Makita 3901 User manual

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

2
SPECIFICATIONS
• Due to our continuing programme of research and development, the specifications herein are subject to change
without notice.
• Note: Specifications may differ from country to country.
SYMBOLS END201-2
The following show the symbols used for the tool. 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 mate-
rial!
In observance of European Directive
2002/96/EC on waste electric and
electronic equipment and its imple-
mentation in accordance with
national law, electric equipment that
have reached the end of their life
must be collected separately and
returned to an environmentally com-
patible recycling facility.
Intended use
The tool is intended for cutting crescent shaped slots for
the placement of flat wooden dowels or biscuit by a
plunging action.
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.
For European countries only
Noise and Vibration
The typical A-weighted noise levels are
sound pressure level: 86 dB (A)
sound power level: 99 dB (A)
– Wear ear protection. –
The typical weighted root mean square acceleration
value is not more than 2.5 m/s2.
EC-DECLARATION OF CONFORMITY
We declare under our sole responsibility that this prod-
uct is in compliance with the following standards of
standardized documents, HD400, EN50144, EN55014,
EN61000 in accordance with Council Directives, 73/23/
EEC, 89/336/EEC, 98/37/EC.
Yasuhiko Kanzaki CE 2003
Director
MAKITA INTERNATIONAL EUROPE LTD.
Michigan Drive, Tongwell, Milton Keynes, Bucks MK15
8JD, ENGLAND
Model 3901
Blade size
Cutter blade
(Outer dia. x Width x Arbor dia.) 100 x 4 x 22 mm
Circular saw blade
(Outer dia. x Arbor dia.) 110 x 20 mm
Max. Cutting depth
Cutter blade 20 mm
Circular saw blade 25 mm
No load speed (min-1)11,000
Overall length 307 mm
Net weight 2.8 kg
Safety class /II

3
SAFETY INSTRUCTIONS ENA001-2
WARNING:
When using electric tools, basic safety precautions, including the following,
should always be followed to reduce the risk of fire, electric shock and
personal injury. Read all these instructions before operating this product
and save these instructions.
For safe operations:
1. Keep work area clean.
Cluttered areas and benches invite injuries.
2. Consider work area environment.
Do not expose power tools to rain. Do not use
power tools in damp or wet locations. Keep work
area well lit. Do not use power tools where there is
risk to cause fire or explosion.
3. Guard against electric shock.
Avoid body contact with earthed or grounded sur-
faces (e.g. pipes, radiators, ranges, refrigerators).
4. Keep children away.
Do not let visitors touch the tool or extension cord.
All visitors should be kept away from work area.
5. Store idle tools.
When not in use, tools should be stored in a dry,
high or locked up place, out of reach of children.
6. Do not force the tool.
It will do the job better and safer at the rate for which
it was intended.
7. Use the right tool.
Do not force small tools or attachments to do the job
of a heavy duty tool. Do not use tools for purposes
not intended; for example, do not use circular saws
to cut tree limbs or logs.
8. Dress properly.
Do not wear loose clothing or jewellery, they can be
caught in moving parts. Rubber gloves and non-skid
footwear are recommended when working outdoors.
Wear protecting hair covering to contain long hair.
9. Use safety glasses and hearing protection.
Also use face or dust mask if the cutting operation is
dusty.
10. Connect dust extraction equipment.
If devices are provided for the connection of dust
extraction and collection facilities ensure these are
connected and properly used.
11. Do not abuse the cord.
Never carry the tool by the cord or yank it to discon-
nect it from the socket. Keep the cord away from
heat, oil and sharp edges.
12. Secure work.
Use clamps or a vice to hold the work. It is safer
than using your hand and it frees both hands to
operate the tool.
13. Do not overreach.
Keep proper footing and balance at all times.
14. Maintain tools with care.
Keep cutting tools sharp and clean for better and
safer performance. Follow instructions for lubrica-
tion and changing accessories. Inspect tool cord
periodically and if damaged have it repaired by an
authorized service facility. Inspect extension cords
periodically and replace, if damaged. Keep handles
dry, clean and free from oil and grease.
15. Disconnect tools.
When not in use, before servicing and when chang-
ing accessories such as blades, bits and cutters.
16. Remove adjusting keys and wrenches.
Form the habit of checking to see that keys and
adjusting wrenches are removed from the tool
before turning it on.
17. Avoid unintentional starting.
Do not carry a plugged-in tool with a finger on the
switch. Ensure switch is off when plugging in.
18. Use outdoor extension leads.
When tool is used outdoors, use only extension
cords intended for outdoor use.
19. Stay alert.
Watch what you are doing. Use common sense. Do
not operate tool when you are tired.
20. Check damaged parts.
Before further use of the tool, a guard or other part
that is damaged should be carefully checked to
determine that it will operate properly and perform
its intended function. Check for alignment of moving
parts, free running of moving parts, breakage of
parts, mounting and any other conditions that may
affect its operation. A guard or other part that is
damaged should be properly repaired or replaced
by an authorized service center unless otherwise
indicated in this instruction manual. Have defective
switches replaced by an authorized service facility.
Do not use the tool if the switch does not turn it on
and off.
21. Warning.
The use of any accessory or attachment, other than
those recommended in this instruction manual or
the catalog, may present a risk of personal injury.
22. Have your tool repaired by a qualified person.
This electric tool is in accordance with the relevant
safety requirements. Repairs should only be carried
out by qualified persons using original spare parts,
otherwise this may result in considerable danger to
the user.

