Makita BCS550Z Manual

PRODUCT
P 1 /13
Specification
Standard equipment
Optional accessories
Note: The standard equipment for the tool shown above may differ by country.
TCT saw blade 136mm (5-3/8") 30T ............................... 1
Hex wrench ....................................................................... 1
Safety goggle .................................................................... 1
Plastic carrying case.......................................................... 1
Model No.
Description
CONCEPT AND MAIN APPLICATIONS
BCS550
Cordless Metal Cutter 136mm (5-3/8")
Model BCS550 is a MAKSTAR Cordless Metal Cutting Saw,
featuring compact and lightweight design for high maneuverability
and easy handling.
The items listed below in "Standard Equipment" also come with the above items.
H1
H2 L1 L2
W1
W2
Continuous Rating (W)
Voltage (V) Cycle (Hz) Input Output Max. Output (W)
18
3,600
Li-ion
3.0
approx. 22 min. with DC18RA
136 (5-3/8)
51 (2)
Yes
2.4 (5.3)
North American countries: 15.88 (5/8)
Other countries: 20 (13/16)
370
Current (A)
No load speed: rpm= min.-1
Battery
Cell
Capacity: Ah
Charging time
Size of blade:
mm (")
Max. cutting
capacities: mm (")
Net weight*: kg (lbs)
*with Battery BL1830
Diameter
at 0 degree
at 45 degrees
at 50 degrees
Electric brake
Hole diameter
Fast charger DC18RA
Charger DC24SA
Charger DC24SC
Li-ion battery BL1830
Screw M5x20
Compression spring 6
136mm (5-3/8") TCT saw blade 30T
136mm (5-3/8") TCT saw blade 50T
Rip fence (Guide rule)
TECHNICAL INFORMATION
Dimensions: mm (")
Width (W1)
Height (H1)
Length (L1) 348(13-3/4)
180 (7-1/8)
201 (7-7/8)
Height (H2) 145 (5-3/4)
Base Size: mm (")
Width (W2)
Length (L2) 200 (7-7/8)
106 (4-3/16)
This product is available in the following variations.
BCS550
BCS550Z
BL1830DC18RA
NoNo
Model No. type quantity Charger
No All countries
Yes
Plastic
carrying case Offered to
No
BCS550RF
North America
All countries except
North America
1
BCS550RFE 2
Battery

P 2 /13
[2] LUBRICATION
[1] NECESSARY REPAIRING TOOLS
CAUTION: Remove the battery, SAW BLADE from the machine for safety
before repair/ maintenance !
Repair
1R027
1R028
1R031
1R032
1R037
1R356 Bearing plate 10mm (for arbor press)
Bearing setting pipe 18-10.2
Bearing setting pipe 20-12.2
Bearing setting pipe 28-20.2
Bearing setting plate 8.2
Bearing setting plate 20.2
Bearing extractor (2 pcs)
Bearing extractor
1R263
1R269
1R278 Round bar for arbor 4-50
1R281 Round bar for arbor 7-50
Retaining ring S and R pliers Removing/installing Retaining ring
Removing/installing Bearing retainer 14-23
Removing Ball bearing 604ZZ
Removing Ball bearing 604ZZ and 696ZZ
Removing Ball bearing 604ZZ
Supporting Gear shaft when assembling Helical gear 35,
Ball bearing 6900ZZ and Helical gear 15 to Gear shaft
Supporting Bearing box section when removing Helical gear 23,
Sleeve 10, and Ball bearing 6900ZZ from Spindle
Removing Bearing box section
Assembling Helical gear 35 to Gear shaft
Assembling Ball bearing 6900ZZ and Helical gear 15 to Gear shaft
Removing Helical gear 35, Ball bearing 6900ZZ and Helical gear 15
from Gear shaft
Removing Helical gear 15 and Ball bearing 6900ZZ
1R291
Wrench for bearing retainer1R316
Code No. Description Use for
Fig. 1
(viewed from the opposite side)
19
Handle R
Thickness ring
3g to the gear room for Helical gear 23 and Helical gear 15
Surface that contacts Safety cover complete
3g to the gear room located on the opposite side for Helical gear 35
and Pinion gear of Armature shaft
51
Helical gear 23
19
Item No.
Description Portion to lubricate Lubricant
19
51
Apply the following grease to protect parts and product from unusual abrasion:
Makita grease N. No.2 to the following portions designated with the black triangle
Machine oil to the following portions designated with the gray triangle
Safety cover complete
Helical gear 35
Helical gear 15

