from injury
caused by sharp cutting edges. Carefully remove the band saw blade from the main body in
a slow manner to avoid personal injury caused by suddenly ejected band saw blade.
(1) Gently turn the Tension Lever [33] to loosen as shown in the figure below.
(2) Loosen the two Bolts M5 x 16 [80] with the Hex. Bar Wrench 4 mm [501].
NOTE: The Bolt M5 x 16 [80] is retained by the O-ring [77].
(3) Push the claws of Blade Pulley Cover (A) [74] and Blade Pulley Cover (B) [73] to open them.
(4) Slowly turn Blade Pulley (A) [72] or Blade Pulley (B) [71] by hand until the Band Saw Blade [66] comes
out from the top edges of the blade pulleys. Then remove the Band Saw Blade [66].
Disassembly
[33]
Loosen
Claws
[74] [73]
[72] [71]
[66]
Top edge of the
blade pulley
The band saw
blade comes out.
REPAIR GUIDE
[501]
[80]
[66]

-2-
• Removal of blade pulleys (A) and (B) and blade pulley rubbers
2. Removal of blade pulley (A) and blade pulley rubber
(1) Loosen the Bolt M6 x 16 [65] and remove the Spring Washer M6 [31], Washer (A) [64] and Blade Pulley
(A) [72] from Pulley Shaft (A) [23].
(2) Remove the Blade Pulley Rubber [70] from Blade Pulley (A) [72].
3. Removal of blade pulley (B) and blade pulley rubber
(1) Loosen the Bolt M6 x 16 [65] and remove the Spring Washer M6 [31], Washer (A) [64] and Blade Pulley
(B) [71] from the Slide Plate [45].
NOTE: Be careful not to lose the Flat Washer [63] that might be attached to the side of the Blade
Pulley (B) [71] when removing Blade Pulley (B) [71].
(2) Remove the Blade Pulley Rubber [70] from Blade Pulley (B) [71].
NOTE: The Needle Bearing [69] is press-fitted in Blade Pulley (B) [71]. Replace the Needle
Bearing [69] with new one if it is damaged.
[65]
[31]
[64]
[72]
[70]
[64]
[31]
[65]
[71]
[70]
[63]
[23]
[45]
[40]
[69]
[28]

-3-
• Disassembly of bearing holder (A) ass'y and bearing holder (B) ass’y
4. Disassembly of bearing holder (A) ass'y
(1) Loosen the Screw D4 x 16 [8] and the Screw D4 x 20 [76]. Remove Cover Holder (A) [79] and Bearing
Holder (A) Ass'y [61] from the Frame [40].
(2) Loosen the two Bearing Pins (B) [55] with a flat-blade screwdriver and remove the two Spring Washers
M6 [54], two Bolt Washers M6 [53], four Ball Bearings 606VV [52] and two Washers M5 [51] from
Bearing Holder (A) [62].
(3) Remove the Bearing Pin [56], two Bolt Washers M4 [57] and Roller 604VV [58] from Bearing Holder (A)
[62].
5. Disassembly of bearing holder (B) ass'y
(1) Loosen the Screw D4 x 16 [8] and Screw D4 x 20 [76]. Remove Cover Holder (B) [75] and Bearing
Holder (B) Ass'y [49] from the Frame [40].
(2) Loosen two Bearing Pins (B) [55] with a flat-blade screwdriver and remove the two Spring Washers M6
[54], two Bolt Washers M6 [53], four Ball Bearings 606VV [52] and two Washers M5 [51] from Bearing
Holder (B) [50].
(3) Remove the Bearing Pin [56], two Bolt Washers M4 [57] and Roller 604VV [58] from Bearing Holder (B)
[50].
[40]
[62]
[61]
[55]
[54]
[53]
[52]
[51]
[49]
[55]
[50]
[54]
[53]
[52]
[51]
[56]
[57]
[58]
[75]
[8]
[76]
[79]
[8]
[76]
[58]
[57]
[56]

