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The PUK U5 – mobile and versatile

A compact TIG pulse welder: Just where conventional TIG welders reach their technical limits, especially of their lower power ranges, our technology for fine and ultrafine weldings comes into its own – regardless of the size of the workpiece.











Facts, that speak for themselves:

  • Superior welding characteristics
  • Consistently reproducible and high quality welding results on all materials suitable for welding
  • Simple and intuitive to operate
  • Precise positioning of the welding points



  • Very low, controllable development of heat
  • Welding of even the thinnest materials
  • Makes for easier and faster repairs and soldering
  • Precise welding under the welding microscope

  • Maintenance-free technology
  • Low procurement costs, extremely good price/performance ratio
  • Compact size – fits into every workshop
  • Very low costs of consumer materials
  • Low argon consumption




Compact and versatile TIG impulse welding device

On workpieces with a thickness of down to 0.2 mm or even less it is a simple process to produce high-quality welds. That way welding spots with a diameter of approx. 0.2 mm up to more than 3.5 mm can be set (depending on material and setting).



For daily use

Our welding technology is already successfully in use in over 80 countries in a wide range of different scopes – here are just a few examples:


  • Aerospace
  • Automotive industry
  • Colleges & universities
  • Dental industry
  • Electrical engineering
  • Industrial production
  • Instrument making
  • Jewellery industry
  • Lab technology
  • Measuring technology
  • Medical technology
  • Modelmaking
  • Optics industry
  • Plant engineering
  • Precision engineering
  • Prototyping
  • Repair and welding service sector
  • Research & Development
  • Restoration
  • Sensor technology
  • Sign making
  • Trade fair construction
  • Watch industry

PUK’s operating principle is as simple as it is ingenious

As soon as the tip of the electrode of the welding hand piece touches the workpiece, the welding process starts automatically. At the contact point, under an inert gas atmosphere, a melting process takes place.


In addition to many sorts of steel, different alloys of titanium, aluminum, copper and tin, as well as various precious metals and alloys are suitable for welding. Generally, all alloys suitable for laser or TIG welding can also be welded with the PUK U5. If necessary, welding wires can easily be fed or added.




Application videos

Industrial samples
Industrial samples 2

You will love the PUK!

  • Intuitive to operate
  • Thanks to intelligent pre-settings, only 2 operating steps are necessary. Select metal group and work situation > weld!



  • Precision handpiece for precision welds
  • Solid quality and the best materials such as stainless steel and Teflon are prerequisites for precision in manufacturing and reliability in application


  • Handling the components: Sophisticated details simplify handling.



  • Premium plug connections
  • Professional screw and plug connections provide long service life and permanent safety in daily use
  • Ergonomic work: Individually set work position and comfortable hand rests for fatigue-free work.
  • Special electrodes without poisonous components. With optimal ignition and welding properties
  • Practical and fast: Plug-in nozzles and nuts allow you to quickly change electrodes without tools.
  • Premium craftsmanship in every detail

PUK makes welding simple


The operating concept of the PUK U5 combines the advantages of a modern touchscreen with the tried-and-true operation via a rotary controller. Thus the intuitive and safe setting of the device is guaranteed at all times.

Correctly set the device in two steps:


  • 1. Select metal group




  • 2. Select welding situation
    > weld!

  • Setting of welding parameters with a single rotary controller
  • I.e. power and welding time can be adjusted "blindly" according to individual need.
  • You can continue to concentrate on the workpiece.



Recommended setting range:


  • A blue bar indicates the setting range recommended by our engineers.


Helpful information by touch

Informative help windows support the intuitive operation



  • If you touch a button on the display for a longer period of time (approximately 2 seconds), a help window pops up in which the basic functions of the button are explained.


  • Then touch the help window briefly to switch back to the operating menu.

The NEWS of the PUK U5


– the further development of a proven technology...


The patent-pending system for welding process monitoring
   · New software for contact monitoring of the hand piece
   · Prevention of welding errors through interruption of weld if excessive pressure is applied to the electrode
   · Increase in service life of electrode tip
   · Prevention of tungsten inclusions on sensitive surfaces or on workpieces and materials that still require further processing
   · Improvement in the overall weld quality through more uniform processing
   · Error prevention in the handling: Increase in process reliability and more consistent quality for larger quantities
   · Learning function: More rapid and simpler learning of correct welding procedure, especially for beginners

Faster progress to better results – "blind operation" with single-handed operation. Concentration remains focused on the workpiece.


