DENTAURUM desktop Compact User manual

Instructions for use
EN
More than 20 years of Dentaurum laser welding technology.
M
M
Turnstr. 31 I 75228 Ispringen I Germany I Phone + 49 72 31 / 803 - 0 I Fax + 49 72 31 / 803 - 295
www.dentaurum.com I [email protected]

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Contents
1. General information .............................................................................................................................. 3
2. Safety information ................................................................................................................................ 4
2.1 Symbols and information .......................................................................................................................... 4
2.2 Intended use............................................................................................................................................. 4
2.3 Warranty and liability................................................................................................................................ 4
2.4 Employer‘s obligations .............................................................................................................................. 5
2.5 Personnel‘s obligations ............................................................................................................................. 5
2.6 Laser safety officer.................................................................................................................................... 5
2.7 Protection of the eyes against laser radiation ............................................................................................ 6
2.8 Protection of the skin against laser radiation ............................................................................................. 7
2.9 Further important safety issues, welding fume extraction .......................................................................... 8
2.10 Service activities........................................................................................................................................ 8
2.11 Laser warning signs .................................................................................................................................. 9
2.12 Position of laser warning signs ................................................................................................................ 10
3. Basics of the laser and welding process ............................................................................................ 11
4. Machine description ............................................................................................................................ 12
4.1 Overview ................................................................................................................................................ 12
4.2 The working chamber............................................................................................................................. 14
4.3 Design of the desktop Compact ............................................................................................................. 15
4.4 External connections............................................................................................................................... 16
4.5 Installation and starting operation........................................................................................................... 17
4.6 Operating the desktop Compact............................................................................................................. 18
5. The stereo microscope......................................................................................................................... 20
6. Setting the pulse parameters ............................................................................................................. 22
7. Operating the touch screen/working chamber ................................................................................ 25
7.1 Setting pulse parameters on touch screen............................................................................................... 25
7.2 Opening / closing safety shutter on touch screen ..................................................................................... 26
7.3 Saving / loading parameter sets on touch screen or in working chamber.................................................. 26
7.4 Resetting error message on touch screen ................................................................................................ 28
7.5 Displaying and modifying basic settings on touch screen......................................................................... 29

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8. Welding ................................................................................................................................................ 30
9. Turning off the system ........................................................................................................................ 30
10. Maintenance advice............................................................................................................................. 31
10.1 Check lists 1, 2 and 3 ............................................................................................................................. 32
10.2 Test of laser adjustment and beam path.................................................................................................. 33
10.3 Changing the protective glass................................................................................................................. 33
10.4 Check and change the filter for welding fumes ...................................................................................... 34
10.5 Opening the desktop Compact ............................................................................................................... 35
10.6 Changing cooling water and particle filter .............................................................................................. 36
10.7 Adjustment of laser welding spot according to the reticule in the stereo microscope............................... 37
11. Possible faults, causes and elimination.............................................................................................. 38
12. Spare part list ...................................................................................................................................... 42
13. Environment and disposal ................................................................................................................. 42
14. Technical data....................................................................................................................................... 43
15. EC declaration of conformity .............................................................................................................. 44
16. Confirmation of instruction ................................................................................................................ 45
17. Annex

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1. General information
Thank you for choosing the Dentaurum laser welding unit. In order for you to enjoy your laser welding unit
in the future, please take time to observe all the information in these operating instructions. According to the
EC guidelines, the Dentaurum laser welding unit is a piece of working equipment specifically designed for use in
the dental laboratory.
Unit identification
Product: Laser welding unit (Nd: YAG laser wave length 1064 nm)
Type: desktop Compact – REF 090-578-50
Company: Dentaurum GmbH & Co. KG
Turnstraße 31
75228 Ispringen
Germany
The parts to be welded are manually arranged, positioned and laser welded in the welding chamber using the
stereo microscope.
The required inert gas and the laser pulse are switched on or activated via a two-stage foot switch. During and
after the processing, the welding vapor is automatically extracted.
!Caution: The unit must be installed and put into operation by authorized, qualified personnel or
Dentaurum service technicians.
Before switching on the unit, you must have read and understood the user‘s instructions!
Switch on the device only after having done this!
Before using the unit for the first time, the relevant authorities must be informed.

