Markusson RJ12 User manual

Owner’s manual
1. Original Instruction Manual RJ12 Chain Grinder........................................ 2
2. Original-Gebrauchsanleitung RJ12 Chain Grinder................................... 36
3. Manual original de instrucciones Afiladora para cadenas RJ12............... 70
4. Manuel d’instructions d’origine Affûteuse de chaînes RJ12................... 104
5. Traduzione del manuale di istruzioni RJ12 Chain Grinder..................... 138

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Table of Contents
1 Introduction . . . . . . . . . . . . . . . . . 3
1.1 Important user information . . . . . . . . . . 3
1.2 About this manual. . . . . . . . . . . . . . .3
1.3 Intended use . . . . . . . . . . . . . . . . . 3
1.4 Regulatory information . . . . . . . . . . . . 3
1.5 Nameplate . . . . . . . . . . . . . . . . . . 4
1.6 Recycling information . . . . . . . . . . . . .4
2 Safety. . . . . . . . . . . . . . . . . . . . 5
2.1 Safety notices . . . . . . . . . . . . . . . . .5
2.2 Safety instructions . . . . . . . . . . . . . . 5
2.2.1 Work area safety. . . . . . . . . . . .5
2.2.2 Electrical safety . . . . . . . . . . . . 5
2.2.3 Personal safety . . . . . . . . . . . . 6
2.2.4 Power tool use and care. . . . . . . .6
2.2.5 Service. . . . . . . . . . . . . . . . .7
2.3 Signs and symbols . . . . . . . . . . . . . . 7
3 Product Description. . . . . . . . . . . . . 9
3.1 Product overview . . . . . . . . . . . . . . . 9
3.2 Front view . . . . . . . . . . . . . . . . . . .9
3.3 Back view . . . . . . . . . . . . . . . . . . 10
3.4 Grinding head . . . . . . . . . . . . . . . 11
3.5 Controls . . . . . . . . . . . . . . . . . . . 12
3.6 Chain overview . . . . . . . . . . . . . . . 13
3.7 Technical data. . . . . . . . . . . . . . . . 13
4 Installation . . . . . . . . . . . . . . . . . 14
4.1 Safety during installation . . . . . . . . . . 14
4.2 Site requirements . . . . . . . . . . . . . . 14
4.3 Unpack the machine . . . . . . . . . . . . 14
4.4 Bench-mount the machine . . . . . . . . . 15
4.5 Install and center the grinding wheel . . . . 15
4.6 Test the machine before first use . . . . . . 16
5 Operation . . . . . . . . . . . . . . . . . .17
5.1 Safety during operation . . . . . . . . . . . 17
5.2 Prepare for operation . . . . . . . . . . . . 17
5.2.1 Prepare the grinding wheel . . . . . 17
5.2.2 Set the head-tilt angle . . . . . . . . 18
5.2.3 Set the top-plate angle. . . . . . . . 18
5.2.4 Insert the chain . . . . . . . . . . . 19
5.2.5 Set the chain pusher. . . . . . . . . 19
5.2.6 Set the grinding depth . . . . . . . . 20
© 2022 Markusson Professional Grinders AB - All rights reserved.
5.2.7 Set the cutter top plate to
equal lengths . . . . . . . . . . . . 21
5.2.8 Center the grinding disc . . . . . . . 21
5.2.9 Set the grinding length. . . . . . . . 21
5.2.10 Test the grinding settings . . . . . . 22
5.3 Operate the machine . . . . . . . . . . . . 22
5.4 Depth gauge grinding . . . . . . . . . . . . 24
6 Maintenance and Service. . . . . . . . . .26
6.1 Safety during maintenance . . . . . . . . . 26
6.2 Frequency of maintenance . . . . . . . . . 26
6.3 Change the grinding wheel
and fit the grinding wheel guard . . . . . . 27
6.4 Fasten the chain lock . . . . . . . . . . . . 27
6.5 Check and adjust the wire . . . . . . . . . 28
6.6 Service . . . . . . . . . . . . . . . . . . . 29
7 Troubleshooting. . . . . . . . . . . . . . .30
7.1 Troubleshooting procedure . . . . . . . . . 30
7.2 Sharpening test . . . . . . . . . . . . . . . 30
7.3 Issues . . . . . . . . . . . . . . . . . . . . 31
8 Accessories and Spare Parts. . . . . . . .32
8.1 Ordering information . . . . . . . . . . . . 32
8.2 List of accessories. . . . . . . . . . . . . . 32
8.3 Spare parts . . . . . . . . . . . . . . . . . 33
9 Declaration of conformity . . . . . . . . . .35