-4-
• Disassembly of the handle set and housing set
6. Removal of blade pulley covers (A) and (B)
(1) Remove the two Retaining Rings (E-type) for D3 Shaft [68] with long-nose pliers and pull out the two
Pins D4 [67] from the Frame [40].
(2) Remove Blade Pulley Cover (A) [74] and Blade Pulley Cover (B) [73] from the Frame [40].
(3) Remove the O-rings [77] from Blade Pulley Cover (A) [74] and Blade Pulley Cover (B) [73]. Remove
the Bolt M5 x 16 [80] and Washer M5 [78].
7. Disassembly of the handle set
(1) Loosen and remove the two Screws D4 x 16 [8] at the front of the main body.
(2) Turn the main body upside down. Loosen and remove the eight Screws D4 x 16 [8] and remove the
Handle Set [2] from the Frame [40]. Then disassemble the Handle Set [2].
NOTE: Be careful not to lose the internal parts (especially the Spring [5] attached to the Knob [6])
when disassembling the Handle Set [2].
8. Disassembly of the housing set
(1) After removal of Blade Pulley (A) [72], loosen and remove the three Screws D4 x 16 [8].
(2) Turn the main body upside down. Loosen and remove the four Screws D4 x 20 [29] and remove the
Housing Set [12] from the Frame [40].
(3) Loosen and remove the four Screws D3 x 20 [35]. Then disassemble the Housing Set [12].
[40]
[2]
[3]
[5]
[6]
[12]
[29] [28]
[14]
[35]
[8]
[8]
[8]

-5-
• Disassembly of the rotor pinion set and gear box ass'y
9. Disassembly of the rotor pinion set and gear box ass'y
(1) After disassembly of the Housing Set [12], remove the Stator FET PCBAss'y [13], Rotor Pinion Set [14]
and the Gear BoxAss'y [28] from the Housing Set [12].
(2) Pull out the Rotor Pinion Set [14] from the Gear Box Ass'y [28] and then pull out the Rotor Pinion Set
[14] from the stator of the Stator FET PCB [13].
(3) Loosen the three Screws D4 x 16 [17] inside the Gear BoxAss'y [28] and remove the Gear Case Cover
[18].
(4) Remove the Lock Washer [19], three gears of Planet Gear (A) Set [20], Pinion (B) [21], three gears of
Planet Gear (A) [20] and Ring Gear [22] from the Gear Case [25].
(5) Remove the Retaining Ring for D15 Shaft [27] from Pulley Shaft (A) [23] by using a retaining ring puller.
(6) Push Pulley Shaft (A) [23] on the retaining ring side to remove it together with the Ball Bearing 6902VV
[24] (on the gear chamber side) and Ring [26] from the Gear Case [25].
(7) Push the Ball Bearing 6902VV [24] (on the retaining ring side) on the gear chamber side of the Gear
Case [25] to remove it.
[12]
[40]
[13]
[14]
[28]
[17]
[18]
[25]
[19]
[20] [21]
[20]
[22]
[27]
[23]
[24]
[24]
[26]

-6-
• Disassembly of the stator FET PCB
10. Removal of the stator FET PCB
(1) After disassembly of the Handle Set [2] and Housing Set [12], remove the Stator FET PCB [13], Rotor
Pinion Set [14], and Gear BoxAss'y [28] from the Housing Set [12].
(2) Pull out the Rotor Pinion Set [14] from the Gear Box Ass'y [28] and then pull out the Rotor Pinion Set
[14] from the stator of the Stator FET PCB [13].
(3) Peel silicon rubber off the heads of the two Screws M3.5 x 6 [9] and then loosen and remove them.
Remove the connector between the Stator FET PCB [13] and the Switch [4] to remove the Switch [4].
(4) Pull out the Dial [10] from the volume PCB ass'y of the Stator FET PCB [13].
NOTE: Be careful not to lose the O-ring [11] attached to the Dial [10].
[12]
[2]
[13]
[40]
[14]
[
28
]
Stator
[9] Connector
[4]
Volume
PCB ass'y
[10]
[11]

-7-
• Removal of the tension lever and slide plate
11. Removal of the tension lever
(1) Loosen the Screw M6 x 16 [30] and remove the Tension Lever [33], Spring Washer M6 [31] and Bolt
Washer M6 [32] from the Lever Shaft [37].
(2) Loosen and remove the four Screws D4 x 16 [8] to remove the Tension Lever Holder [34] from the
Frame [40].
(3) Remove the Ring [36], Lever Shaft [37], Sleeve [38] and Tension Spring [46] from the Frame [40].
NOTE: The Sleeve [38] may be attached to the Lever Shaft [37] with grease.
12. Removal of the slide plate
(1) After removal of Blade Pulley (B) [71], remove the Flat Washer [63] from pulley shaft (B) in the Slide
Plate [45].
NOTE: The Flat Washer [63] may be attached to Blade Pulley (B) [71] with grease.
(2) Loosen and remove the four Screws D4 x 16 [8] together with four Washers (B) [41] from the Frame
[40].
(3) Remove the Slide Plate [45] from the Frame [40].
NOTE: The Lock Nut M5 [48] and Screw M5 x 10 [47] are attached to the Slide Plate [45].
(4) Remove the four Collars [44] and Protection Plate [43] from the Frame [40].
[40]
[71]
[72]
[63]
[45]
[30]
[31]
[32] [33]
[31]
[34]
[36]
[37]
[38]
[46]
[8]
[41]
[43]
[44]
[48]
[47]