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2. Safety information
2.1 Symbols and information
The following symbols indicating danger are used in these operating instructions:
!Warning: Notes on possible threat to life and health of personnel. Failure to heed this can cause serious
damage to health and even dangerous injuries.
!Caution: Note on a possibly dangerous situation.
Failure to heed this can cause minor injuries or damage to property.
2.2 Intended use
The desktop Compact is designed exclusively for welding metals. To use it for any other purpose or for anything
beyond this is to use it improperly. Dentaurum is not liable for damages caused by this. Proper use also includes
heeding all information of this manual and regular inspections and maintenance work.
!Caution: Processing non-metallic materials, especially plastics, constitutes improper use.
2.3 Warranty and liability
Our general terms and conditions of sale and delivery apply. Warranty and liability claims in the event of physical
injury or damage to persons and property are invalid if they are caused by one or more of the following:
· Improper putting into operation, operating, mounting and maintenance of the laser
· Improper use of the laser
· Operating the laser with safety facilities that are defective or improperly installed or with inoperative safety and
protective precautions
· Failure to heed the notes and information in this manual concerning the transport, storage, installation,
operation and maintenance of this laser
· Lacking supervision of wearing parts
· Unauthorized structural modifications to the laser, especially the safety precautions
· Improperly performed repairs.

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2.4 Employer‘s obligations
The employer will only allow personnel to work with this unit who
· are familiar with the basic regulations concerning safety at work and accident prevention and have been instructed
in the use of this unit
· have read and understood the safety information and the warnings in this manual and have confirmed this by
their signature (see the chapter “Confirmation of Instructions“)
· have been instructed in accordance with the valid regulations about accident prevention for laser radiation,
in particular the accident prevention regulation for laser radiation (OStrV) and the regulations of the trade
associations (BGV B2).
· Before using the unit for the first time, the relevant authorities for industrial safety (e.g. labor inspection) must
be informed.
2.5 Personnel‘s obligation
Before starting to work all personnel who work with the unit must
· heed the basic regulations concerning safety at work
· read and understand the safety information and the warnings and confirm them by their signature.
2.6 Laser safety officers
Using a class 4 laser, a competent laser safety officer must be appointed in writing by the employer. The specialist
should have training and experience in the field of laser radiation. The laser safety officer should fully understand
the safety procedures and equipment used. He is responsible for the safe operation and safety measures of the unit.

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2.7 Protection of the eyes against laser radiation
The unit is equipped to protect the eyes of the operator and other personnel around the unit.
Safety shutter
The safety shutter prevents generation of laser pulses or the unintended emission of laser radiation from the laser
source and closes,
· when the feed flap is open
· if the laser parameters are changed
· if there is no control current at the safety shutter.
The laser pulse is only operational when
the feed flap is closed
· and no laser parameters are set
· and the charging of the energy reservoir has finished
· and the two-stage foot switch has been pressed down to stage 2.
Other devices for eye protection
· The unit is equipped with a large observation window made from a laser protection polymer for safe and direct
observation of the welding process.
· The unit is equipped with an automatic glare protection in the optical path of the stereo microscope, which is
activated during welding.
· The complete laser beam path is optically sealed.
The unit fulfils all stipulations for total eye protection!
This fulfils part of the stipulations of a class I laser.
The unit does not fulfil the second part of the stipulations for a class I laser, i.e. skin protection against laser
radiation.

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2.8 Protection of the skin against laser radiation
The unit has been developed for dental applications. Every workpiece is an individual part, the processes cannot
be automated. The dental workpiece must be held with the hands as a large number of various materials with
different measurements, appearances, surface compositions and fitting tolerances are connected together in
various combinations or have to be processed at their surfaces. At the moment protective gloves against laser
radiation technically cannot be realized and would hinder or even make impossible to work on the very small parts.
The same problem exists for the use of holders, tweezers, etc. Therefore this laser has to be classified as work
equipment for the dental laboratory that bears the threat of minor injuries.
Due to the design of the unit the area of danger is reduced to the hands and arms of the operator. In case of false
operation the tissue of the skin can slightly be burnt by laser influence. In case of severe burns the operator should
seek medical treatment.
!Caution: Invisible laser radiation!
You can avoid direct laser radiation to your hands:
· Do not position your hands directly under the reticule or in the laser beam!
· Look through the stereo microscope and position the workpiece so that the welding point appears sharp within
the reticule!
· Take care that the hands do not appear – if possible – in the field of view of the stereo microscope!
· Keep your hands calm while releasing the laser pulse with the two-stage foot switch!
· Always look through the stereo microscope and control the position of your hands and the position of the
workpiece!
!Caution: Scattered laser radiation
You can avoid scattered laser radiation to your hands:
Especially objects with shiny surfaces can scatter or deflect the laser radiation so that even in longer distances of
the welding point there is a certain local danger of burning.
If possible do not wear any jewelry on arms or fingers while working with laser radiation or do not hold any shiny
surfaces directly into the laser beam.