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Introduction
1 Introduction
1.1 Important user information
WARNING Before you install, operate or do maintenance on the machine, you must read the safety information
in this manual. Obey the instructions in this manual to prevent injuries or damage to the equipment.
1.2 About this manual
This user manual describes how to safely install, operate, and perform basic maintenance on the product. This
manual also describes the parts of the machine, and it shows different accessories and spare parts that are
available.
1.3 Intended use
The machine must only be used to sharpen the cutting chains used on power saws and forestry machines. It
automatically sharpens the cutting teeth, and depth gauges on 3/8”, 3/8” low profile, 325” and 1/4” pitch chains. The
machine is designed for indoor use only.
Unintended use
The machine must not be used outdoors or in a manner that is not described in this manual.
1.4 Regulatory information
Regulations are given below. A copy of the EC Declaration of conformity is supplied with the machine.
WARNING Before you install, operate or do maintenance on the machine, you must read the safety information
in this manual. Obey the instructions in this manual to prevent injuries or damage to the equipment.
Directive/standard Description
2006/42/EC The Machinery Directive (MD)
2014/35/EU The Low-Voltage Directive (LVD)
2014/30/EU The Electro Magnetic Compatibility Directive (EMC)
EN-ISO:12100:2010 Safety of machinery - Basic components, general principles for design
EN 60204-1:2006 Safety of machinery - Electrical equipment of machines - Part 1: General
requirements
EN 61000-6-3:2007 Emission standard for residential, commercial and light-industrial
environments
EN 55014-1:2017,
EN 55014-2: 2015
Electromagnetic compatibility - Requirements for household
appliances, electric tools and similar apparatus
- Part 1: Emission
- Part 2: Immunity

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Introduction
1.5 Nameplate
This nameplate is placed on the Product.
1.6 Recycling information
This symbol shows that electrical and electronic equipment must not be disposed of as unsorted municipal waste.
It must be collected separately. Recycle according to current local rules and regulations.

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Safety
2 Safety
2.1 Safety notices
This section contains safety information for the power tool. This manual contains WARNINGS, CAUTIONS and
IMPORTANT notes that are applicable for the safe operation of the power tool.
WARNING A warning tells you about conditions that can cause injury or death, if you do not obey the
instructions. Do not continue until all conditions are accepted and engaged.
CAUTION A caution tells you about conditions that can cause damage to equipment, if you do not obey the
instructions. Do not continue until all conditions are accepted and engaged.
IMPORTANT Important or noteworthy information that enables trouble-free and optimal use of the power tool.
2.2 Safety instructions
WARNING Read all safety warnings, instructions, illustrations, and specifications provided with this power tool.
Failure to follow all instructions listed below 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.
WARNING Before you install, operate or do maintenance on the power tool, you must read the safety
information in this manual. Obey the instructions in this manual to prevent injuries or damage to the equipment.
2.2.1 Work area safety
WARNING Keep work area clean and well lit. Cluttered or dark areas invite accidents.
WARNING 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.
WARNING Keep children and bystanders away while operating a power tool. Distractions can cause you to lose
control.
WARNING Put the power tool in a dry indoor area with good lighting. Do not let the power tool become wet or
damp. Do not put the power tool near gas, liquids or other flammable materials.
WARNING The power tool must always be fixed to the floor. Make sure that it is safely attached.
WARNING Attach air hoses and cables with cable clamps, to make sure no one trips over them.
CAUTION Make sure that the floor where the power tool is placed is flat and level. When used with a stand,
attach the stand to the floor with screws.
2.2.2 Electrical safety
WARNING 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.
WARNING 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.
WARNING Do not expose power tools to rain or wet conditions. Water entering a power tool will increase the
risk of electric shock.
WARNING 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.
WARNING 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.
WARNING 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.