Even higher-performance LED lighting in our new premium welding microscopes. More uniform illumination of the working area - more flexible use of the microscope. These microscopes can also be used as fully equipped workplace microscopes - not just for welding.


Setting of parameters for "Power", "Time" and menu navigation with one single rotary controller.


Preselection of two different welding cycles.


Speed function (only PUK U5+) – increased heat input into the workpiece for an improved welding performance when welding on highly conductive metals and alloys (e.g. copper).

Controlled welding process when welding on material thicknesses below 0.2 mm on wires and sheet metal with lowest and precise dosing and impact of the welding energy.

Preadjusted welding parameters for a wide variety of weldable metals and alloys (such as stainless steel, Hastelloy, various precious metals, titanium and much more).


Individual device set-up using the settings menu, e.g. preselection of welding cycle, calling operating levels up on screen and hiding them again, e.g. program memory, expert level, tack welding ...


Extremely simple touchscreen operation. Now with slide function!

Quality and safety come first


Quality for your requirement: We place great value on the highest production and safety standards and guarantee the reliability of our products.

  • Quality "Made in Germany": The PUK welding devices are developed and produced in Germany.
  • Safety comes first: Our welder's eye protection systems are DIN CERTCO-tested and approved.
  • Standard-oriented: Every PUK welding system is manufactured in accordance with existing EN standards and carries a "CE" certificate of conformity.

Ease-of-use features for individual demands


  • Optimised "settings" menu
  • Simplified menu navigation with one single rotary controller
  • (De-)activation of the expert menu with 15 different welding curves
  • (De-)activation of the program memory with 20 custom programs
  • (De-)activation of the tack welding function
  • (De-)activation of the resistance welding function
  • (De-)activation of the micro mode
  • The selection of basic functions such as lighting, welding sequence, choice of language or acoustic welding signal.
  • Opening the gas valve for adjustiing the gas flow to the correct amount required

Tack welding function


For temporarily fixing metal parts

  • Using this process, two metal parts are bonded together at their contact point using resistance welding.


  • The parts can be "stuck" together so that they can then be finally attached using PUK welding or so that they can then be soldered.


  • The tack welding function is particularly well suited to processing metals with low electrical conductance. For example, steels, titanium, etc.

Resistance welding mode


The resistance welding mode can be an option for using individual solutions, e.g. in combination with a force controlled triggering of the weld.


  • Corresponding equipment has to be connected to the socket for the foot switch.


  • Using this process, two metal parts are bonded together at their contact point using resistance welding.


  • To respond to specific material conditions, various welding waveforms can be selected.



Automatic operation or foot switch


Using the foot switch can make work safer and easier when working on difficult workpiece constructions.

  • Activate the foot switch by pressing it down for 3 seconds. The automatic function of the PUK is then deactivated.
  • The white symbol top right on the display signals that foot switch operation is activated.


  • Welding is then only triggered when you press the foot switch.

At home in the metal workshop


Sensible construction for long service life and continuous operation:


  • Actively cooled (only U5+)
    The PUK U5+ is actively cooled as necessary, and can be used in continous operation.


  • High-performance welding handpiece (only U5+)
    optimized welding performance, maximum transfer of power.

Accessories and special equipment


Additional practical system components and accessories such as the electrode grinding motor, absorber, flow meter, welding wires and much more are available to meet your individual needs. Feel free to visit our accessories page.

Technical data PUK U5 / PUK U5+




Power (WIG) min./max.

Power (WIG) min./max. (U5+)

Pulse duration (WIG) min./max.
Current strength (tack welding) min./max.
Pulse duration (tack welding) min./max.
Welding speed

Speed function (U5+)
Max. charging time
Number of metal programs
Program memory
Range display with recommended
Speed function (only U5+)

Active cooling (only U5+)
Help texts you can call up
Expert menu with freely selectable
welding curves
High-frequency welds
Automatic gas pre-flow time
Gas consumption
Shielding gas


Power consumption during welding
Power consumption in maintenance operation

Dimensions (w/h/d)

Weight (U5+)

4 - 630 A

4 - 720 A

0.5 - 34 ms

80 - 700 A

0.2 - 3 ms

up to 1.4 Hz

up to 2 Hz

0.8 s












ca. 2 l/min

Argon > 99.9 %

e.g. Argon 4.6

400 VA

7 W

16 x 32 x 30 cm

8.52 kg

8.77 kg


The PUK scope of delivery


The PUK welding system is delivered with the following accessories and contains all necessary documentation and instructions:

