Makita 3901 User manual

1
ENGLISH (Original instructions)
INSTRUCTION MANUAL
DOUBLE INSULATION
WARNING:
For your personal safety, READ and UNDERSTAND before using.
SAVE THESE INSTRUCTIONS FOR FUTURE REFERENCE.
Plate Joiner
3901
004573

2
ENGLISH (Original instructions)
SPECIFICATIONS
Model 3901
Cutter blade
(Outer dia. x Width x Arbor dia.)
100 x 4 x 22 mm
Blade size
Circular saw blade
(Outer dia. x Arbor dia.) 110 x 20 mm
Cutter blade 20 mm
Max. Cutting depth Circular saw blade 25 mm
No load speed (min-1) 11,000
Overall length 307 mm
Net weight 3.0 kg
Safety class /II
• Due to our continuing programme of research and development, the specifications herein are subject to change without notice.
• Specifications may differ from country to country.
• Weight according to EPTA-Procedure 01/2003
END201-5
Symbols
The following show the symbols used for the equipment.
Be sure that you understand their meaning before use.
･Read instruction manual.
･DOUBLE INSULATION
･Only for EU countries
Do not dispose of electric equipment
together with household waste material!
In observance of European Directive
2002/96/EC on waste electric and
electronic equipment and its
implementation in accordance with
national law, electric equipment that
have reached the end of their life must
be collected separately and returned to
an environmentally compatible
recycling facility.
ENE013-1
Intended use
The tool is intended for cutting crescent shaped slots for
the placement of flat wooden dowels or biscuit by a
plunging action.
ENF002-1
Power supply
The tool should be connected only to a power supply of
the same voltage as indicated on the nameplate, and
can only be operated on single-phase AC supply. They
are double-insulated in accordance with European
Standard and can, therefore, also be used from sockets
without earth wire.
ENG102-3
Noise
The typical A-weighted noise level determined according
to EN60745:
Sound pressure level (LpA) : 87 dB(A)
Sound power level (LWA) : 98 dB(A)
Uncertainty (K) : 3 dB(A)
Wear ear protection
ENG224-2
Vibration
The vibration total value (tri-axial vector sum)
determined according to EN60745:
Work mode : rotation without load
Vibration emission (ah) : 2.5 m/s2or less
Uncertainty (K) : 1.5 m/s2
ENG901-1
• The declared vibration emission value has been
measured in accordance with the standard test
method and may be used for comparing one tool
with another.
• The declared vibration emission value may also be
used in a preliminary assessment of exposure.
WARNING:
• The vibration emission during actual use of the
power tool can differ from the declared emission
value depending on the ways in which the tool is
used.
• Be sure to identify safety measures to protect the
operator that are based on an estimation of
exposure in the actual conditions of use (taking
account of all parts of the operating cycle such as
the times when the tool is switched off and when it
is running idle in addition to the trigger time).