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2.9 Further important safety issues, welding fume extraction
· The operating instructions must always be kept with the unit
· This unit is designed to weld dental metals and alloys using laser pulses, it must not be used for any other purposes
· Never place flammable or explosive substances into the welding chamber!
· During the welding procedure, health endangering vapors may be produced!
Therefore, in order to maintain clean, breathable air, the trade association recommends the use of a suitable laser
emission extractor during welding work with the laser.
The extraction unit, integrated in the desktop Compact is only permitted to extract laser emissions. It must not be
used for any other purposes, e.g. the extraction of
· highly inflammable or explosive gases
· liquids of any kind
· organic substances (e.g. acrylics).
The vent slots for intake and exhaust air (see fig. 2 on page 12) must always be unrestricted. The welding fume
extractor must only be used with the original spare filter and never without filter.
Emergency off button
The emergency off button is situated on the right of the touch screen (see fig. 2 on page 12). If a dangerous
situation should occur, the desktop Compact laser can be switched off by pressing hard against this button.
In order to re-start the unit, turn the switch in the direction of the arrow, it will automatically jump back into place.
Electrical Safety
"
The desktop Compact laser is driven by AC voltage 1-phase 200 - 240 V / 50 - 60 Hz, 10 A. In the laser there
are voltages of up to 400 V.
The laser must be connected to a three-conductor mains cable with integrated protective earthing equipment.
In order to avoid a short circuit, only de-ionised cooling water with a conduction value of < 2.5pS / cm can
be used.
!Caution: Make sure the mains plug is removed before opening the machine.
2.10 Service activities
!Caution: When carrying out service and maintenance activities, never work alone!
All work on electrical parts, optical components and structure of the machine may only
be carried out by authorized, qualified personnel or by the Dentaurum service technicians.
A second person, who should be at least familiar with the risks posed by laser radiation and high-voltage, should
always be present during service and repair activities.
!Warning: Dangerous high-voltage!
In order to ignite the flash lamp, this laser runs with high-voltage capacitors. For this reason, after having turned
off or disconnected the device, current-carrying components could still be live.

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2.11 Laser warning signs
#
Invisible laser radiation
Avoid eye or skin exposure
to direct or scattered radiation
Laser Class 4
Avoid irradiation
Emission of invisible laser radiation
➀
➁
➂

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2.12 Position of the laser warning signs
➂ID of the exit
Fig. 1: Position of the laser warning signs
Laser warning lamp
➀
➀, ➁On the
feed flap

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3. Basics of the laser and welding process
LASER = Light Amplification by Stimulated Emission of Radiation
It is a light amplification caused by stimulated emission of radiation. The light amplifier of the laser is a rod shaped
crystal of neodymium-doped yttrium aluminum garnet (Nd: YAG) stimulated by a light pulse from an external rod
shaped flash lamp. A suitable high-performance reflector guarantees a high efficiency and coupling-in rate of the
lamp light into the laser crystal. In order to send out amplified and directive laser light, two mirrors are arranged
outside the crystal so that the light coming from the crystal is reflected in itself and back to the crystal (resonator).
One of the mirrors is semi-reflecting and releases a strongly directive laser radiation from the resonator. The wave length
range of this radiation is strongly limited to 1064 nm. Due to the strong directional dependence and the narrow wave
length range, the extreme concentration of the laser energy on the workpiece is possible (focusing via a suitable lens).
This energy concentration exceeds the concentration of usual light sources many times.
The laser pulse facilitates welding by heating the workpiece in the focal area beyond the melting temperature and
liquefying the materials that are to be connected. After a relatively short laser exposure time (0.5 ms to 20 ms), the
melted materials solidify again and are tightly connected together.
Thanks to the high and short time concentration of the laser energy to a limited volume, heat is only produced
where it is needed. This feature makes the laser an excellent tool for the dental laboratory.

