Mafell MT55 18M bl Assembly instructions

MT55 18M bl
170701.0122/a
IMPORTANT
Read Before Using
IMPORTANT
Lire avant usage
IMPORTANTE
Leer antes de usar
Operating/Safety Instructions
Consignes d’utilisation/de sécurité
Instrucciones de funcionamiento y seguridad
For English Version
See page 2
Version française
Voir page 30
Versión en español
Ver la página 58

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English
Table of contents
1Signs and symbols ........................................................................................................... 3
1.1 Identification of the device................................................................................................5
2Product specifications ......................................................................................................5
2.1 Technical data .................................................................................................................. 5
2.2 Scope of delivery.............................................................................................................. 6
2.3 Adjustment elements........................................................................................................6
3General safety .................................................................................................................. 7
3.1 Intended use..................................................................................................................... 7
3.2 Foreseeable misuse .........................................................................................................7
3.3 Safety instructions ............................................................................................................ 8
3.4 Specific safety rules .........................................................................................................9
3.5 Safety devices ................................................................................................................12
3.6 Residual risks ................................................................................................................. 13
4Setup / adjustment .........................................................................................................13
4.1 Charging the rechargeable battery................................................................................. 13
4.2 Inserting the rechargeable battery..................................................................................14
4.3 Removing the rechargeable battery ...............................................................................14
4.4 Chip extraction ............................................................................................................... 15
4.5 Saw blade selection .......................................................................................................15
4.6 Changing the saw blade.................................................................................................16
5Operation........................................................................................................................18
5.1 Startup............................................................................................................................18
5.2 Switching on ...................................................................................................................18
5.3 Switching off ...................................................................................................................18
5.4 Cutting depth setting ...................................................................................................... 19
5.5 Setting for bevel cuts......................................................................................................20
5.6 Plunge cuts.....................................................................................................................21
5.7 Sawing along markings ..................................................................................................22
5.8 Sawing with the parallel guide fence .............................................................................. 22
5.9 Working with special accessories................................................................................... 23
6Service and maintenance...............................................................................................26
6.1 Storage........................................................................................................................... 26
6.2 Transport ........................................................................................................................ 26
6.3 Disposal of a rechargeable battery................................................................................. 26
7Troubleshooting..............................................................................................................27
8Optional accessories ...................................................................................................... 29
9Exploded view and spare parts list................................................................................. 29

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1Signs and symbols
These operating instructions contain the following general information signs to guide you, the reader, through
the operating instructions and to provide you with important information.
Sign
Meaning
Important information
This sign highlights user tips and other useful information.
➢
Identifies an intermediate result in a sequence of actions.
✓
Identifies the final result of a sequence of actions.
Tab. 1: General signs and their meanings
Warning icons warn of dangerous points, risks and obstacles.
Icon
Meaning
Warning
This icon can be found at all locations where you can find information regarding your
safety. Non-observance can result in extremely serious injuries.
Warns of danger of electric shock.
Warns of danger caused by dust.
Warns of the danger of cutting.
Warns of the danger of cutting off or severing limbs.
Tab. 2: Warning icons and their meanings

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Mandatory icons are intended to prevent accidents.
Icon
Meaning
Wear eye protection.
Wear dust mask.
Wear hearing protection.
Wear protective gloves.
Tab. 3: Mandatory icons and their meanings
During the operation of the power tool there are always actions to be taken where hazards can occur. These
potentially dangerous actions are preceded by warnings which must be observed.
Classification of the danger level (signal words) of warnings
Warning
Meaning and consequences of non-observance
Imminent danger that will cause serious or fatal injuries.
Potentially dangerous situation that can cause serious or
fatal injuries.
Potentially dangerous situation that can cause minor
injuries.
Tab. 4: Structure of warnings

