Laski Predator User manual

„Orig. version:"07.2020
OPERATING INSTRUCTIONS
STUMP CUTTER
Predátor P56 RX

2
Foreword
Thank you very much that you have just purchased our product, the stump cutter P 50 R Predator. Our
company has been engaged in production of equipment for stump cutting, wood residue crushing and
disposal for many years and has gained considerable experiences in this field. Quality of our small and
also powerful machines is proven in 40 countries of Europe and Asia we export to.
Permanent innovations of the Laski manufacturing assortment have been crowned by the most important
awards in the company’s history, thegolden medals Grand Prix,gained for its complete familyof products
at the international shows Techagro und Silva Regina in Brno:
Grand Prix Techagro 1998
Grand Prix Silva Regina 2002
Grand Prix Silva Regina 2008
This manual brings important instructions for users, i.e. instructions for putting the machine into
operation, work safety and operating experiences. You will learn how to carry out maintenance, repairs
and servicing and who is authorised for doing checks and other actions on the machine.
Your local dealer will give you this manual with instructions for operation and maintenance while taking
this new machine over. Make sure if you understand everything. If not, do not hesitate and contact your
dealer and ask him for further explanation. It is very important for you and your work safety to understand
all instructions given in this manual.
The firm Laski s.r.o. does not bear any responsibility for any claims resulting from disobedience to the
instructions given in this manual.
This operation manual includes also work safety instructions in various parts of its text. If there is any
work safety rule or instruction in general description, then this instruction is indicated with the following
symbol:

Contents
FOREWORD..........................................................................................................2
CONTENTS............................................................................................................3
..................................................................................................................................5
WORK SAFETY INSTRUCTIONS.....................................................................8
UTILISATION .........................................................................................................8
NOT ALLOWED USE ..............................................................................................8
GENERALLY..........................................................................................................8
RESIDUAL RISKS.............................................................................................13
WORK SAFETY SYMBOLS..............................................................................14
TECHNICAL DESCRIPTION...........................................................................16
TRANSPORT.......................................................................................................19
PRODUCT DELIVERY......................................................................................20
HANDLING..........................................................................................................20
PRECAUTIONS IN DESIGN.............................................................................21
CONTROLS .........................................................................................................21
NOISE AND VIBRATIONS................................................................................25
USE........................................................................................................................26
BEFORE PUTTING INTO OPERATION....................................................................26
HANDLING AND STORAGE...................................................................................29
CHECKLIST BEFORE OPERATION .........................................................................31
STARTING THE ENGINE........................................................................................32
PUTTING INTO OPERATION .........................................................................34
EMERGENCY SITUATIONS ...................................................................................36
ROUTINE MAINTENANCE ....................................................................................36
MAINTENANCE OF MULTITIP SYSTEM ................................................................37
MAINTENANCE AND REPLACEMENT OF LASKI BLADES.....................................39
LUBRICATION......................................................................................................45

Predátor P 56RX
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MAINTENANCE OF ENGINE..................................................................................46
MAINTENANCE INTERVALS.................................................................................49
FAILURES AND TROUBLESHOOTING ....................................................................50
WARRANTY........................................................................................................57
SERVICE REPORT ............................................................................................58

Predátor P 56RX
5

Predátor P 56RX
6

Predátor P 56RX
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Product Identification
Our product is identified with its serial number stamped both on the type plate and
on the chassis.
Upon take-over of the product we recommend you to fill required data in the
following form concerning the given product and your dealer.
Tab. 1 –Basic information
Product type:
…………………………………………………….
Product serial number:
……………………………………………………..
Engine type:
……………………………………………………..
Engine serial number:
……………………………………………………..
Dealer's address:
……………………………………………………..
Address of authorised service:
……………………………………………………..
Date of delivery:
……………………………………………………..
Warranty expiration date:
……………………………………………………..
Interruption of warranty period:
……………………………………………………..
The engine type plate is located under the hood
behind the air filter.
Fig. 4 –Type plates location.
The machine type plate is
placed together with the engine
type plate.