-8-
• Silicone application points
Reassembly can be accomplished by following the disassembly procedures in reverse. However, special
attention should be given to the following items.
1. Reassembly of bearing holder (A) ass'y
(1) Coat Threebond 1401B to the threaded portions of two Bearing Pins (B) [55].
(2) Insert a 0.6-mm thickness gauge between the Ball Bearings 606VV [52] and lightly press the Ball
Bearings 606VV [52] each other. Then tighten two Bearing Pins (B) [55].
2. Reassembly of bearing holder (B) ass'y
(1) Coat Threebond 1401B to the threaded portion of two Bearing Pins (B) [55].
(2) Insert a 0.6-mm thickness gauge between the Ball Bearings 606VV [52] and lightly press the Ball
Bearings 606VV [52] each other. Then tighten two Bearing Pins (B) [55].
3. Reassembly of the handle set and the housing set
When reassembling the Handle Set [2] and Housing Set [12], be careful not to catch the internal wires of
the stator ass'y, controller ass'y, LED ass'y, volume ass'y, indicator ass'y, capacitor ass'y, and battery
terminal in the Stator FET PCB [13] between handles (A) and (B) of the Handle Set [2], between housings
(A) and (B) of the Housing Set [12], and the Frame [40].
NOTE: Refer to "5. Reassembly of the power supply unit and stator FET PCB" on the next page.
4. Reassembly of the gear box ass'y
(1) Replace all the six gears of Planet Gear (A) Set [20] with new ones.
(2) Apply Shin-Etsu Silicone KE347B to the points shown in the figure below before mounting the Gear
Case Cover [18] to the Gear Case [25].
(3) After reassembly, check that Pulley Shaft (A) [23] turns smoothly.
Reassembly
Gear case side
[25] [19]
Apply about 0.8 gram of silicone to the edge of the Lock
Washer [19] (entire circumference) to fill the gap with the
Gear Case [25].
NOTE: Apply silicone to the stopper portions of the
Lock Washer [19] so that the concave portions
are completely covered.
Stopper portions of [19]

-9-
• Mounting the stator FET PCB to the housing set
• Mounting the housing set to the frame
5. Reassembly of the power supply unit and stator FET PCB
(1) Mount the Dial [10] to the volume PCB ass'y in the Stator FET PCB [13] according to the following
procedure.
a) Apply 0.5 gram of NPC SEP-3A grease to the circumference of the O-ring [11] and fit the O-ring [11]
to the Dial [10].
b) Insert the Dial [10] a little into the volume PCB ass'y in the Stator FET PCB [13] and turn it
counterclockwise until it stops.
c) Pull out the Dial [10] from the volume PCB ass'y. Align the mark “1” on the Dial [10] with the
protrusion on the cover of the volume PCB ass'y and then fully insert the Dial [10] into the volume
PCB ass'y.
d) Fully turn the Dial [10] clockwise. Check that the mark “A” on the Dial [10] aligns with the protrusion
on the cover.
e) If not aligned, repeat the above steps b) to d).
(2) Fit the flange portion of the stator in the Stator FET PCB [13] in the concave portion of housing (A) of the
Housing Set [12] when mounting the Stator FET PCB [13] to housing (A). Fit the two 16AWG internal
wires (red and black) and sixteen 28AWG internal wires (white and black) of the Stator FET PCB [13]
into the groove of housing (A) of the Housing Set [12] as shown in the figure below.
(3) When mounting the Housing Set [12] to the Frame [40], tighten the three Screws D4 x 16 [8] on the
Frame [40] side first and then tighten the four Screws D4 x 20 [29] on the Housing Set [12] side.
[28]
[13]
[14]
Housing (A) of [12]
Flange portion of the stator
Fit the internal wires into this groove.
[40] [28] [8]
Align the hole of the Gear Box Ass'y [28]
with the hole of the Frame [40].