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Safety
NOTE The term “residual current device (RCD)” can be replaced by the term “ground fault circuit
interrupter (GFCI)” or “earth leakage circuit breaker (ELCB).”
WARNING Place the power converter where there is as little dust as possible and out of reach of sparks from
the power tool.
CAUTION It is recommended that the tool is always supplied via a residual current device having a rated
residual current of 30 mA or less.
2.2.3 Personal safety
WARNING Stay alert, watch what you are doing and use common sense when operating a power tool. Do not
use a power tool while under the influence of drugs, alcohol or medication. A moment of inattention while operating
power tools may result in serious personal injury.
WARNING Use personal protective equipment. Always wear eye protection. Protective equipment such as a
dust mask, non-skid safety shoes, hard hat or hearing protection used for appropriate conditions will reduce personal
injuries.
WARNING Prevent unintentional starting. Ensure the switch is in the off-position before connecting to a 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.
WARNING 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.
WARNING Do not overreach. Keep proper footing and balance at all times. This enables better control of the
power tool in unexpected situations.
WARNING Dress properly. Do not wear loose clothing or jewellery. Keep your hair and clothing away from
moving parts. Loose clothes, jewellery or long hair can be caught in moving parts.
WARNING 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.
WARNING Do not let familiarity gained from frequent use of tools allow you to become complacent and ignore
tool safety principles. A careless action can cause severe injury within a fraction of a second.
WARNING Always wear safety gloves, protective glasses, and any other personal protective equipment
suitable for your task.
WARNING Be careful around moving parts – risk of squeezing.
WARNING Make sure the machine has stopped moving before you put your hands into the machine.
WARNING Make sure that the power is turned off before you install, operate or do maintenance on the power tool.
WARNING To prevent mistakes when chains are sharpened, it is very important to understand how the chain
grinder works. Read the instructions carefully before operating the power tool.
2.2.4 Power tool use and care
WARNING 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.
WARNING 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.
WARNING Disconnect the plug from the power source and/or remove the battery pack, if detachable, 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.
WARNING Store idle power tools out of the reach of children and do not allow persons unfamiliar with the
power tools or these instructions to operate the power tool. Power tool are dangerous in the hands of untrained
users.

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Safety
WARNING Maintain power tools and accessories. Check for misalignment or binding of moving parts, breakage
of parts and 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.
WARNING Keep cutting tools sharp and clean. Properly maintained cutting tools with sharp cutting edges are
less likely to bind and are easier to control.
WARNING 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.
WARNING Keep handles and grasping surfaces dry, clean and free from oil and grease. Slippery handles and
grasping surfaces do not allow for safe handling and control of the tool in unexpected situations.
WARNING Before a chain is sharpened, make sure that the the grinding disc is not cracked, does not vibrate
or wobble. If the grinding disc is damaged it must be replaced immediately, see chapter 6.3. “Change the grinding
disc and fit the grinding disc guard”. You can also do a simple “ring test” to check for damage; see 4.7, “Installing
the grinding wheel.” If abnormal vibrations occur during operation, immediately stop the machine and check the
condition of the grinding wheel.
WARNING The supply cord can only be replaced by the manufacturer, or approved and trained service
technicians in order to avoid a safety hazard.
WARNING Stop the power tool immediately if it does not work correctly.
CAUTION Only use accessories that are supplied or approved by the manufacturer.
CAUTION If the pitch is not correctly set the chain will be pushed into an incorrect sharpening position. This
may result in a damaged chain.
CAUTION If the metal of a cutting link turns blue during grinding, the speed is set too high and the metal is
overheated. This can cause the metal in the cutting tooth to lose its properties. Replace the damaged cutting link or
sharpen the chain again.
CAUTION Grinding dust can interfere with the power tool’s operation. Clean the power tool daily to remove all
of the grinding dust. Use a vacuum cleaner, brush or similar to clean the power tool.
2.2.5 Service
WARNING 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.
WARNING The user must only perform maintenance that is described in this manual. Only approved and
trained service technicians can service the power tool.
2.3 Signs and symbols
See the table below for information about the signs and symbols on the product.
Sign/Symbol Description
Warning! A warning tells you about conditions that can cause injury or death, if you do not obey the
instructions. Do not continue until all conditions are accepted and engaged.
Risk for cutting injuries. Keep fingers away from the area when the machine is on.
Risk for pinching injuries. Keep fingers away from the area when the machine is on.

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Safety
Sign/Symbol Description
Before you install, operate or do maintenance on the machine, you must read the safety information
in the User manual. Obey the instructions to prevent injuries or damage to the equipment.
Always wear protective gloves when using the machine.
Always wear protective glasses and ear protection when using the machine.

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Product Description
3 Product Description
3.1 Product overview
The RJ12 Chain Grinder is a machine that sharpens chains. The machine can sharpen chains (3/8”, 3/8” Low Profile,
325” and 1/4” pitch) for power saws and forestry machines.
3.2 Front view
A
E
B
G
C
F
D
L
HIJ
K
M
Pos Part Description
AGrinding head Holds the grinding wheel in its correct position.
BGrinding depth knob Sets the grinding depth for the gullets.
CHead-tilt angle scale Shows the head-tilt angle on a scale from 50-90°.
Default: 60°.
DChain pusher adjustment knob Sets the grinding length.
EPitch adjustment wing. Adjusts the pitch.
FPower supply cable Supplies electricity to the machine.
GControl panel The controls starts and stops the different functions of the machine.
See section 3.6, “Controls” for further information.
HChain pusher Advances the chain through the vise
IChain vise Positions the chain as it moves in the machine.
JTop-plate angle knob Sets the top-plate angle, 0-35°. Default 30°.
KLeft-right alignment screw Sets the right and left cutters to equal length.
LGrinding wheel The wheel that sharpens the chain.
MGrinding wheel centering knob Centers the grinding wheel above the chain.

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Product Description
3.3 Back view
N
O
R
QP
Pos Part Description
NGrinding head cover and grinding
wheel guard.
Protects the grinding head and grinding wheel; it also protects the
user from sparks during grinding.
OTop-plate angle scale Shows the top-plate angle on a scale from 0-35°. Default: 30°. It is
set using the top-plate angle screw.
PWire Controls the vertical movement of the grinding head. ets the head-
tilt angle on the head-tilt angle scale.
QWire adjustment knobs Adjusts the wire that controls the vertical movement of the grinding
head.
RHead-tilt angle nut Sets the head-tilt angle on the head-tilt angle scale.

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Product Description
3.4 Grinding head
The grinding wheel on the grinding head sharpens the chains. The type of wheel, the top-plate angles, the settings of
the grinding head, and the profiling of the grinding wheel all determine how the chain is sharpened.
B
C
A
D
Pos Part Description
AGrinding wheel Grinds the chain.
BGrinding wheel nut Keeps the grinding wheel in place.
CGrinding wheel guard Protects the user and grinding wheel when the chain is sharpened.
DAttachment knobs Keep the grinding wheel guard in place.

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Product Description
3.5 Controls
Pos Part Description
AChain pusher switch ON: starts the chain feed, so that the chain moves in a forward
direction. OFF: Stops the chain feed.
BStop button
Shuts off the power and stops the machine. The stop button
is used to turn off the machine after operation and to do an
emergency shut-down.
CGrinding wheel motor switch Starts the grinding motor.
DPower button Turns on the machine.
A
B
C
D