3
ENH101-13
For European countries only
EC Declaration of Conformity
We Makita Corporation as the responsible
manufacturer declare that the following Makita
machine(s):
Designation of Machine:
Plate Joiner
Model No./ Type: 3901
are of series production and
Conforms to the following European Directives:
98/37/EC until 28th December 2009 and then with
2006/42/EC from 29th December 2009
And are manufactured in accordance with the following
standards or standardised documents:
EN60745
The technical documentation is kept by our authorised
representative in Europe who is:
Makita International Europe Ltd,
Michigan, Drive, Tongwell,
Milton Keynes, MK15 8JD, England
30th January 2009
000230
Tomoyasu Kato
Director
Makita Corporation
3-11-8, Sumiyoshi-cho,
Anjo, Aichi, JAPAN
GEA005-3
General Power Tool Safety
Warnings
WARNING Read all safety warnings and all
instructions. Failure to follow the warnings and
instructions may result in electric shock, fire and/or
serious injury.
Save all warnings and
instructions for future reference.
The term "power tool" in the warnings refers to your
mains-operated (corded) power tool or battery-operated
(cordless) power tool.
Work area safety
1. Keep work area clean and well lit. Cluttered or
dark areas invite accidents.
2. Do not operate power tools in explosive
atmospheres, such as in the presence of
flammable liquids, gases or dust. Power tools
create sparks which may ignite the dust or fumes.
3. Keep children and bystanders away while
operating a power tool. Distractions can cause
you to lose control.
Electrical safety
4. Power tool plugs must match the outlet. Never
modify the plug in any way. Do not use any
adapter plugs with earthed (grounded) power
tools. Unmodified plugs and matching outlets will
reduce risk of electric shock.
5. Avoid body contact with earthed or grounded
surfaces such as pipes, radiators, ranges and
refrigerators. There is an increased risk of
electric shock if your body is earthed or grounded.
6. Do not expose power tools to rain or wet
conditions. Water entering a power tool will
increase the risk of electric shock.
7. Do not abuse the cord. Never use the cord for
carrying, pulling or unplugging the power tool.
Keep cord away from heat, oil, sharp edges or
moving parts. Damaged or entangled cords
increase the risk of electric shock.
8. When operating a power tool outdoors, use an
extension cord suitable for outdoor use. Use of
a cord suitable for outdoor use reduces the risk of
electric shock.
9. If operating a power tool in a damp location is
unavoidable, use a residual current device
(RCD) protected supply. Use of an RCD reduces
the risk of electric shock.
10. Use of power supply via a RCD with a rated
residual current of 30mA or less is always
recommended.
Personal safety
11. Stay alert, watch what you are doing and use
common sense when operating a power tool.
Do not use a power tool while you are tired or
under the influence of drugs, alcohol or
medication. A moment of inattention while
operating power tools may result in serious
personal injury.
12. Use personal protective equipment. Always
wear eye protection. Protective equipment such
as dust mask, non-skid safety shoes, hard hat, or
hearing protection used for appropriate conditions
will reduce personal injuries.
13. Prevent unintentional starting. Ensure the
switch is in the off-position before connecting
to power source and/or battery pack, picking
up or carrying the tool. Carrying power tools
with your finger on the switch or energising power
tools that have the switch on invites accidents.
14. Remove any adjusting key or wrench before
turning the power tool on. A wrench or a key left
attached to a rotating part of the power tool may
result in personal injury.

4
15. Do not overreach. Keep proper footing and
balance at all times. This enables better control
of the power tool in unexpected situations.
16. Dress properly. Do not wear loose clothing or
jewellery. Keep your hair, clothing, and gloves
away from moving parts. Loose clothes,
jewellery or long hair can be caught in moving
parts.
17. If devices are provided for the connection of
dust extraction and collection facilities,
ensure these are connected and properly used.
Use of dust collection can reduce dust-related
hazards.
Power tool use and care
18. Do not force the power tool. Use the correct
power tool for your application. The correct
power tool will do the job better and safer at the
rate for which it was designed.
19. Do not use the power tool if the switch does
not turn it on and off. Any power tool that cannot
be controlled with the switch is dangerous and
must be repaired.
20. Disconnect the plug from the power source
and/or the battery pack from the power tool
before making any adjustments, changing
accessories, or storing power tools. Such
preventive safety measures reduce the risk of
starting the power tool accidentally.
21. Store idle power tools out of the reach of
children and do not allow persons unfamiliar
with the power tool or these instructions to
operate the power tool. Power tools are
dangerous in the hands of untrained users.
22. Maintain power tools. Check for misalignment
or binding of moving parts, breakage of parts
and any other condition that may affect the
power tool’s operation. If damaged, have the
power tool repaired before use. Many accidents
are caused by poorly maintained power tools.
23. Keep cutting tools sharp and clean. Properly
maintained cutting tools with sharp cutting edges
are less likely to bind and are easier to control.
24. Use the power tool, accessories and tool bits
etc. in accordance with these instructions,
taking into account the working conditions
and the work to be performed. Use of the power
tool for operations different from those intended
could result in a hazardous situation.
Service
25. Have your power tool serviced by a qualified
repair person using only identical replacement
parts. This will ensure that the safety of the power
tool is maintained.
26. Follow instruction for lubricating and
changing accessories.
27. Keep handles dry, clean and free from oil and
grease.
GEB020-2
PLATE JOINER SAFETY
WARNINGS
1. Blades must be rated for at least the speed
recommended on the tool. Blades running over
rated speed can fly apart and cause injury.
2. Always use the guard. The guard protects the
operator from broken blade fragments and
unintentional contact with the blade.
3. Hold power tools by insulated gripping
surfaces when performing an operation where
the cutting tool may contact hidden wiring or
its own cord. Contact with a "live" wire will make
exposed metal parts of the tool "live" and could
give the operator an electric shock.
4. Use only the blades specified for this tool.
5. Never operate the tool with the blade locked in
exposed position or without the blade cover
secured properly in place.
6. Make sure that the blade slides smoothly
before operation.
7. Check the blades carefully for cracks or
damage before operation. Replace cracked or
damaged blades immediately.
8. Make sure that the flange fits in the arbor hole
when installing the blade.
9. Inspect for and remove all nails or foreign
matter from the workpieces before operation.
10. Always place the workpieces on a stable
workbench.
11. Secure the workpieces firmly with clamp or
vise.
12. NEVER wear gloves during operation.
13. Hold the tool firmly with both hands.
14. Keep your hands and body away from the
cutting area.
15. Run the tool for a while without the blade
pointing toward anybody. Watch for vibration
or wobbling that could indicate poor
installation or a poorly balanced blade.
16. Never reach your hands underneath the
workpieces while the blade is rotating.
17. Do not leave the tool running unattended.
18. Always be sure that the tool is switched off
and unplugged before making any
adjustments or replacing the blade.
19. Some material contains chemicals which may
be toxic. Take caution to prevent dust
inhalation and skin contact. Follow material
supplier safety data.
20. Do not use blunt or damaged blades.