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Work Safety Instructions
Utilisation
-This product is designed for cutting away a tree stump from above ground level
to below ground level with its above-ground part up to +700 mm and its under-
ground part up to -400 mm.
-This machine is rated to climb slopes of up to 11o.
-Range of ambient temperatures allowed: from +30 to -10oC
Not Allowed Use
-This machine cannot be used for cutting of dozy stumps which could be released
and pulled out by the blades.
-Avoid any cutting if there can be some foreign matters and objects, such as
metal, glass cullet, stony debris, ceramics etc. hidden in the stump.
-Avoid driving on very soft or unstable ground. The machine could sink, slide,
slew or turn over.
-Avoid traversing along steep slopes, since there is always the danger of
overturning the machine.
-Always ascend and descend slopes with the cutting head up hill.
-Before trying to go up a slope, make sure that the engine and the hydraulic
system has reached normal operating temperature. This will help prevent
stalling.
-It is strictly forbidden to start working with removed guards, particularly with a
rear guard of the cutting head or rubber guards if missing.
-If the rear guard does not cover the head properly.
-It is forbidden to use this machine if operating temperature in the hydraulic
system exceeds 75oC.
-
Generally
-Do not use this machine without prior reading this manual. The user/owner of
this machine is obliged to instruct attendants about relevant instructions for its
operation in a demonstrable way.
-This manual should be available/accessible for attendants any time.
-This machine is allowed to be operated only by an operator who is over 18 yrs
old, physically and mentally capable and demonstrably instructed about its
operation.

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-The stump cutter is allowed to be transported to site either on a trailer or on a
low-bed truck. It is not designed to go on public roads.
-While working, wear always personal protective equipment –forestry safety
helmet with visor or goggles, protective gloves, steel toe protection boots and
working clothes properly buttoned. DO NOT wear rings, bracelets, watches,
jewellery or any other items that could be caught in the machine controls.
Always wear full protective clothing and full ear protection according to noise
level. Wear a dust mask if the ground is very dry.
-Every operator of this machine is fully responsible for any injury or damage
caused to the third persons within the operating reach of the machine.
-While working, the operator should stand at least 3 m away from the cutting
head.
-Keep this machine beyond children's and unauthorised persons' reach. Avoid
their presence while working.
-Observe the working area. If any person, children or animals approach while
cutting (within a 20 metre radius of the machine), then stop working
immediately.
-Take the time to familiarise yourself with the machine controls before
attempting to operate it and slowly build up to operating the machine at its full
capability.
-Before working learn all functions of individual controls and safety elements
and carry out functional checks before any use.
-Make sure if necessary operating and ancillary space is free and safe.
-At work in residential zones use the machine in accordance with regulations of
the local authorities to avoid disturbing of local inhabitants (noise, flying chips,
exhaust gases). Engine exhaust gases contain poisonous carbon monoxide.
-While working keep an eye on chips gathering behind the cutting head. In case
of excessive accumulation, stop the engine and wait for running the head out.
When the head stops, remove excessive chips.
-This manual describes problems and faults that may occur atwork and that could
be remedied by an instructed person. In case of other problems and faults do not
hesitate and contact the manufacturer. He is always ready to help you.
-Do never any technical changes or any actions that are neither given in this
manual nor allowed by the manufacturer. This machine, if not correctly installed
or adjusted, may run without problems now but in the future any of important
parts could get out of order or do fatal damage.
-For replacement of worn or damaged parts use always original spare parts only.
-The manufacturer does not bear responsibility for any damages or injures to the
third persons, or to other equipment and property, resulted from disobedience to
instructions given in this manual.