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Product Description
3.6 Chain overview
This section describes the definitions for the parts of a normal chain.
BC
F
DG
E
A
R L
A
Pos Part Description
ACutters R: Right cutter. L: Left cutter.
BDrive link The lower part of a link. Used to push the chain forward in the
chainsaw, etc.
CTie strap The links separating the cutters.
DCutting tooth The part of the cutter that cuts chain.
EGullet The space between the cutting tooth and the depth gauge.
FRivet hole A hole where the rivet is placed.
GDepth gauge The front part of the cutter.
3.7 Technical data
Parameter Value
Supply voltage 12–15 V DC
Power 90 W
Current 7.5 A
Over-current protection Automatic fuse type ptc
Rotation speed, grinding wheel 2800 rpm
Peripheral speed, grinding wheel 22 m/s
Dimensions, grinding wheel
(for the grinding wheels included in the
delivery)
Outer diameter (OD) × Width (W) × Inner diameter (ID):
• 150 mm x 3.2 mm x 16 mm (5 7/8”x 1/8”x 5/8”)
• 150 mm x 6.4 mm x 16 mm (5 7/8”x 1/4”x 5/8”)
Max dimensions for the machine Length (L) x Width (W) x Height (H):
370 mm x 350 mm x 350 mm
Weight of the machine 9.5 kg
Sound power level LwA(working) 92 dB(A)
Sound pressure level LpA(working) 79 dB(A)

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Installation
4 Installation
4.1 Safety during installation
WARNING Before you install, operate or do maintenance on the machine, you must read the safety information
in this manual. Obey the instructions in this manual to prevent injuries or damage to the equipment.
WARNING Always wear safety gloves, protective glasses, and any other personal protective equipment
suitable for the current work task.
4.2 Site requirements
WARNING Put the machine indoors, in a dry area with good light and a flat and level floor. Do not let the
machine become wet or moist. Do not put the machine near gas, liquids or other materials that can catch fire or
explode.
WARNING The machine must always be fixed to the floor or to a workbench. Make sure that it is safely
attached.
Note: Machines can be set up on a bench or you can use the optional stand. Please note that mounting hardware for
the bench is not supplied with the machine.
4.3 Unpack the machine
Note: For a video demonstration of how to unpack, assemble, install, and operate the machine, visit markusson.se.
1. Unpack the box.
Note: Keep the delivery box and packing materials. Pack the machine in them if it is moved or sent for service.
The box and packing materials will minimize the risk of damage during transportation.
2. Make sure that all parts in the list below are included in the delivery:
• RJ12 Chain Grinder machine
• RJ12 Chain Grinder User manual (this document)
• rectangular profile stone (55 x 15 x 15 mm) and profile template
• toolkit with : hex key, which is used to set the right and left cutters to equal length
Allen wrench (T10), which is used for tightening
feeler gauge (0.05 mm), which is used for adjusting the wire
• grinding wheel guard (mounted)
• 2 types of ceramic grinding wheels
• stop clamp
• battery cable (black and red power cable with battery clamps)
Note: For your convenience, you may also use your own tools to assist the machine’s assembly.
3. Remove all packing materials. Leave only the cable ties and the transportation lock that holds the grinding head
in place.

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Installation
4.4 Bench-mount the machine
Always mount the grinder securely, either to a bench
or to the optional stand.
Bench-mounting offers you flexibility and the ability
to sharpen chains virtually anywhere using a 12V
power source.
WARNING If included, place the power
converter where there is as little dust as possible
and out of reach of sparks from the machine.
Note: The chain weight and the power converter are
optional accessories, see section 8, “Accessories
and Spare Parts”.
4.5 Install and center the grinding wheel
Note: The first step in preparing the grinder for use
is installing and centering the appropriate grinding
wheel.
The grinder comes with two wheel sizes: 3.2 mm,
6.4 mm. The wheels are 150 mm in diameter with
16 mm arbor size. It is critical to select the wheel of
the appropriate thickness for each chain.
The correct wheel size for a particular saw chain can
be found in this manual or at the back of the chain
packaging.
2 mm
WARNING Inspect the grinding wheel and
make sure that it is not cracked or damaged. There
is a simple test (called the “ring test”) that you can
do to check for damage to a grinding wheel. Hold
the grinding wheel up by its center hole. Knock the
edge of the grinding wheel gently with a non-metallic
object (like the plastic handle of a screwdriver). If the
grinding wheel makes a dull, non-metallic noise,
then the wheel could be damaged. DO NOT USE IT.
CRACKED GRINDING WHEELS MUST BE
REPLACED IMMEDIATELY. See also section 6.3,
“Change the grinding wheel and fit the grinding
wheel guard”.
Once the grinding wheel has been verified, you’re
ready to begin the install.