  • All necessary terminals,  gas hose, brush and connection cable
  • Operating manual



Here you can find additional information on our welding units available for download

Informational material:

PUK U5 brochure

Operating manuals:

PUK U5 manual

Pricelist PUK U5


Dean Irvine

Artisan Jeweller
West Kempsey, Australia

Lampert PUK a must for every Jeweller




read more 

Lampert PUK a must for every Jeweller


I invested in a PUK 5 welder and was able to obtain a pay back within 6 Months. The PUK enables me to do additional repair and restoration of jewellery over traditional flame soldering methods through less heat dispersion, pinpoint control and seamless joints. I selected the PUK 5 over other welders for its quality, support service, no maintenance requirements and end welding results.

Gregory J. Lafford

Ballyfin, Ireland

The PUK proves itself invaluable – no matter the metal or alloy.



read more 

I have used various models of the PUK over the past 15 years and currently have a PUK5 at my bench. I have yet to find a more versatile machine for a jeweller’s workshop. Only imagination limits application where the PUK is involved. Whether its mounting, repair work, stone setting, engraving, or otherwise, the PUK proves itself invaluable – no matter the metal or alloy.


Sceptical? Drop by my workshop and see for yourself.

Min-Ling Hsieh

Taipei, Taiwan

I must say that nowadays working without PUK is unthinkable for me!



read more 

I made first experience with a PUK back in 2003 in State Drawing Academy Hanau. It was the PUK111 and I instantly fell in love with it.

With PUK’s help I can realize any of my ideas. It makes welding of different metals and combining them with different materials a lot easier. Especially since I often use very thin metal sheets and wires, the PUK is the perfect tool for me.

I had different PUK models in my workshop already – the PUK 3s, PUK 04 and now the PUK5 – and every new model has offered an increased accuracy and improved welding results.

That is why the PUK has become one of the most important pieces of equipment in my workshop.

I must say that nowadays working without PUK is unthinkable for me!

Luca Cristino

Germagnano, Italy

I think every goldsmith workshop needs a PUK to speed up the jewellery repairs and production.



read more 

You may take anything but my PUK from me!!!

I use it for everything made of gold, silver, steel, titanium and platinum.
I work easily on claws without having to remove the stones before.

The PUK is perfect for fixing the parts prior to soldering, for different micro repairs and also allows me to work on watches (crowns, shafts, gears and bracelets).

My PUK is a PUK3s professional plus and since I bought it, it paid for itself within the first six months already.

I think every goldsmith workshop needs a PUK to speed up the jewellery repairs and production.

Mark Sansom

Birmingham, United Kingdom

I regard the PUK as an essential tool for manufacturing and repairing jewellery and can't imagine working without it.


read more 

Doing jewellery repairs, the ability to add small areas of metal is vital and was missing for the first 25 years of my time as a jeweller.
Then I heard about the welders that were becoming available so I bought a Lampert PUK3S and several years later I am still using it for most of the repairs that I do.
It paid for itself in the first year because it saves me so much time.
It opens up new possibilities such as repairing bracelets without having to refinish them all over, retipping stones like emeralds without removing them, tacking things together before soldering, repairing porosity etc. In most cases it's faster and cleaner than soldering.

I regard it as an essential tool for manufacturing and repairing jewellery and can't imagine working without it.

Lee Molseed

Kingsbridge/Devon, United Kingdom

The PUK has saved me so much more time allowing me to do more work in a day improving productivity. No goldsmith should be without one.


read more 

I have been a goldsmith for 10 years now.
I was taught the old fashion way by a master craftsman from the Birmingham jewellery quarter
Now with this fantastic new PUK I have moved away from using a naked flame and I mainly use my PUK for most of my repairs, its faster, cleaner and when working on some delicate stones such as opal or emerald, the repair is always safe.
It has also saved me so much more time allowing me to do more work in a day improving productivity.
No goldsmith should be without one.

Gabby Williamson

Dental Technician, Toowoomba (QLD), Australia

Orthodontic soldering is now a thing of the past. The possibilities are endless with the PUK D2 TIG welder, many jobs were not possible when I was limited to soldering.

read more 

Orthodontic soldering is now a thing of the past. TIG welding is far superior in every way. The possibilities are endless with the PUK D2 TIG welder. Preparation is minimal and joins are stronger and smoother than soldering.


Since I have been using the PUK D2 I have not had any appliance breakages. Many jobs were not possible when I was limited to soldering. Now I can add small attachments to my appliances with little distortion from overheating. Intricate designs are easily and quickly added to any job with minimal preparation. Almost no finishing and polishing is needed saving much time and money. Working under the microscope makes welding much more precise.


Not only is this PUK D2 excellent, the Lampert ambassadors are also very helpful. I had many conversations with them and they were more than happy to help. They always urged me to keep in touch as they want everyone to appreciate this machine as much as they do.

David Fried

Multidisciplinary artist, New York / Düsseldorf

PUK not only solved many of the problems for the specific artworks in mind, it opened the door to many new ideas that are now possible!


read more 

"You know how some of your best ideas border on the actual doable technology? As a multidisciplinary artist, my various visions often look beyond that technical border. In many cases I must invent the tools necessary, and pursue with considerable improvisation and limitations over years. In 2013, I wanted to make artworks of pre-polished stainless steel that would be very difficult to polish after normal TIG welding due to narrow access angles.


The amazingly different PUK solution: I was very surprised and delighted to find out about the PUK, and was treated to an unusually terrific demo of it in my studio. This is a machine I could never have ‘invented’, or even imagined! And it not only solved many of the problems for the specific artworks in mind, it opened the door to many new ideas that are now possible!


And not to be overlooked: the PUK is made in Germany to highest standards, and the support can’t be beat! Lampert has proven to me to be an innovative company that cares about quality, but also knows that what they are producing, solves problems and opens your creativity."

Robert Hallett

Goldsmith, jeweler, designer
Oakmont, Pennsylvania, USA

No seam and no porosity. The PUK was already paying its own way.



read more 

I have been working with precious metal for almost 50 years and some of my tools were passed on to me by a goldsmith who began work in about 1920. The PUK settled into a workshop where the anvil, planishing hammer and draw plates are used daily.

When the PUK arrived I had a problem to solve. I had just finished a custom ring with a 2.25 carat diamond set in two very wide prongs. I hadn’t gotten quite enough platinum over the diamond to feel secure. After about 5 hours of practice with the PUK I was able to add 0.75mm of clean platinum to the top of the prongs and hammer it down over the diamond. No seam and no porosity. Just like the extra platinum had always been there.

The PUK was already paying its own way.

Victor Magnes

Goldsmith, Johannesburg, South Africa

I not only use my Puk welder for difficult jewellery repairs, it’s used in my workshop every day.



read more 

Experience with Puk 3 welder at Jewellex 2009:

"I was on a hunt for a tool machine that is going to help me to make life easy doing fine soldering to chains, retipping claws on pieces without wasting too much time or money.

I guess in the last 5 hours of a Jewellex show being the last day, this was going to be a challenge that I never knew was going to make my dream come true. Walking down one of the aisles passing jeweller after show room, I saw a guy doing something weird but it was flashing spark lighting, this drew my attention.

A dream started to unfold at that very moment, I stood and watched this gent looking through a microscope and doing something that had blown me away, welding two pieces of metal together. I started asking questions - can you solder, weld a bracelet together without taking coloured stones out, his reply was 'yes', can you weld new claws on to a ring with stones and or coloured stones again 'yes'! – I asked please can I try, so he stood up and showed me to set up to suite my vision eye focus and I started welding ok at first it was messy, I sat for over an hour experimenting and I was glued to that chair. Honestly, at this time I just had a million mind flashes of what I was going to use my Puk 3 for and how it was going to work for me making life easy and more money with less stress.

Well its now two and a half years later and I have not only used my Puk welder for difficult jewellery repairs, it’s used in my workshop every day. I have also applied it in the Opticians world, helping to repair broken frames of glasses, all makes and metals types. It’s amazing, most repairs you cannot even see the repair, as being a micro weld. The real magic using the Puk there is so little heat you hold the piece in your hand and no burns.

I can just say to the team at Lampert never stop creating new technology you guys are amazing I don’t know what I would do without my Puk welder."


Victor Magnes
Goldsmith and CEO The Jewellery Connection

Workshops News

You are interested in the possibilities of use of our fine-welding devices? Or you are searching for one or another tip on working with your PUK? Then just sign up for our Workshop-News on this webpage.


We do not offer an ordinary advertising newsletter, our only intention is to support our customers. At regular intervals, we present small suggestions or examples for correct work with the PUK, so you may use our technology as efficiently as possible.


Show workshop examples

Lampert Werktechnik GmbH
Ettlebener Strasse 27 · 97440 Werneck · Germany
Tel. +49 9722 94 59 - 0 · Fax +49 9722 94 59 - 100 · mail@lampert.info

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