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-Do not put any objects or tools on the machine.
-When handing the machine over to another person make sure if all controls,
guards and other safety elements are complete and properly installed. They
serve for your safety.
-Do not use or attempt to start the stump cutter without the cutter guards, engine
covers and access covers securely in place. Failure to do so may result in
personal injury or loss of life
-Keep the given intervals for checks of bolted joints.
-Always after work clean up all parts of the machine (brush, cleaning rag).
-Any actions or servicing on the machine are allowed to be done only if the
engine is turned off, its ignition key is pulled out and the given machine blocked
properly against unwished motion. If the cutting head should remain lifted then
block the cutter arm separately against sinking.
-Do not use petrol and similar oil products as a cleaning agent.
-Keep the machine beyond the reach of naked flames.
-Any transport of persons, or of any load, on the machine is not allowed.
-Some parts of the machine may run warm (gearings, hydraulics). Do not touch
them when the machine is still running or having been just stopped. Use great
care when maintaining the hydraulic system since oil is very hot when the
machine has just finished working.
-Do not let the engine running at high speed unreasonably.
-Do not attempt to detect contingent hydraulic oil leakage directly by hand. Use
always a piece of cardboard, wooden board etc. –risk of injury by oil under high
pressure.
-Carry out regular checks of hydraulic hoses for oil leaks and their actual
condition (damage, cracks, wear).
-Do not use the machine in confined or ill-ventilated spaces. Exhaust gases
include also toxic carbon monoxide which is colourless, odourless, tasteless and
can cause death if inhaled.
-Do not use the machine under conditions of low visibility, especially at foggy
weather, when you may overlook persons coming. Operate it only at daylight or
with sufficient lighting.
-Ensure that all operators are adequately trained for operating this machine
especially with safe working practices. In case of any uncertainty with operation
of this machine ask your dealer to show proper operation in practice.
-Every training course for attending personnel should include also practical
operation under supervision of an experienced person or your dealer and
necessary work safety instructions.
-Do not carry out any repairs that are specified for authorised services only.
-Do not carry out any repair where its solution exceeds your experiences.

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-While working, particularly while transporting the machine, respect all the
applicable instructions in the concerned manual. At public road transport the
driver must keep all local regulations valid for public roads.
-This manual contains also important health and safety information and explains
the machine controls. Read and understand this manual before operating.
-While cutting, do not enter the space in direction of ejected wooden chips.
-While cutting, the operator should not stand in close proximity to the machine,
but beyond the reach of exhaust gases, i.e. in the place as stated for attendance,
see fig.
-Keep this machine beyond the children's and unauthorised persons' reach. Avoid
their presence while working.
-Observe the working area. If any person, children or animals approach while
cutting, then stop working immediately.
-Remove the ignition key to avoid accidental starting. Ensure the cutting head
has stopped rotating before undertaking any maintenance or adjustments to the
machine
-CAUTION!!! Be aware of ejected particles. They have substantial kinetic
energy. If the wooden material to be cut contains not allowed parts, such as
metal, sand, glass etc., then such objects can reach a longer distance than
wooden chips.
-The operator of this machine is fully responsible for any injury or damage
caused to the third persons within the operating reach of the machine.
-At work in residential zones use the machine in accordance with regulations of
local authorities to avoid disturbing of local inhabitants (noise, flying chips,
exhaust gases).
While working the operator is obliged:
❑to use only such a cutter which is in optimal operating condition, not damaged
through transport, storage or from previous operation,
❑to check up the working area, respectively soil bearing capacity, before work,
❑to avoid working on wet terrain, steep slopes and close to trenches with risks of
instability,
❑to avoid working with inclination exceeding the permissible limit of 11o,
❑to expand the track base before going to any slope,
❑to ascend and to descend slopes with the cutting head up hill,
❑to expand the track base and to reduce the manoeuvring speed in order to avoid
the risk of tipping the machine over and skidding,
❑to avoid turning on inclined surfaces as far as possible. When you have to turn
on slopes, try to do it on solid and non-slippery sections.