P 3 /13
[3] DISASSEMBLY/ASSEMBLY
[3] -1. Base
Repair
Sleeve 4
Tapping screw 4x25
Rubber sleeve 6
Pipe 6
Base
Hex lock nut M5-8
Pan head screw M5
Pan head screw M5
Flat head square neck bolt M6x75
Flat head square neck bolt M6x75
Hex nut M6
Stop ring E-8
Flat washer 6
For easy removal of Hex nut M6, loosen Hex nut M6
using Lever 40 as a wrench before removing Lever 40.
Lever 40
Fig. 2 Fig. 3
Fig. 4 Fig. 5
1) Remove Blade cover (transparent part) by unscrewing Tapping screw 4x12. (Fig. 2)
2) Remove Rubber sleeve 6 and Sleeve 4 by unscrewing Tapping screw 4x25. (Fig. 3)
3) Remove the following 5 parts from Flat head square neck bolt M6x75: Stop ring E-8, Lever 40, Hex nut M6,
Flat washer 6, Pipe 6. Swivel Safety cover and pull off the bolt. Remove Pan head screw M5 while fixing
Hex nut M5-8 with Wrench 8. (Fig. 4) Base can now be separated from the machine. (Fig. 5)
Tapping screw 4x12
Blade cover
(transparent)
DISASSEMBLING
Handle and Motor housing
viewed from Motor housing side
Safety cover comp.

P 4 /13
[3] DISASSEMBLY/ASSEMBLY
[3] -1. Base (cont.)
[3] -2. Safety Cover Complete and Bearing Box Section
Repair
1) Do the reverse of the disassembling steps.
2) After assembling Base to the machine, adjust the following portion for smooth adjustment of cut depth:
A. Pan head screw M5 in the hinge portion of Base
Must be tightened so that the machine can move along
Depth guide smoothly without rattling. (Figs. 4 and 5)
B. Lever 40
Must be installed so that it can be locked at an angle of
between 0 and 30 degrees from the centerline towards
Switch side when the cut depth is set to the maximum.
(Fig. 6)
1) Remove Blade cover and Rubber sleeve. (Figs. 2 and 3)
2) By removing Retaining ring WR-26 with 1R291, the following parts can be removed (Fig. 7):
two Spacers (one on the outside and the other on the inside of Safety cover), Safety cover complete,
Tension spring 3, Thickness ring
Note 1: Safety cover complete can be separated from Blade case by unhooking the end of Tension spring 3 from
Blade case.
Note 2: Two Spacers may fall off when Safety cover complete is separated from Blade case.
Be careful not to lose them.
3) By unscrewing two M5x16 Countersunk head screws, Bearing box section can be removed by hand. (Fig. 8)
If cannot be removed by hand, lever off using a pair of 1R263 as illustrated in Fig. 8A.
Note: It is recommended to use cordless impact driver for removing the screws because threadlocker is applied to them.
Fig. 7 Fig. 8
DISASSEMBLING
Retaining ring WR-26
Spacer
Spacer
Thickness ring
Safety cover complete
Countersunk head
screw M5x16
Bearing box section
ASSEMBLING
Fig. 6
Lever 40
Depth guide
Base centerline of Handle
30 degrees
Tension spring 3
Blade case
Fig. 8A
1R263
1R263
Bearing box section