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4. Machine description
4.1 Overview
The desktop Compact laser welder is a very compact table-top unit for manual use. It supplies short, energy-rich
invisible laser pulses at a wavelength of 1064 nm for welding metals. Fig. 2 shows a view of the device with all of
the essential controls.
The workpieces are fed through the front feed flap into the integrated laser-safe working chamber (see fig. 3 on
page 13). The workpiece is positioned manually under the stereo microscope through the two side openings
and held to be welded. When both of your hands are inserted into the leather cuffs of the hand-access openings,
the laser radiation cannot exit the device.
Fig. 2: Front view of the desktop Compact laser
Key-operated
switch (covered)
Touch screen
Hand-access
opening left
Laser protection
window for
observing the
working chamber
Feed flap
Stereo microscope
Emergency
off button
Two-stage foot switch
Hand-access
opening right
Vent slots exhaust
Vent slots intake

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Fig. 3: desktop Compact with open feed flap
Any inert gas that may be required as well as the laser pulse are turned on and triggered using a two-stage foot
switch. During and after processing, the welding fume is automatically drawn off and filtered.
All of the important functions and settings are shown on the touch screen. These parameter settings can be modified
using the touch screen. They can also be modified in the working chamber (see fig.4 on page14). Important laser
parameters can be directly adjusted using the joysticks in the chamber without having to remove your hands out of
the working chamber.

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4.2 The working chamber
The desktop Compact working chamber contains all controls necessary for easy manual laser welding. To provide a
view of all of them, the working chamber in fig. 4 is shown from below.
At the top middle, the laser beam leaves through a focusing lens protected by protective glass.
The working chamber and the workpiece are illuminated from the right and left side of the laser exit by two
powerful halogen lamps.
The swivelling nozzle for the inert gas can be swung forward and backward. When the nozzle is in its rear position,
the flow of gas is interrupted. The height of the nozzle opening can be adjusted 5mm by turning the nozzle. When
the swivelling nozzle is in its front position, it marks the focus point of the laser. The flexible nozzle on the left side
is used to guide the inert gas precisely to the welding spot.
There is also a rigid nozzle on the right that can be used to cool the workpiece and the working chamber with
compressed air.
Fig. 4: View from below into the working chamber
The intake openings for the welding fumes filter are in the top of the chamber behind the laser exit.
The controls (2 joysticks and 2 toggle switches) are easily accessible at the bottom rear of the chamber, and they
can be monitored through the observation window.
Fastening screw
filter holder (2x)
Welding fume
extraction
Swivelling inert
gas nozzle
(Height adjust-
able by turning)
Joysticks for internal
parameter selection
Flexible inert
gas nozzle
Halogen lamp
chamber light (2x)
Cooling air nozzle
Toggle switch
Laser outlet,
safety glass

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4.3 Design of the desktop Compact
All functions for operating the desktop Compact are integrated in the compact housing. Fig. 5 shows a block diagram
of the construction.
The heart of the unit is a solid-state laser. It is pumped with a flash lamp operated by a power supply with a high
electrical efficiency. The laser flash is guided along a carefully adjusted beam path through the stereo microscope
to the workpiece.
Power
supply
Flash lamp
Cooling circuit with reservoir,
particle filter and circulating pump
Monitoring and
control electronics
Laser
Housing
Workpiece
holder and
positioning
Protection,
safety
Beam guidance
Process gas
control
Exhaust cleaning
Fig. 5: Schematic layout of the desktop Compact
A newly developed control unit precisely manages the laser pulses and monitors all of the functions necessary for
safe welding.
The filtered and purified cooling water is pumped in a closed circuit through the pumping chamber of the laser and
thereby cools the flash lamp and laser rod. The arising heat is removed to the surrounding air by a heat exchanger
and fan.
The inert gas (such as argon) necessary to protect the weld seam is supplied from the outside by a connection at
the rear of the unit (see fig.6 on page16). The inert gas can be directly guided to the welding point via a swivelling
and flexible nozzle in the working chamber. The flow of gas is controlled by the two-stage foot switch.
The welding fumes arising during welding are drawn out of the welding chamber and thoroughly filtered (see fig.4
on page 14).

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4.4 External connections
All of the external connections are at the rear of the unit (see fig.6).
The rating plate shows the serial number of the unit as well as the properties of the laser source.
Fig. 6: Connections on the back of the desktop Compact
The gas connections have a connector for tubes with a diameter of 6 mm.
Inert gas:
Recommended inert gas: Argon 4.6 (99.996% purity) according to DIN EN ISO 14175:2008-06.
Cooling air nozzle:
The maximum permissible compressed air pressure is 6 bar.
Power connection:
The power is supplied through the provided standard power cable.
The unit is operated with 200 - 240 V, 50 - 60 Hz, 10 A, single-phase
Two-stage foot switch:
The provided two-stage foot switch is connected to the 15-pin sub D socket (female). When the two-stage foot
switch is not or insufficiently connected, the status indication “Laser OK“ will light up red on the touch screen.
Rating plate
Connection
for inert
gas supply
(Argon)
Mains supply
230 V 10 A
Fuses
2x10A
Connection for
two-stage foot switch
Cooling air