5
21. Do not use the tool with damaged guards.
SAVE THESE INSTRUCTIONS.
WARNING:
DO NOT let comfort or familiarity with product
(gained from repeated use) replace strict adherence
to safety rules for the subject product. MISUSE or
failure to follow the safety rules stated in this
instruction manual may cause serious personal
injury.
FUNCTIONAL DESCRIPTION
CAUTION:
• Always be sure that the tool is switched off and
unplugged before adjusting or checking function on
the tool.
Adjusting the depth of cut
1
2
3
004574
6 cutting depths can be preset according to the size of
biscuit to be used or if trimming the wall or ceiling panels
as explained later. Rotate the stopper until the pointer
points to the appropriate size marked on the stopper.
Refer to the table below for the correspondence
between the sizes marked on the stopper and the biscuit
size. Fine adjustments to the cutting depth can be made
by turning the adjusting screw after loosening the hex
nut. This may become necessary after the blade has
been resharpened a few times.
Size onstopper0 1020 S D MAX
Biscuitsize 01020 ---
Depth of cut 8 mm 10mm
12.3mm 13mm 14.7 mm 20 mm
006424
Angle guide
1
2
345
004575
2
3
1
4
004576
The angle guide can be moved up and down to adjust
the position of the blade in relation to the top of the
workpiece.
To adjust the angle guide height, loosen the lock lever
down and rotate the knob until the pointer points to the
desired scale graduation marked on the angle guide.
Then tighten the lock lever up to secure the angle guide.
The scale on the angle guide indicates the distance from
the top of the workpiece to the center of the blade
thickness.
Fence
12
3
004577
10 mm (0.4")
10 mm (0.4")
1
2
3
45
004578
1. Lock lever
2. Pointer
3. Angle scale
4. Center of blade
thickness
5. Base
1. Fence
2. Lock lever
3. Angle scale
1. Knob
2. Down
3. Up
4. Center of blade
thickness
1. Lock lever
2. Angle guide
3. Knob
4. Scale
5. Pointer
1. Pointer
2. Stopper
3. Adjusting screw

6
The angle of the fence can be adjusted between 0° and
90° (positive stops at 0°, 45° and 90°). To adjust the
angle, loosen the lock lever and tilt the fence until the
pointer points to the desired graduation on the angle
scale. Then tighten the lock lever to secure the fence.
When the fence is set at 90°, both the distance from the
center of the blade thickness to the fence and the
distance from the center of the blade thickness to the
bottom of the base are 10 mm.
Set plate
1
2
4
3
67
10 mm
(0.4")
10 mm
(0.4")
6 mm
(1/4")
5
004579
1
004580
Use the set plate as shown in the figures when cutting
slots in thin workpieces.
Switch action
1
004581
CAUTION:
• Before plugging in the tool, always check to see
that the slide switch actuates properly and returns
to the "OFF" position when the rear of the slide
switch is depressed.
To start the tool, slide the slide switch toward the "I (ON)"
position. For continuous operation, press the front of the
slide switch to lock it.
To stop the tool, press the rear of the slide switch, then
slide it toward the "O (OFF)" position.
ASSEMBLY
CAUTION:
• Always be sure that the tool is switched off and
unplugged before carrying out any work on the
tool.
Removing or installing the blade
1
2
3
4
5
004582
CAUTION:
• When installing the cutter blade, mount the inner
flange with the side marked "22" facing toward you.
• When installing the circular saw blade, mount the
inner flange with the side marked "22" facing
toward the tool.
To remove the blade, loosen the clamp screw and open
the blade cover. Push the shaft lock and loosen the lock
nut using the lock nut wrench. To install the blade, first
mount the inner flange.
Then mount the blade and the lock nut. Securely tighten
the lock nut using the lock nut wrench. Close the blade
cover and tighten the clamp screw to secure the blade
cover.
CAUTION:
• Use only Makita lock nut wrench provided to
remove or install the blade.
• Always check the depth of cut after replacing the
blade. Reajust it if necessary.
Dust bag
1
23
004583
1. Dust bag
2. Fastener
3. Dust nozzle
1. Lock nut
2. Cutter blade
3. Inner flange
4. Clamp screw
5. Blade cover
1. Slide switch
1. Set plate
1. Lock lever
2. Pointer
3. Angle scale
4. Set plate
5. Thickness of set
plate
6. Center of blade
thickness
7. Base

7
To attach the dust bag, fit it onto the dust nozzle. If the
dust bag becomes an obstacle to your work, turn the
dust nozzle to change the dust bag position.
When the dust bag is about half full, switch off and
unplug the tool. Remove the dust bag from the tool and
pull the bag's fastener out. Empty the dust bag by
tapping it lightly to remove as much of the dust as
possible.
NOTE:
• If you connect a Makita vacuum cleaner to your
plate joiner, more efficient and cleaner operations
can be performed.
OPERATION
How to make joints
Fig. A
004584
Fig. B
004585
Fig. C
004586
Fig. D
004587
Fig. E
004588
To make joints, proceed as follows:
1. Fit the two workpieces together as they will
appear in the finished joint position.
Corner Joint (Fig. A)
T-Butt Joint (Fig. B)
Miter Joint (Fig. C)
Frame Joint (Fig. D)
Edge-To-Edge Joint (Fig. E)
2. Mark the center of the intended biscuit slots on
the workpiece using a pencil.
NOTE:
• The center of slots should be at least 50 mm
from the outer edge of the workpieces.
• Allow 100 mm - 150 mm between slots in
multiple biscuit application.
3. For Corner Joint and T-Butt Joint only
004589
Clamp the vertical workpiece to the workbench.
For Miter Joint only

8
004590
Clamp one workpiece to the workbench with the
mitered edge facing up.
For Frame Joint and Edge-To-Edge Joint only
1
004591
1
004592
Clamp one workpiece to the workbench.
4. Set the depth of cut according to the size of biscuit
to be used. Refer to the table in the "Adjusting the
depth of cut" section.
5. Adjust the angle guide height so that the blade is
centered in the board thickness.
6. Align the center mark on the base with the pencil
line on the workpiece.
004593
7. Switch on the tool and gently push it forward to
extend the blade into the workpiece.
8. Gently return the tool to the original position after
the adjusting screw reaches the stopper.
9. For Corner Joint and T-Butt Joint only
1
004594
1
004595
Clamp the horizontal workpiece to the workbench.
For Miter Joint only
004596
Clamp the other workpiece to the workbench with
the mitered edge facing up.
For Frame Joint and Edge-To-Edge Joint only
1
004597
1. For Frame Joint
1. For T-Butt Joint
1. For Corner Joint
1. For
Edge-To-Edge
Joint
1. For Frame Joint