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Installation
4. Next, insert the appropriate wheel onto the
grinding motor and, using moderate pressure
with your hands, secure the wheel attachment
nut to hold the wheel in place.
WARNING Over-tightening the wheel can
cause it to break.
5. Finally, reposition the guard and secure it in
place with the knobs.
WARNING Never start the grinder without
the wheel guards in place.
6. Before using the grinder, you’ll need to check to
ensure the wheel is properly installed.
7. With the power off, gently spin the grinding
wheel and check for wheel wobble.
8. Conduct a final check for proper assembly by
turning on the main power and switching on the
wheel power switch while standing to the side.
Look for vibrations due to wheel oscillation or
other interference.
WARNING Always keep bystanders at a
safe distance from a grinder while in operation.
Note: To get the best performance from your
grinder, ensure the grinding wheel is centered
over the vise. Refer to this user manual or the
provided video for specific instructions.
4.6 Test the machine before first use
1. Make sure that all packing materials are
removed.
2. Make sure that the wires and when used with a
stand, air hoses are correctly connected.
3. Make sure that the machine is securely
mounted.
4. Make sure that the machine is on a level
surface.
5. Perform a sharpening test on the machine to
ensure it functions correctly. See section 7.2,
“Sharpening test”
1. Remove the transportation lock (A) and the
cable ties (B) that hold the grinding head in
place.
AB
2. Remove the grinding wheel guard (C) to
access the wheel attachment nut (B). Turn
the two attachment knobs (D) to remove
the guard.
C
D
B
A
3. Remove the wheel attachment nut from
the grinding motor.

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Operation
1. Press the power button to turn on the machine.
2. Set the grinding wheel switch to ON.
3. Make sure that the grinding wheel does not
vibrate or wobble. If the grinding wheel is
damaged, it must be replaced immediately; see
section 6.3, “Change the grinding wheel and fit
the grinding wheel guard”.
4. Make sure the grinding wheel edges match the
shape of the chain type.
• For ceramic grinding wheels: Use the profile
stone (included in delivery) to shape the
edges on the grinding wheel. Use a
light-sweeping action to shape the edges of
the wheel. Use the provided template to verify
proper radius shape for the specific grinding
wheel being used.
.
5 Operation
5.1 Safety during operation
WARNING Before you install, operate or
do maintenance on the machine, you must read
the safety information in this manual. Obey the
instructions in this manual to prevent injuries or
damage to the equipment.
WARNING Always wear safety gloves,
protective glasses, ear protection, and any other
personal protective equipment suitable for the
current work task.
WARNING The grinding disc can fall down on
your hand and cause injuries. Keep fingers away.
WARNING To prevent mistakes when chains
are sharpened, it is very important to understand
how the grinding machine works. Read the
instructions carefully before the machine is used.
WARNING The chain can be sharp. Use safety
gloves when handling chains.
5.2 Prepare for operation
Note: For a video demonstration of how to install
and operate the machine, go to Markusson.se.
5.2.1 Prepare the grinding wheel
WARNING Before a chain is sharpened, make
sure that the grinding wheel is not cracked, does
not vibrate or wobble. Perform a “ring test”; see
section 4.5, “Install and center the grinding wheel”. If
the grinding wheel is damaged, it must be replaced
immediately; see section 6.3, “Change the grinding
wheel and fit the grinding wheel guard”.
If abnormal vibrations occur during operation,
immediately stop the machine and check the
condition of the grinding wheel. Make sure all the
switches are turned off before turning the power
back on.
Note: Before each chain is sharpened, make sure
the grinding wheel edges match the shape of the
chain type.
The condition, type and profile of the grinding wheel
is essential for the machine’s accurate operation.
The instructions that follow contain information on
how to make sure that the grinding wheel is in good
condition and has the correct profile.