P 5 /13
[3] DISASSEMBLY/ASSEMBLY
[3] -2. Safety Cover Complete and Bearing Box Section (cont.)
Repair
Fig. 11
Fig. 12
1R031
Helical gear 23
Helical gear 23
Spindle
Fig. 10
1R291
Retaining ring S-10
Fig. 9
1R269
Ball bearing 696ZZ
Bearing box section
Spindle
4) Remove Ball bearing 696ZZ from Bearing box section with 1R269. (Fig. 9)
5) Remove Retaining ring S-10 with 1R291. (Fig. 10)
6) Remove Spindle by following the steps below (Fig. 11):
1. Put Bearing box section on 1R031 with Helical gear 23 side up.
2. Remove Helical gear 23 and Sleeve 10 by pressing the end face of
Spindle using arbor press.
3. Apply 1R281 to the end face of Spindle, and press it using arbor press.
Spindle can now be removed from Bearing box section.
Important: Ball bearing 6900DDW in Bearing box section will always
be damaged in these steps.
Do not forget to replace with new one.
7) Attach a pair of 1R041 to vise. Fix Bearing box section in vise.
Remove Bearing retainer 14-23 from Bearing box by turning counter-
clockwise with 1R316. Damaged Ball bearing 6900DDW can now be
removed. (Fig. 12)
1R041
Vise
O ring 26
Bearing retainer
14-23 Ball bearing 6900DDW,
damaged in the previous step
Sleeve 10
1R281
DISASSEMBLING
1R316
Bearing box
Bearing box section
Fit these pins in the groove
of Bearing retainer 14-23.

P 6 /13
[3] DISASSEMBLY/ASSEMBLY
[3] -2. Safety Cover Complete and Bearing Box Section (cont.)
Repair
Spacer
Spacer
Safety cover complete Spacers assembled correctly
to Safety cover complete
Blade side
Tension spring 3
Gear housing side
Fig. 15
Fig. 13 Fig. 14
Thickness ring
Apply machine oil to the outer surface of
Thickness ring for smooth movement of
Safety cover complete.
Bearing box section
1) Assemble Bearing box section by doing the reverse of the disassembling steps, and install it on the machine.
(Fig.8on page 4)
Note: Before assembling Helical gear 23 to Spindle, make sure that O ring 26 is installed on Bearing box
as illustrated to right in Fig. 12 on page 5.
2) Assemble Safety cover complete to the machine.
Note 1: Be sure to assemble two Spacers to Safety cover complete as illustrated in Fig. 13.
Note 2: Do not forget to assemble Thickness ring to Bearing box. (Fig. 14)
Note 3: When linking Safety cover complete to Blade case with Tension spring 3, hook each end of Tension spring 3
as illustrated in Fig. 15.
ASSEMBLING
Blade case
Safety cover complete
Hook this end of Tension spring 3 through
the hole in Blade case from Blade side.
Hook this end of Tension spring 3 through the hole
in Safety cover complete from gear housing side.

P 7 /13
Repair
1R278
1R356
(2 pcs)
Helical gear 15
Helical gear 15
Helical gear 35
Helical gear 35
Ball bearing 6900ZZ
Ball bearing
6900ZZ
Gear shaft
Tapping screw 4x18 (8 pcs)
Handle L
1) Remove Handle L from Handle R by unscrewing eight 4x18 Tapping screws. Remove the assembly of Gear housing
and Motor section from Handle R by unscrewing three 4x35 Tapping screws. (Fig. 16)
2) Remove Gear unit from Handle R. (Fig. 17)
3) Remove Ball bearing 604ZZ from Gear unit by following the steps below:
1. Move Ball bearing 604ZZ so as to provide a space between Helical gear 35 and
Ball bearing 604ZZ for inserting 1R356. (Fig. 18)
2. Insert 1R356 (2 pcs) into the space provided in the previous step.
Apply 1R278 to the end face of Gear shaft. By pressing 1R278 using arbor press,
Ball bearing 604ZZ can be removed from Gear unit. (Fig. 19)
4) Set Gear unit on 1R037 with the side of Helical gear 15 up. Apply 1R281 to the
end face of Gear shaft. By pressing 1R281 using arbor press, Gear shaft can be
removed form Gear unit. (Fig. 20)
Handle R
1R281
1R037
Handle R, viewed from
Motor section side
Gear unit
Tapping screw 4x35 (3 pcs)
Gear housing
Motor section
Fig. 16
Fig. 17
Fig. 18 Fig. 19 Fig. 20
Ball bearing 604ZZ
Ball bearing 604ZZ
[3] DISASSEMBLY/ASSEMBLY
[3] -3. Gear Unit (that engages with Armature)
1R269
DISASSEMBLING