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❑to check up functions of all controls and safety elements before putting the
machine into operation,
❑to avoid disturbing other people with noise, exhaust gases or ejected flying
particles (at windy weather),
❑to protect property, vehicles and people from flying debris and to use sufficient
screening accordingly,
❑to keep traffic rules and local regulations when going or working on or nearby
public roads.
❑Do not leave the machine unattended –pull out the ignition key.
❑While working, wear always personal protective equipment - protecting shield
or goggles, protective gloves, working boots and working clothes properly
buttoned.
❑Avoid wearing free parts, such as ties, scarves and shawls, belts, jewellery etc.
In case of longer hairs use always a proper head piece. Otherwise, such a person
is not allowed to operate this machine.
❑Keep work safety symbols in proper order.
❑Check out the stump to be cut and remove all undesirable objects. If you see
such particles in ejected chips stop working immediately.
❑In case of any problems and faults at work do not hesitate and stop the machine
immediately. Any fault, particularly on rotary parts, may cause fatal and
dangerous situations.
❑Observe the working area. If any person, children or animals approach while
cutting (within a 20 metre radius of the machine), then stop working
immediately.
❑This manual describes problems and faults that may occur atwork and that could
be remedied by an instructed person. In case of other problems and faults do not
hesitate and contact the manufacturer. He is always ready to help you.
❑Do never any technical changes or any actions that are neither given in this
manual nor allowed by the manufacturer. This machine, if not correctly installed
or adjusted, may run without problems now but in the future any of important
parts could get out of order or do fatal damage.
❑Pay regular attention to all bolted joints. Keep them properly tightened.
❑Do not start the machine in confined or ill-ventilated spaces.
❑Always ensure that the cutter arm is in its top position and clear of any obstacles
before trying to start the machine
❑When having finished the work or for a break, turn off the cutting head drive
and reduce the engine speed to idling.
❑While idling, wait for about 1 minute to let the engine and its turbo-set
cool down.

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❑Use only fuel and service fluids allowed for the engine, its cooling system
and hydraulics.
Residual Risks
FUEL
Diesel fuel can be injurious to the skin - wash off as soon as possible. If taken internally seek
immediate medical attention. Refer to your local fuel supplier for the MSDS sheet.
Store diesel only in approved containers, in well ventilated, unoccupied buildings and away from
naked flames. Do not fill the fuel tank while the engine is running.
EXHAUST FUMES
Engine exhaust gases contain poisonous carbon monoxide. Carbon monoxide is odourless,
colourless and can cause death if inhaled. Avoid inhaling exhaust fumes and never run the
engine in a closed building or confined area.
HOT PARTS
Engine components can get extremely hot from operation. To prevent severe burns, do not
touch these areas while the engine is running - or immediately after it is turned off.
Never operate the engine with heat shields or guards removed.
ELECTRICAL SHOCKS
Never touch electrical wires or components while the engine is running - they can be sources of
electrical shocks.
ROTATING HEAD
When the engine is turned off, the cutting head could continue to rotate for a short while. Its
teeth are sharp and could cause damage or injury even whilst not in motion.
BATTERIES
Batteries contain acid which is corrosive and poisonous. Handle the battery with care - if
splashed there is a risk of burns and / or serious damage to eyes. Wash the affected area
immediately with lots of clean water and seek medical advice immediately. Read the battery
MSDS sheet as supplied.
EXPLOSIVE GASES
Gases, if given off from the battery, are explosive. Keep sparking and flames away.
PERSONAL SAFETY
The following personal protective equipment (P.P.E.) must be worn by the person operating this
machine and also all personnel within a 20 metre radius of the machine:
-forestry safety helmet as to EN 397 fitted with a visor as to EN 166
-heavy duty gloves as to EN 388
-full ear protection as to EN 352-3
-close fitting heavy-duty fully protecting clothing
-steel toe protection boots as to EN 345