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4.5 Installation and starting operation
Initial inspection
Check the packaging and the device for any visible damage. If the packaging is damaged, please report it
immediately to the shipping agent. Document the damage for later claims.
The desktop Compact weighs 50 kg. It takes two people to move or transport the device.
Check the shipment for completeness.
Only undamaged units may be used.
Setup
The surface under the unit must be flat. Compensate for small unevenness with non-slip material.
The device should be placed in a dust-free location protected from direct sunlight.
Base: 560mm wide x approx. 700mm deep.
Cooling water
De-ionized cooling water must be poured into the reservoir for the cooling circuit before initial startup.
See the chapter “Changing cooling water and particle filter” on page 36.
To prevent damage from leaking or freezing cooling water, drain the cooling water container each time you move
the unit.
Electrical connections
Before connecting to the mains, make sure that the line voltage is appropriate for the desktop Compact. The unit
is operated with 200 - 240 V, 50 - 60 Hz, 10 A, single-phase.
Connect the two-stage foot switch to the 15-pin socket next to the power connection. When the two-stage foot
switch is not or insufficiently connected, the status indication “Laser OK” will light up red on the touch screen.

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4.6 Operating the desktop Compact
The desktop Compact was designed to be very easy to use. You will quickly achieve successful welding results
when you observe the following points. The subsequent chapters offer detailed descriptions of each step.
Quick start for experienced users
BEFORE YOU TURN THE UNIT ON you must read and understand the instructions for use, especially the
safety instructions! ONLY THEN MAY YOU TURN ON THE UNIT!
1. Turn the key operated switch to start the laser (emergency off button must be released). Once “Laser OK”
lights up green on the touch screen (see fig. 2 on page 12), the laser is ready to use.
2. Position workpiece under laser head.
3. If you need inert gas, connect the gas bottle to the inert gas supply connection and adjust the appropriate gas
flow with the pressure regulator. Open the gas supply. Recommended flow: 6…8 l / min.
4. Insert the workpiece into the working chamber, and close the feed flap.
5. Adjust the stereo microscope to your personal preference.
6. Set the desired parameters for the welding process using the touch screen or the joystick in the working
chamber.
7. Open the safety shutter by pressing the “Shutter open” key on the touch screen (see chapter 7.2 on page 26).
The key must light up green.
8. Through the stereo microscope, visualize the site to be welded on the workpiece. The stereo microscope
cannot be moved. You need to move the workpiece into the line of vision and adjust the sharpness by
changing the distance.
9. Direct the appropriate inert gas nozzle toward the welding site.
10. Press the two-stage foot switch to the first switching point, and the inert gas will flow. When you press the
two-stage foot switch all the way down, the laser will emit pulses at the set value, and you can start welding.
Turning on the unit
Open the gas bottle.
Turn the key-operated switch to the front.
(If you have changed the flash lamp or cooling water, wait for approximately 1 minute until all the air bubbles leave
the cooling water circuit.)

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Inert gas
The connection for the inert gas supply is on the back of the unit (see fig. 6 on page 16).
The flow of gas to the workpiece is turned on as long as the two-stage foot switch is pressed to the first stage.
The inert gas can be directed to the welding point through both a swivelling and flexible nozzle in the working
chamber (see fig. 4 on page 14). The swivelling nozzle for the inert gas can be swung forward and backward.
When it is in the rear position, the gas flow is stopped. The height of the nozzle opening can be adjusted 5mm
by turning the nozzle.
The flexible nozzle can be shut off with a turncock.
Please attend to these hints for the gas supply:
· Gas bottle 200 l or smaller (at least 10 l)
· The gas bottle can be placed in a lying position if it is secured from rolling away
and the argon fitting is protected
· Standing bottles must be secured in accordance with regulations
· The pressure regulation for argon can be adjusted within a range of 6 - 8 l/min
· The gas hose diameter is 6 mm (outer ø)
· Do not forget: After you have finished working, close the valve on the gas bottle.
The two-stage foot switch
The two-stage foot switch is connected to the rear of the device (see fig.6 on page16). It switches in two stages.
In the first switching stage, the inert gas is released.
In the second switching stage, the laser pulses are released.
This allows the inert gas to displace the air around the welding point before welding starts to ensure an oxide-free
weld seam.