P 8 /13
Repair
[3] DISASSEMBLY/ASSEMBLY
[3] -3. Gear Unit (that engages with Armature) (cont.)
1R032
Arbor press
1R028
1) Assemble Helical gear 35 to Gear shaft by following the steps below (Fig. 21):
1. Put Gear shaft on 1R032 with the smaller diameter end of Gear shaft in the center hole of 1R032.
2. Insert Helical gear 35 through Gear shaft.
3. Apply 1R028 to Helical gear 35.
4. Press down 1R028 with arbor press.
2) Assemble Ball bearing 6900ZZ to Gear shaft by following the steps below (Fig. 22):
1. Put the unit you have assembled in the step 1) on 1R032.
2. Insert Ball bearing 6900ZZ through Gear shaft.
3. Apply 1R027 to Ball bearing 6900ZZ.
4. Press down 1R027 with arbor press.
3) Assemble Helical gear 15 to Gear shaft by following the steps below (Fig. 23):
1. Put the unit you have assembled in the step 2) on 1R032.
2. Insert Helical gear 15 through Gear shaft.
3. Apply 1R027 to Helical gear 15.
4. Press down 1R027 with arbor press.
4) Assemble Ball bearing 604ZZ to Gear shaft by following the steps below (Fig. 24):
1. Put the unit you have assembled in the step 3) on Ball bearing 604ZZ.
2. Press down the unit with arbor press.
Helical gear 35
Gear shaft
Note: Be sure to press down 1R028
until it stops so that Helical gear 35
contacts the flanged portion of Gear
shaft.
Note: Be sure to press down 1R027
until it stops so that Ball bearing
6900ZZ contacts the raised center of
Helical gear 35.
Note: Be sure to press down 1R027
until it stops so that Helical gear 15
contacts the stepped portion of Gear
shaft.
Arbor press
Helical gear 35
flanged portion
of Gear shaft
1R032
1R027
Helical gear 35
Ball Bearing
6900ZZ
raised center of
Helical gear 35
Ball Bearing
6900ZZ
Helical gear 15
stepped portion
of Helical gear 35
Arbor press
1R032
1R027
Helical gear 35
Ball Bearing
6900ZZ
Helical gear 15
Ball bearing
604ZZ
Completion of Gear unit
Helical gear 15
Helical gear 35
Ball bearing 6900ZZ
Ball bearing 604ZZ
Fig. 21 Fig. 22 Fig. 23
Fig. 24
ASSEMBLING
Arbor press

P 9 /13
[3] DISASSEMBLY/ASSEMBLY
[3] -4. Armature
1) Remove Motor section and Gear housing from Handle R as illustrated in Fig. 16 on page 7.
2) Remove Carbon brush then Gear housing and Shaft lock. (Fig. 25)
3) Separate Housing R from Housing L by unscrewing four 4x18 Tapping screws.
Take out Motor assembly consisting of Armature, Yoke unit and End bell complete. (Fig. 26)
4) Pull off Armature from Endbell complete throughYoke unit. (Fig. 27)
Fig. 25 Fig. 26 Fig. 27
Brush holder cap
Carbon brush
Gear housing
Shaft lock
Compression
spring 6
Tapping screw 4x18 (4 pcs)
Housing R
Motor assembly
Housing L
Armature
Yoke unit
Endbell
complete
ASSEMBLING
DISASSEMBLING
Your fingers can be pinched
and injured.
[Wrong][Correct] [Wrong][Correct]
Fig. 28 Fig. 29
1) Put Armature through Yoke unit.
Note 1. Yoke unit is not reversible when assembled to Armature. Be sure to assemble so that the notch in Yoke unit is
positioned on the drive-end of Armature as illustrated to left in Fig. 28. If assembled wrong, Motor assembly cannot
be assembled to Housing L.
Note 2. Because Armature is pulled strongly towards Yoke unit by the magent force of Yoke unit;
1. Be sure to hold the gear portion of Armature as illustrated to left in Fig. 29. Do not hold the Armature core
as illustrated to right or your fingers will be pinched between Yoke unit and the fan of Armature.
2. Be careful not to damage the copper wire of Armature.
notch
notch
Repair