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Operation
5. Set the grinding wheel switch to OFF.
6. Use the profile template to verify that the
grinding wheel has the same profile as the type
of chain to be sharpened.
7. Repeat steps 4-7 until the grinding wheel profile
is the same as the selected profile on the
profile template.
5.2.2 Set the head-tilt angle
Note: Read the specifications from the chain
manufacturer to find out the recommended head-tilt
angle for your chain.
1. Loosen the head-tilt angle knob located on the
back of the machine.
2. Turn the grinding head to set the desired head-tilt
angle (50-90°) on the head-tilt angle scale. The
default head-tilt angle is 60°.
3. Tighten the head-tilt angle knob.
5.2.3 Set the top-plate angle
Note: Read the specifications from the chain
manufacturer to find out the recommended top-plate
angle for your chain.
1. Loosen the top-plate angle screw up to three
turns.
2. Turn the grinding head to set the desired
top-plate angle (0-35°) on the top-plate angle
scale. The default top-plate angle is 30°.
3. Tighten the top-plate angle knob.
70°
80°
90°
60°
50°

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19 RJ12_v1_EN_220223
Operation
5.2.4 Insert the chain
CAUTION Always wear safety gloves,
protective glasses, and any other personal
protective equipment suitable for the current
work task.
1. Check the chain for double cutters (2 left
cutters or 2 right cutters) or double tie straps,
and make sure that the chain is not damaged.
Mark double cutters or double tie straps to
make it easier to see them when the chain is
sharpened.
2. Attach the stop clamp on a tie-strap between
double cutters.
3. Place the chain, with the cutter to the left of the
depth gauge, into the groove on the chain vise.
4. Attach the chain weight to the chain.
Note: Chain weight not included but is available
as accessory.
5. Pull the chain around by hand to make sure
that it runs freely in the chain vise.
CAUTION Always wear safety gloves,
protective glasses, and any other personal
protective equipment suitable for the current
work task.
5.2.5 Set the chain pusher
1. Press the power button to turn on the machine.
2. Loosen the knob and place the grinding head
in the correct position for grinding the left or
right tooth. The machine will run a full turn to
grind the cutting teeth on the selected side until
the stop clamp turns off the machine. Then
manually lift the grinding head and adjust the
grinding wheel head to the opposite side (e.g.
from 30° left to 30° right). Thereafter lower
the grinding head and then grind the chain
completely a full turn until the stop clamp turns
off the machine.
3. Lift the grinding head to its uppermost position.
4. Read the specifications from the chain
manufacturer to find the pitch for the chain that
is to be sharpened. If you don’t know the
correct pitch, calculate it by measuring the
distance in inches between 3 rivets, and divide
it by 2.
X
X÷2=

RJ12
20 RJ12_v1_EN_220223
Operation
5. Loosen the chain pitch wing-nut and move it to
the correct pitch position. Tighten it again.
Note: Adjusting the pitch is not the same thing
as adjusting the cutting tooth length (see section
5.2.7, “Set the cutter top plate to equal lengths”).
6. Set the chain pusher switch to ON. The chain
pusher arm now advances the chain forward.
7. Visually make sure that the chain pusher stops
its movement exactly above the rivet behind the
cutting link, as illustrated in the image below.
8. Set the chain pusher switch to OFF, when the
grinding head is in its uppermost position and
the chain lock is not engaged.
9. Repeat steps 5-8 until the chain pusher stops in
the correct position.
CAUTION If the pitch is not correctly set,
the chain will be pushed into an incorrect
sharpening position. This may result in a
damaged chain.
5.2.6 Set the grinding depth
CAUTION If the metal of a cutting link turns
blue during grinding, the speed is set too high and
the metal is overheated. This can cause the metal
in the cutter to lose its properties. Avoid this by
grinding off less material during each turn, and - if
needed - do more turns.
1. Fold the grinding head down to its grinding
position.