4
ADDITIONAL SAFETY RULES ENB060-2
1. Hold tool by insulated gripping surfaces when
performing an operation where the cutting tool
may contact hidden wiring or its own cord. Con-
tact with a “live”wire will make exposed metal parts
of the tool “live”and shock the operator.
2. Use only the blades specified for this tool.
3. Never operate the tool with the blade locked in
exposed position or without the blade cover
secured properly in place.
4. Make sure that the blade slides smoothly before
operation.
5. Check the blade for cracks or damage before
operation. Replace cracked or damaged blade
immediately.
6. Make sure that the flange fits in the arbor hole
when installing the blade.
7. Inspect for and remove all nails or foreign mat-
ter from the workpieces before operation.
8. Always place the workpieces on a stable work-
bench.
9. Secure the workpieces firmly with clamp or vise.
10. Never wear gloves during operation.
11. Hold the tool firmly with both hands.
12. Keep your hands and body away from the cut-
ting area.
13. Run the tool for a while without the blade point-
ing toward anybody. Watch for vibration or wob-
bling that could indicate poor installation or a
poorly balanced blade.
14. Never reach your hands underneath the work-
pieces while the blade is rotating.
15. Do not leave the tool running unattended.
16. Always be sure that the tool is switched off and
unplugged before making any adjustments or
replacing the blade.
17. Do not use blunt or damaged disk cutters.
18. Do not use the tool with damaged guards.
SAVE THESE INSTRUCTIONS

5
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
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.
C00084
Angle guide
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 work-
piece to the center of the blade thickness.
1. Pointer
2. Stopper
3. Adjusting screw
1
2
3
004574
Size on stopper 0 10 20 S D MAX
Biscuit size 0 10 20 - - -
Depth of cut 8 mm 10 mm 12.3 mm 13 mm 14.7 mm 20 mm
1. Lock lever
2. Angle guide
3. Knob
4. Scale
5. Pointer
1. Knob
2. Down
3. Up
4. Center of blade thickness
1
2
345
004575
2
3
1
4
004576

6
Fence
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.
1. Fence
2. Lock lever
3. Angle scale
1. Lock lever
2. Pointer
3. Angle scale
4. Center of blade thickness
5. Base
12
3
004577
10 mm (0.4”)
10 mm (0.4”)
1
2
3
45
004578

7
Set plate
Use the set plate as shown in the figures when cutting slots in thin workpieces.
Switch action
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 continu-
ous 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.
1. Lock lever
2. Pointer
3. Angle scale
4. Set plate
5. Thickness of set plate
6. Center of blade thickness
7. Base
1. Set plate
1
2
4
3
67
10 mm
(0.4”)
10 mm
(0.4”)
6 mm
(1/4”)
5
004579
1
004580
1. Slide switch
1
004581

8
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
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
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.
1. Lock nut
2. Cutter blade
3. Inner flange
4. Clamp screw
5. Blade cover
1
2
3
4
5
004582
1. Dust bag
2. Fastener
3. Dust nozzle
1
23
004583

9
OPERATION
How to make joints
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.
Fig. A
004584
Fig. B
004585
Fig. C
004586
Fig. D
004587

10
3. For Corner Joint and T-Butt Joint only
Clamp the vertical workpiece to the workbench.
For Miter Joint only
Clamp one workpiece to the workbench with the mitered edge facing up.
For Frame Joint and Edge-To-Edge Joint only
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.
Fig. E
004588
004589
004590
1. For Frame Joint
1. For Edge-To-Edge Joint
1
004591
1
004592

11
6. Align the center mark on the base with the pencil line on the workpiece.
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
Clamp the horizontal workpiece to the workbench.
For Miter Joint only
Clamp the other workpiece to the workbench with the mitered edge fac-
ing up.
004593
1. For Corner Joint
1. For T-Butt Joint
1
004594
1
004595
004596

12
For Frame Joint and Edge-To-Edge Joint only
Clamp the other workpiece to the workbench.
10. For Corner Joint only
Place the tool on the workpiece so that the blade is facing down.
For T-Butt Joint only
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 work-
piece.
If you do not need to center the blade in the board thickness, proceed as fol-
lows:
For Corner Joint, Miter Joint, Frame Joint and Edge-To-Edge Joint only
•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.
1. For Frame Joint
1. For Edge-To-Edge Joint
1
004597
1
004598
004599
004600
004601

13
For T-Butt Joint only
•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.
How to trim wall or ceiling panels
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.
004602
004603
1. Lock nut
2. Circular saw blade
3. Inner flange
4. Blade cover
1. Rubber facing
2. Blade cover
1
2
3
4
004604
12
004605

14
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.
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
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.
To maintain product SAFETY and RELIABILITY, repairs, any other mainte-
nance or adjustment should be performed by Makita Authorized or Factory
Service Centers, always using Makita replacement parts.
1. When trimming the wall panels
1. When trimming the ceiling panels
1
004606
1
004607
1. Limit mark
1
001145
1. Brush holder cap
2. Screwdriver
1
2
004608

15
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

Makita Corporation Anjo, Aichi, Japan
883857B228