P 10/13
[3] DISASSEMBLY/ASSEMBLY
[3] -4. Armature (cont.)
[3] -5. Lock Off Lever and Switch Lever
2) Install Endbell complete on the commutator end of Armature. (Fig. 30)
3) Assemble Motor assembly (consisting of Armature, Yoke unit and Endbell complete) to Housing L. (Fig. 31)
4) Do the reverse of disassembling steps. (Figs. 25 and 26)
Note: Make sure that Shaft lock is set in place before assembling Gear housing to Motor section.
Fit the two ribs on the inside surface
of Housing L in the notch in Yoke unit
when installing Motor assembly to
Housing L.
notch
Yoke unit
Fig. 30 Fig. 31
Fig. 32
Housing L
Lock off lever
Switch lever Switch lever
Compression spring 4
Assemble Lock off lever and Switch lever to Handle L. (Fig. 32)
Note: The same Compression spring 4 is used for Lock off lever and Switch lever.
Compression spring 4
Handle L
Compression spring 4
Insert Compression spring 4 over the boss
on the back of Lock off lever until it stops.
Insert Compression spring 4 over the boss
on the back of Switch lever until it stops.
Switch
Repair
ASSEMBLING
Brush holder of Endbell
notch
For easy assembling, it is recommended
to align the center line of Brush holder
with that of notch in Yoke unit in this step.
two ribs
Lock off lever

Circuit diagram
P 11/13
Power supply
circuit
Switch
Endbell
complete
Terminal
Independent switch for LED
Connector of
Power supply circuit
Connector of LED
(integral part of
Power supply circuit)
LED circuit
Fig. D-1
Protective tube
Color index of lead wires' sheath
Black
White
Red

P 12/13
Wiring diagram
[Blade case viewed from Handle R side]
Lead wire holder
Protective tube
Fix Protective tube that covers LED lead wires
with Lead wire holder on Blade case.
Pull out LED lead wires from the hole in Blade case
as illustrated below.
Connector
Connector
LED circuit
Fig. D-2
[1] Wiring of LED Lead Wire on Blade Case
Route as illustrated in Figs. D-2,D-3.
Fig. D-3
opening
Handle R
Blade case
[2] Wiring Lead Wires of Endbell Complete in/on Motor Section
through hole
Pull out from this through hole.
Endbell complete
Fig. D-4 Fig. D-5
groove
Housing L Housing R Housing L
1) Route on the inside of Housing L as illustrated in Fig. D-4.
Note: Assemble Housing R to Housing L after completion of wiring on the inside of Housing L.
2) Route on the front of Housing R as illustrated in Fig. D-5.
Note: Assemble Gear housing to Motor section after completion of wiring on the front of Housing R.
Lead wire holder
Fix Lead wires with
these Lead wire holders.
Lead wire holder
through hole
[Motor section viewed from front]
Fix with Lead wire holder.Route through this groove.

P 13/13
Wiring diagram
Fig. D-6
[3] Wiring in Handle
Route Lead wires as illustrated in Fig. D-6.
Power supply circuit
Power supply circuit
Handle R
Switch
Flag connector
Terminal
Flag connector and Terminal
wire connecting portion
Handle R
Assemble Power supply circuit to Handle R
with Lead wire (white) on Handle R side.
Lead wire (white)
Terminal
Pole mark
The Flag connector has to be so connected that
the wire connecting portions are positioned
on the side of pole marks of Terminal.
Fix Lead wires with these Lead wire holders.
Independent switch
for LED
Fix Lead wires with these Lead wire holders.