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dust mask if the ground is very dry.
NOISE
Noise levels of 86,1 dB(A) have been recorded at the working position, i.e. in a distance of 3 m
away from the machine in duty as to EN 11201.
DUST
If the ground is very dry, a large amount of airborne dust might occur. In this situation
a corresponding respiratory mask should be worn.
HAZARDOUS BRASH
Some species of trees and bushes are poisonous and can irritate the skin or give
respiratory problems. Do not work in confined areas and if in doubt wear a respiratory
mask in addition to the P.P.E already described. Seek professional advice if you are
unsure what you are dealing with.
LIGHTING
Operate only at daylight or with sufficient lighting.
Stopping of engine
When having finished the work first turn off the cutting head drive only and reduce
the engine speed to idling. While idling, wait for about 1 minute to let the engine
and its turbo-set cool down.
Repeated and too frequent emergency stops of the engine by pressing the
emergency stop button may lead to a failure of the engine and its turbo-set.
Noise, flight
The operator is obliged to use protective equipment
Work Safety Symbols
This article introduces work safety symbols (pictographs –fig. 5) used on this
machine. Under the given pos. number there is their location on the machine
(fig. 6). These work safety symbols warn the operator against risks connected with
the machine use. Your respect to the symbol meaning is a precondition for your work
safety.
The user is obliged to keep all the work safety symbols legible, clear and
undamaged. In case of any damage or illegibility ask your local dealer or
an authorised service for a new relevant pictograph.

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1
2
3
4
5
6
Read this
operating
manual before
use.
Always follow the manual
while maintaining, servicing
or repairing the machine and
take always the switch out of
ignition.
Warning! Keep
away –ejected
objects hazard.
Warning! Hot parts
of exhaust manifold.
Warning! Keep
away –cutter arm
swings out while
working.
Warning!
Rotating parts
–pull-in
hazard.
7
8
9
10
11
12
Warning! Keep
extremities away –
squeeze hazard.
Warning! Lower
extremities injury
hazard.
Warning! Cutting
head runs out.
Warning! Close all
guards before
starting the
machine.
Warning! Risk of
high-pressure liquid
leakage.
Transport of
persons is strictly
forbidden.
13
14
15
16
17
18
Avoid working with
inclination
exceeding
permissible limit.
Lashing points.
While working, wear
heavy-duty gloves.
Wear full ear
protection.
Wear safety helmet
fitted with visor.
Wear steel toe
protection
boots.
Fig. 5 - Work Safety Symbols

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Fig. 6 - Work Safety Symbols
Technical Description
This machine consists of following main parts:
❖chassis
❖engine
❖cutter arm
❖control box
❖hydraulic system
❖
❖Chassis
This tracked chassis can change its track width. Its travel gear is powered by
hydrodrive with continuous regulation. Adjustment of the track base can be done
also by means of
a hydraulic cylinder. Profiled rubber tracks are stretched on rollers.
❖Engine
This machine is powered by the engine Kohler KDI 1903 TCR, water-cooled, three-
cylinder, power output of 56 HP. The engine is used also for hydraulic drives and
hydrogenerator of the cutting head.

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❖Cutter arm
It is intended for swinging of the cutter arm while working. Its suspension itself
provides swinging motion against the chassis. The arm, hinged in the suspension,
can move up and down and it is controlled by hydraulic cylinders. It is in fact a
hinged bearer with the cutting head attached. RH and LH cutting blades are fitted on
the head perimeter.
❖Control box
It is in fact a multifunctional remote controller SCANRECO RC 400. This radio
control unit is highly sophisticated and offers fine control to operations of the
machine. For emergency control of the machine you can use control levers
(joysticks) of hydraulic valves installed under the cover at the rear of the machine.
❖Hydraulic system
It is designed for transmission of the torque from the driving engine to the working
elements powered by a hydraulic motor. The entire system includes also an oil cooler
with filtration and electromagnetic valves.
Tab. 2 - Technical Parameters
Parameter
jednotka
hodnota
Overall length (A –fig. 7)
mm
2900/3300**
Width (B –fig. 7)
mm
800
Width (C –fig. 7)
mm
1180
Overall height (D –fig. 7)
mm
1625
Gross weight
kg
1640/1800**
Cutting depth
mm
400
Cutting height
mm
600
Swinging range
mm
1500
Max. permissible inclination
o
11
Fuel tank capacity
l
40
Hydraulic oil tank capacity
l
cca. 75
Hydraulic oil *
-
OH HV46, ISO VG46
Cutting head speed
ot./min
1350 (+/-200 )
Number of blades
pc
12
Blades with tips
pc
6
Cutting head diameter
mm
560
Engine - type
-
Kohler KDI 1903 TCR E5
Fuel ***
-
Diesel B7