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1.1 Identification of the device
The icons listed and explained below can be found on the rating plate or on the product.
Symbol
Explanation
Symbol
Explanation
V
Volt
1, 2, 3, ...
I, II, III, ...
Rotational speed setting
A
Ampere
rpm
Revolutions per minute
Hz
Hertz
ø
Saw blade diameter
W
Watt
~
Alternating current
kg
Kilogram (weight)
Protection class II
min
Minutes (time)
Read operating instructions
s
Seconds (time)
Protective goggles
n0
Rated speed at no load
Hearing protection
n
Rated speed at normal load
Dust mask
2Product specifications
2.1 Technical data
Rated voltage
18 V, DC
Saw blade speed at no load
4850 rpm
Cutting depth
0°: 0 - 57 mm [0 - 2.24 in]
30°: 0 to 46 mm [0 to 1.81 in]
45°: 0 - 35 mm [0 - 1.38 in]
Saw unit swivel range
-1° / 0°–48°
Saw blade diameter max/min
162/149 mm [6.38/5.87 in]
Saw blade body thickness
1.2 mm [0.05 in]
Tool cutting width
1.8 mm [0.07 in]
Saw blade mounting hole
20 mm [0.8 in]
Hose connector diameter
35 mm [1.4 in]
Weight with rechargeable battery, without
parallel guide fence
4.5 kg [9.92 lbs]
Dimensions (width x length x height)
250 x 330 x 215 mm [9.84 x 12.99 x 8.46 in]

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2.2 Scope of delivery
Fig. 1: Scope of delivery
Components
A
Plunge cut saw
B
Allen key in a holder on the machine
C
Parallel guide fence
D
Transport box
E
Charger APS M
F
2x rechargeable battery 18M 99 LiHD
G
Position indicator
H
Shavings bag
2.3 Adjustment elements
Fig. 2: Adjustment elements
Adjustment elements on the machine
1
Pointer for cutting depth
2
Cutting depth scale
3
Notch for pre-scoring
4
Switch-on lock
5
Wing screws
6
Operating lever
7
Lever of the rechargeable battery lock
8
Locking lever
9
Pushbutton
10
Swivel slider
11
Setting wheels
12
Tilting segment wing screw
13
Tilting segment scale
14
Swiveling guide fence
15
Slider

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3General safety
Please read all safety instructions and directions. Failure to comply with the safety instructions and
directions can cause electric shock, fire and/or serious injuries. Please retain all safety instructions and
directions for future reference.
3.1 Intended use
The hand-held circular saw is only suitable for ripping and cross cutting of solid wood.
Panel material such as chip board, core board and medium density fiber board can also be processed.
Processing wood fiber insulation materials is also possible.
Use only saw blades that are approved by the manufacturer.
Using the diamond saw blade allows you to cut fiber cement board as well.
Use only the battery packs and the charger approved by the manufacturer.
3.2 Foreseeable misuse
The machine is not intended for any other use than the intended use listed above.
The manufacturer is not liable for any damage resulting from such other use.
To use the machine as intended, comply with the operating, maintenance and repair conditions specified by
MAFELL.
Foreseeable misuse also includes:
- Tampering with, removing and/or bypassing safety devices of any kind.
- Operating the machine without safety devices.
- Non-observance of safety and warning instructions in the operating instructions.
- Removing the safety and warning labels from the machine.
- Operating the machine by unauthorized persons.
- Failure to follow prescribed maintenance and care instructions.
Never use:
- Cracked and/or deformed saw blades.
- Saw blades made of high speed steel (HSS saw blades).
- Blunt saw blades as they impose an excessive load on the motor.
- Saw blades that are not suitable for the no-load speed of the saw blade.

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3.3 Safety instructions
READ ALL INSTRUCTIONS!
Non-observance of the instructions listed below can cause electric shock, fire and/or serious injuries
.
Work area
- Children and adolescents are not allowed to operate this machine.
- Protect the machine and the rechargeable batteries from moisture.
- Do not throw the rechargeable batteries into a fire.
- Never use defective or deformed rechargeable batteries.
- Never try to open the rechargeable batteries.
- Do not touch or short-circuit the contacts of the rechargeable batteries.
- A slightly acidic, flammable liquid can escape from defective rechargeable batteries! Rinse immediately with
plenty of water if battery fluid gets in contact with your skin. If battery fluid gets into your eyes, wash your
eyes with clean water and seek medical attention immediately!
- Remove the batteries from the machine before you adjust, set up, maintain or clean the machine.
- Ensure that the machine is switched off before you insert the rechargeable battery.
- Remove the rechargeable battery from the machine when you put it down, transport it or store it unattended.
- Do not use this machine when you are tired, or under the influence of drugs, alcohol or medicaments. Be
aware of what you are doing. Stay alert and use common sense.
- Keep children and bystanders at a distance while you are operating the machine. Distractions can cause
you to lose control of the machine.
- Use eye protection, dust mask and hearing protection. Appropriate safety equipment, used
under proper conditions, will reduce the risk of injuries.
Instructions for service and maintenance:
- Cleaning the machine regularly, especially the adjustment elements and the guiding devices, is an important
safety factor.
- Ensure that only genuine MAFELL spare parts and accessories are used. Failure to do so will make
warranty claims and the liability of the manufacturer null and void.
- Prepare a periodic maintenance schedule for your machine. When you clean the machine, be careful
not to disassemble any part of the machine. Reassembling the machine bears the risk that internal
wires are routed incorrectly or pinched, or that return springs of the safety device are mounted
incorrectly. Certain cleaning agents, such as gasoline, carbon tetrachloride, ammonia, etc. can damage
plastic parts.

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- Some of the dust produced by sawing, sanding, drilling and other building work contains chemicals
known to cause cancer, birth defects or other reproductive harm. Some examples of these
chemicals are:
- Lead from lead-based paints,
- Crystalline silica from bricks and cement and other masonry products,
- Arsenic and chromium from chemically treated wood.
Your risk from this hazard varies with the frequency at which you perform this type of work. To reduce your
exposure to these chemicals: Work in a well-ventilated area. Work only with approved safety equipment, such
as dust masks that are specially designed to filter out particles of microscopic size.
3.4 Specific safety rules
Sawing method
- Keep your hands away from cutting area and saw blade. Hold the auxiliary handle or the motor
housing with your second hand. If both hands hold the saw, they cannot be injured by the saw blade.
Fig. 3: Incorrect sawing vs. correct sawing
- Do not reach underneath the workpiece. Below the workpiece, the guard cannot protect you from the saw
blade.
- Adjust the cutting depth to the thickness of the workpiece. Less than a full tooth height should be
visible below the workpiece.
- Never hold the workpiece in your hands or across your leg while you are cutting it. Secure the
workpiece on a stable support. It is important to secure the workpiece safely. This minimizes the risk of
body contact, jamming of the saw blade or loss of control over the machine.
- Hold the machine by the insulated grip surfaces when you perform work that involves a risk of the
tool hitting hidden power lines. Contact with a live line also energizes the metallic parts of the machine,
causing an electric shock.
- Always use a fence or straight edge guide for ripping. This improves the cutting accuracy and reduces
the possibility of the saw blade jamming.
- Always use saw blades of the correct size and with a suitable arbor hole (e.g. diamond-shaped or
round). Saw blades that do not match the mounting parts of the saw will run out of true, resulting in a loss of
control.

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- Never use damaged or wrong saw blade washers or bolts. The saw blade washers and bolts are
designed specifically for your saw, for optimal performance and operational safety.
Kickback - causes and related safety instructions
- Kickback is the sudden reaction resulting from a pinched, jammed, or misaligned saw blade that causes an
uncontrolled saw to lift off and move out of the workpiece toward the operator.
- If the saw blade is pinched or jammed in the closing kerf, it will stall and the motor power will kick the saw
back toward the operator.
- If the saw blade is twisted or misaligned in the saw cut, the teeth of the rear edge of the saw blade can get
pinched in the wood surface, causing the saw blade to move out of the kerf and the saw to jump back
toward the operator.
Fig. 4: Kickback of the machine
Kickback is the result of incorrect or improper use of the saw. It can be prevented by taking appropriate
precautions, as described below.
- Hold the saw firmly with both hands. Position your arms such that you can withstand kickback
forces. Be sure that you are always positioned such that the saw blade is at the side of your body,
never in line with it. In the event of a kickback, the circular saw can jump backward. However, the operator
can take appropriate precautions to control the kickback forces.
- If the saw blade jams or when you stop working, switch off the saw and hold it steady in the material
until the saw blade is stopped. Never try to remove the saw from the workpiece or pull it backwards
as long as the saw blade is moving. This can cause a kickback. Determine and eliminate the cause of
jamming of the saw blade.
- To restart a saw that sits in the workpiece, center the saw blade in the kerf and ensure that the saw
teeth are not jammed in the workpiece. A jammed saw blade can move out of the workpiece or cause a
kickback when the saw is restarted.

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- Support large panels to reduce the risk of a kickback from a jammed saw blade. Large panels tend to
sag under their own weight. Panels must be supported on both sides: near the kerf and at the edge.
Fig. 5: Incorrect support vs. correct support
- Never use blunt or damaged saw blades. The kerf produced by a saw blade with blunt or incorrectly
aligned teeth is too narrow, causing increased friction, jamming of the saw blade and kickback.
- Prior to starting sawing, tighten the cutting depth and cutting angle settings. If the settings change
during the sawing process, there is a risk of a jamming saw blade and kickback.
- Be particularly careful when sawing into existing walls or other concealed areas. The saw blade can
jam and cause kickback when cutting into hidden objects.
Function of the guard
- Before each use, check to ensure that the saw blade can be moved downward out of the protective
hood after the switch-on lock has been actuated, and that it returns to its fully retracted position and
engages there when the load is released. The guard can be bent if the saw drops to the ground. Ensure
that the saw blade moves freely and does not get in contact with the guard or other parts at all cutting
angles and cutting depths.
- Check the function of the spring for the guard. Have the saw serviced before use if guard and/or
spring do not function properly. Damaged parts, sticky deposits or accumulations of chips delay the
operation of the guard.
- Never put the saw down on the workbench or the ground when the saw blade is not fully retracted
into the guard. An unprotected coasting saw blade will move the saw in the opposite direction of the cut
and cut whatever is in its path. Be aware of the coasting time of the saw blade.
RETAIN THESE INSTRUCTIONS!

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3.5 Safety devices
Danger
Risk of injury from missing safety devices
These devices are necessary for the safe operation of the machine. They must
not be removed or rendered ineffective.
➢Check the proper functioning of the safety devices before you start
operating the machine.
➢Never use the machine with missing or ineffective safety devices.
The machine is equipped with the following safety devices:
Safety device
Type of check
Fixed guard
Visual check for damage
Functional check (pushing the saw blade out to full
cutting depth and jerk-free abrupt return to the upper
end position and engaging in this position).
Large base plate
Visual check for damage and deformation
Handles
Visual check for damage
Switching device and brake
Functional check (braking time must not be longer
than 7 seconds)
Hose connector
Visual check for damage and obstruction
If the safety devices are damaged or not functioning properly, follow the instructions in the chapter
Troubleshooting. For other malfunctions, please contact your dealer or MAFELL Customer Service directly.

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3.6 Residual risks
Warning
Risk of injury when working with the machine
Even when the machine is used as intended and in compliance with the safety
regulations, there are still residual risks caused by the intended use, which can
have consequences for your health.
➢Observe the safety instructions and information in these instructions.
➢Always be extremely careful and cautious when you work with the machine.
The existing residual risks include:
- Contact with the saw blade in the area of the start-up opening below the base plate.
- Contact with the part of the saw blade that protrudes below the workpiece during the cutting process.
- Contact with rotating parts from the side: Saw blade, clamping flange and flange bolt.
- Kickback of the machine when jammed in the workpiece.
- Breakage and ejection of the saw blade or parts of the saw blade.
- Accidental switch-on when the rechargeable battery is not removed.
- Impaired hearing when working without hearing protection for long periods of time.
- Emission of harmful wood dusts during longer operation without extraction.
4Setup / adjustment
4.1 Charging the rechargeable battery
Rechargeable battery and charger are matched to each other. Use only the MAFELL chargers for charging.
First, charge the rechargeable battery when you use a new machine.
The charging process is described in the "Charger APS M" instructions supplied.
A significantly shortened operating time after charging indicates that the rechargeable battery is exhausted and
needs to be replaced.
The rechargeable battery is equipped with a temperature monitor. This ensures that the rechargeable battery is
only charged in the optimal temperature range between 0 °C (32 °F) and 50 °C (122 °F). This ensures a long
battery life.

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Warning
Risk of fire and explosion due to overheating or moisture
High temperatures and moisture can cause short-circuits in the rechargeable
battery. There is a risk of fire and explosion.
➢Protect the rechargeable battery from heat, fire and moisture.
➢Do not expose the rechargeable battery to temperatures above 50 °C (122
°F).
➢Store the rechargeable battery at a temperature between 10 °C (50 °F)
and 30 °C (86 °F).
➢Allow the rechargeable battery to cool down before you start charging it.
4.2 Inserting the rechargeable battery
Prior to inserting the battery, check to ensure that the rated voltage of the rechargeable battery matches the
specification on the machine.
Use the following procedure to insert the
rechargeable battery into the machine:
1. Insert the charged rechargeable battery into the
battery guide until you feel that it locks into
place.
2. Check to ensure that the battery is firmly seated
in the machine.
✓The rechargeable battery is inserted in the
machine.
Fig. 6: Inserting the rechargeable battery into the machine
4.3 Removing the rechargeable battery
Use the following procedure to remove the
rechargeable battery:
1. Press and hold the lever (7) of the battery lock.
2. Pull the rechargeable battery out of the guide.
✓The rechargeable battery is removed.
Fig. 7: Removing the rechargeable battery

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4.4 Chip extraction
Caution
Health hazards from wood dust
The dusts produced during work can be inhaled and can cause health damage.
➢Harmful dust must be extracted with a HEPA 13 dust extractor.
➢Wear a dust mask during work.
For all work that produces a significant amount of dust, connect the machine to a suitable external extraction
device. The air velocity must be at least 20 m/s [65 ft/sec].
The inner diameter of the hose connector is 35 mm [1.4 in].
For short-time work that generates a small amount of dust, you can use the shavings bag provided as a self-
suction device.
4.5 Saw blade selection
To achieve good cutting quality, use a sharp tool and select a tool from the following list that is appropriate for
material and application:
Cutting softwood and hardwood across and along the grain direction:
- Carbide circular saw blade Ø 160 x 1.8 x 20 mm, 32 teeth [Ø 6.30 x 0.07 x 0.79 in]
Cutting softwood and hardwood especially along the grain direction:
- Carbide circular saw blade Ø 160 x 1.8 x 20 mm, 16 teeth [Ø 6.30 x 0.07 x 0.79 in]
Cutting softwood and hardwood especially across the grain direction:
- Carbide circular saw blade Ø 162 x 1.8 x 20 mm, 48 teeth [Ø 6.38 x 0.07 x 0.79 in]
Cutting softwood and hardwood especially across the grain direction "fine cuts":
- Carbide circular saw blade Ø 160 x 1.8 x 20 mm, 56 teeth [Ø 6.30 x 0.07 x 0.79 in]
Cutting wood fiber insulation material:
- Carbide circular saw blade Ø 160 x 1.8 x 20 mm, 32 teeth [Ø 6.30 x 0.07 x 0.79 in]
Cutting plastic material (styrofoam):
- Carbide circular saw blade Ø 160 x 1.8 x 20 mm, 16 teeth [Ø 6.30 x 0.07 x 0.79 in]
Cutting fiber cement board:
- Diamond saw blade Ø 160 x 3.0 x 20 mm, 4 teeth [Ø 6.30 x 0.12 x 0.79 in]

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4.6 Changing the saw blade
Caution
Risk of injury from the sharp saw blade
The saw blade is sharp. You can hurt yourself when you change the saw blade.
➢Wear protective gloves when you change the saw blade.
➢Be careful when you change the saw blade.
Use the following procedure to change the saw
blade:
1. Pull the rechargeable battery out of the
machine.
2. Put the machine on a flat surface.
3. Press and hold the pushbutton (9).
4. Pull the locking lever (8) upwards.
➢The guard cover is unlocked and can be
opened sideways. Saw shaft and
operating lever are locked automatically.
Fig. 8: Unlocking the guard cover
5. Open the guard cover sideways.
Fig. 9: Opening the guard cover

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6. Using the Allen key (B), turn the flange screw
(16) counterclockwise to loosen it.
7. Remove the flange screw (16) and the front
clamping flange (17).
8. Remove the old saw blade.
➢Clamping flanges must be free of adhering
parts!
➢The new saw blade can now be installed.
Fig. 10: Removing the old saw blade
9. Position the new saw blade (18) on the rear
flange (20).
➢Ensure that the direction of rotation is
correct when you install the saw blade.
The saw teeth or the arrow on the saw
blade (18) must point in the direction of the
arrow (19) on the machine.
10. Fit clamping flange (17) and flange screw (16).
11. Using the Allen key (B), turn the flange screw
(16) clockwise to tighten it.
➢The saw blade is secured.
Fig. 11: Replacing the saw blade
12. Close the guard cover.
13. To do this, press the locking lever (8) down.
➢The mechanism that locks the saw shaft is
activated.
➢The operating lever is unlocked.
✓The saw blade is changed.
Fig. 12: Closing the guard cover

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5Operation
5.1 Startup
These operating instructions must be brought to the attention of all persons entrusted with the operation of the
machine, with particular emphasis on the chapter "Safety instructions".
5.2 Switching on
Use the following procedure to switch on the
machine:
1. Press the switch-on lock (4) forward to unlock.
2. With the switch-on lock depressed, actuate and
hold the operating lever (6).
3. Release the switch-on lock (4).
✓The machine is switched on
Fig. 13: Switching the machine on
Since the switch is not latching, the machine runs only as long as the operating lever is
pressed. Due to the motor concept used here, the machine stops very quickly when it is
switched off. (Motor brake)
5.3 Switching off
Use the following procedure to switch off the
machine:
1. Release the operating lever (6).
➢The integrated automatic brake limits the
coasting time of the saw blade to approx. 2
seconds.
➢The switch-on lock is activated
automatically and secures the hand-held
circular saw against being switched on
inadvertently.
✓The machine is switched off.
Fig. 14: Switching the machine off

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5.4 Cutting depth setting
The cutting depth can be set continuously in a range between 0 and 57 mm [0 to 2.24 in].
Use the following procedure to set the cutting
depth:
1. Rotate the pointer (1) depending on whether or
not you are working with a guide rail (optional
accessory).
➢Top position = with guide rail
➢Bottom position = without guide rail
The cutting depth is reduced by 6 mm [0.24 in] when
a guide rail is used.
Fig. 15: Cutting depth pointer position
2. Use the pointer (1) to set the cutting depth.
➢The cutting depth is indicated on the scale
(2) on the cover. The scale has a 1-mm
graduation.
➢To readjust the cutting depth setting, you
can use the Allen key (B) to turn the fillister
head screw (21). One revolution
corresponds to a cutting depth change of 1
mm [0.04 in].
✓The cutting depth is set.
Fig. 16: Setting the cutting depth
For separating cuts, always set the
cutting depth to approx. 2 ... 5 mm
[0.08 ... 0.2 in] more than the
material thickness you want to cut.

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5.5 Setting for bevel cuts
For bevel cuts, the saw unit can be set to any angle from 0° to 45°.
Use the following procedure to set the saw unit
for bevel cuts:
1. For tilting, put down and support the machine so
that the saw unit can be tilted.
2. Loosen the wing screw (12).
3. Use the scale (13) on the tilting segment to set
the angle.
4. Tighten the wing screw (12).
✓The saw unit is set to the desired angle for
the bevel cut.
Fig. 17: Setting the saw unit for bevel cuts
In addition, the machine can be swiveled to -1° or 48°.
Use the following procedure to set the saw unit to
-1°:
1. Pull the slider (10) backward in the direction of
the arrow and hold it in place.
2. Set the machine to an angle of -1°.
✓The saw unit is set to -1°.
Fig. 18: Setting the saw unit to -1°
Use the following procedure to set the saw unit to
48°:
1. Press down the guide fence (14) on the side of
the machine and hold it in place.
2. Set the machine to an angle of 48°.
✓The saw unit is set to 48°.
Fig. 19: Setting the saw unit to 48°
For any angle of bevel cutting, the slider (15) can be moved such that it rests on the workpiece, minimizing
dust leakage during the sawing process.