9
1
004598
Clamp the other workpiece to the workbench.
10. For Corner Joint only
004599
Place the tool on the workpiece so that the blade is
facing down.
For T-Butt Joint only
004600
Remove the angle guide from the tool. Place the
tool on the workpiece so that the blade is facing
down.
11. Repeat the steps 6 - 8 to cut the slots in the
horizontal or the other workpiece.
If you do not need to center the blade in the board
thickness, proceed as follows:
For Corner Joint, Miter Joint, Frame Joint and
Edge-To-Edge Joint only
004601
• Remove the angle guide from the tool. Set the
fence at 90° for Corner Joint, Frame Joint and
Edge-To-Edge Joint or at 45° for Miter Joint.
• Follow steps 1 - 11 excluding steps 5 and 10
described above.
For T-Butt Joint only
004602
004603
• Fit the two workpieces together as they will appear
in the finished joint position.
• Lay the vertical workpiece on the horizontal one.
Clamp both workpieces to the workbench.
• Remove the angle guide from the tool.
• Follow the steps 2, 4, 6, 7, 8 and 11 described
above.
1. For
Edge-To-Edge
Joint

10
How to trim wall or ceiling panels
1
2
3
4
004604
12
004605
First unplug the tool. Open the blade cover and replace
the existing cutter blade with an optional circular saw
blade 110 mm in diameter.
Refer to the "Removing or installing the blade" section
which was described previously. Remove the rubber
facing from the base. Then close and secure the blade
cover. Now the max. depth of cut is 25 mm.
CAUTION:
• Be very careful that the blade has been properly
mounted on the tool spindle between the inner
flange and the lock nut. Be sure to securely tighten
the lock nut.
Set the depth of cut to "MAX". Rest the base on the floor
(when trimming the wall panels) or the wall (when
trimming the ceiling panels). Using the floor or wall as a
guide, trim wall or ceiling panels. Feed in the direction of
the arrow.
1
004606
1
004607
CAUTION:
• Before trimming the panels, check the wall or
ceiling carefully to avoid cutting the electrical wires,
nails or other foreign materials.
• Always reinstall the rubber facing after trimming
the panels. If cutting slots for biscuits without the
rubber facing installed properly on the tool, the tool
might slip unexpectedly on the workpiece, causing
dangerous loss of control of the tool. When
installing the rubber facing, always hook it onto the
inside of the front opening.
MAINTENANCE
CAUTION:
• Always be sure that the tool is switched off and
unplugged before attempting to perform inspection
or maintenance.
Replacing carbon brushes
1
001145
Remove and check the carbon brushes regularly.
Replace when they wear down to the limit mark. Keep
the carbon brushes clean and free to slip in the holders.
Both carbon brushes should be replaced at the same
time. Use only identical carbon brushes.
Use a screwdriver to remove the brush holder caps.
Take out the worn carbon brushes, insert the new ones
and secure the brush holder caps.
1. Limit mark
1. When trimming
the ceiling
panels
1. When trimming
the wall panels
1. Rubber facing
2. Blade cover
1. Lock nut
2. Circular saw
blade
3. Inner flange
4. Blade cover

11
1
2
004608
To maintain product SAFETY and RELIABILITY, repairs,
any other maintenance or adjustment should be
performed by Makita Authorized or Factory Service
Centers, always using Makita replacement parts.
ACCESSORIES
CAUTION:
• These accessories or attachments are
recommended for use with your Makita tool
specified in this manual. The use of any other
accessories or attachments might present a risk of
injury to persons. Only use accessory or
attachment for its stated purpose.
If you need any assistance for more details regarding
these accessories, ask your local Makita Service Center.
• Angle guide
• Dust bag
• Set plate 4
• Lock nut wrench 20
• Cutter blade 100-4
• Cross-cut saw blade
• Combination saw blade
• Carbide-tipped saw blade
1. Brush holder
cap
2. Screwdriver

12
Makita Corporation Anjo, Aichi, Japan
883857E228