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Power output
HP/kW
56/42
Number of cylinders
-
three-cylinder, four-cycle
engine
Bore/stroke
mm
88/102
Displacement
ccm
1861
Lubricating pressure at
10020oC
and idling of 850 rpm
bar
0,6
Valve play
mm
0,1
Engine oil
-
MOGUL DIESEL
L-SAPS 10W-30, API
CJ-4
Oil charge
l
7,5
Weight
kg
233
Cooling
-
liquid
Cooling fluid
-
G 12 nebo G12++
Starter
-
elektric
Battery
lead acid, 92 Ah, 12V
* For winter periods we recommend: hydraulic oil ISO VG 32
** With a dozer
*** Use the same sort of Diesel fuel as for cars (EN 590 for E.U.
- ASTM D975-09B regulation - Grade 1e 2). Usage of other sorts
of fuel may damage the engine. Do not use contaminated fuel or
a mixture of Diesel fuel and water because it may lead to a critical failure of
the engine.
• For this engine DO NOT USE any vegetable oils as a bio fuel.

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Fig. 7 - Basic dimensions of the machine
Transport
This stump cutter can be transported to site either on a trailer or on a low bed truck. It is not
designed for driving on public roads.
Rubber tracks are designed only for use on soft terrain, not for hard and
abrasive surfaces such as sand, stone, minerals, etc. Use of rubber tracks on
these surfaces can cause premature wear and deformation, hence reducing
useful life of the tracks.
Loading/unloading
- Always perform the machine loading and unloading operation with the
trailer parked on a solid and level surface.
- Ensure the hand brake is on (if fitted) and the trailer wheels are chocked prior to
attempting to move the stump cutter onto/from the trailer.
- If loading on a gradient, always ensure that the trailer wheels are adequately
chocked. Failure to do so may result in the brake de-activating and allowing the
trailer to roll. Turn the trailer to an appropriate position and chock both trailer
wheels. Do not move the trailer with the stump cutter engine running.
- Remember to use a purpose-designed ramp or a loading platform for loading and
unloading the stump cutter. The ramp must be strong enough to support the weight
of the machine (min. carrying capacity of 2000 kg).
- Make sure the slope of the ramp is less than 11°.
- Before loading the machine clean thoroughly the ramp and the loading area. Ramps
or areas that are dirty with oil, mud or ice are slippery and dangerous.

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- Avoid steering when going up or down the ramps since this can be extremely
dangerous. If it is absolutely necessary to steer, first drive the machine back down
to the ground and off the ramps or back onto the vehicle / trailer bed and then
change the direction of travel and start back up or down the ramp again.
- Expand the track base and reduce the manoeuvring speed in order to avoid the risk
of tipping the machine over and skidding.
- Never operate any control levers except for the drive control levers when going up
or down a ramp. Actuating other levers can cause the machine to become
unbalanced and tip over.
- The machine will pivot on its tracks with a see-saw type action as it is driven over
the point where the ramp meets the trailer / vehicle bed. Be careful when going
over this point. Drive slowly on ramps.
- Fasten retention chains, straps or cables to the machine chassis. Do not put them
over or against hydraulic hoses. Make sure that they do not cause damage to rubber
tracks.
- Fasten each corner of the machine and fasten the front arm to the trailer / vehicle
bed with a chain / strap or a suitable anchor.
Product Delivery
-This product is delivered completely mounted and attached to a wooden pallet.
-While handling you may use a lift truck or a crane with min. carrying capacity
of 2000 kg (suspension in the given lashing points only). For handling you need
min. ceiling height of 2 m.
-The manufacturer delivers this machine shrink-wrapped. The protective foil
protects the machine against weather effects but in no case against mechanical
damage, fall etc. The protective foil is recyclable, dispose it according to valid
local regulations.
-While putting the machine aside (e.g. at reloading) we recommend to place it
under a shelter.
-While unloading put the product always on a solid and level surface.
-It is not allowed to put it on a labile base.
-It is not allowed to put any objects or tools on the machine.
Handling
After delivery unload the machine from the transport pallet as follows: