Frequently Asked Questions (FAQ)

We have collected many of the most frequently asked questions and answer them here.

General Questions (11)

  • The PUK is a fine welding machine based on TIG welding technology.
  • It generates an arc, also called plasma, for a brief moment, which generates a spot weld.
  • The welding spots have diameters of approx. 0.2 – 3.7 mm.
  • An electrode made of tungsten is clamped in the handpiece of the PUK, and the arc is ignited from its tip.
  • Tungsten is the metal with the highest melting point (3422°C) – the electrode itself does not melt.
  • The handling of the PUK is very simple: Through a microscope equipped with an eye protection filter, one looks at the electrode and guides the workpieces to it by hand.
  • The welding spot is triggered automatically.
  • Power (%), pulse duration (ms) and various welding pulse curves can be set easily and clearly on the PUK
  • Workpieces are selectively melted and thus joined together.
  • Ideally, filler metal always has the same melting temperature as the workpiece itself (in brazing, a brazing alloy is always used which has a lower melting temperature than the workpiece). Risks due to “postflow” of solder are thus avoided.
  • No annealing of the material – so even mechanics and thin sheets can be worked on without affecting the strength.
  • No difference in color or hardness

The microscope is equipped with an electronically controlled, DIN-certified eye protection filter. This ensures triple protection of the eyes: permanent protection against glare from UV and IR light and electronically controlled LCD eye protection filter.

Maintenance is not necessary!

In normal operation, only minor costs are incurred for shielding gas and due to wear of the electrode.

The angle plays an extraordinarily significant role.

The highest penetration depth is achieved at a 90° angle to the workpiece.

When the electrode is placed at an angle, the metal tends to flow in the direction of the placed electrode. I.e. the metal (e.g. fed wire) follows the direction of movement of the electrode, it is pulled in the direction of the handpiece.

An exception to this rule is silver. (See also item 17)

The technique of PUK welding is easy to learn. Nevertheless, you should take a few hours to familiarize yourself with the device. The PUK course, which is included in the scope of delivery of the device, can be of help here. With the included stainless steel plates, you can practice material application, play with power or weld time controls, or weld a clean seam. Change the angle of the electrode to the workpiece and observe what happens. With a little practice you will easily and quickly achieve very good results. In addition, it may be useful to attend a PUK welding seminar to further deepen the techniques.

Basically, all precious metals and precious metal alloys of gold, silver, platinum and palladium can be welded. In addition, all metals can be welded that are also weldable by laser or conventional TIG welding processes.

These include: Several stainless steels, titanium and many titanium alloys, steels and non-ferrous metals and alloys.

In the current model a brass mode is stored, with this brass alloys with low zinc content can be welded well.

A special aluminum mode is stored in the current PUK model. With this mode, aluminum alloys suitable for welding can be welded particularly well by feeding welding wire. It is important here to pay attention to the choice of the appropriate welding rod.

Yes – Even metals with very different properties can be welded, e.g. gold with titanium.

However, if the physical differences are too great, as is the case with titanium and steel, welding is not possible.

The heat generated during welding is very low.

Especially for heat-sensitive areas such as gemstones, it is recommended to work with the shortest possible pulse time (the PUK04 already has a presetting for this within the metal mode).

Others (1)

All welding equipment can be handed in for disposal at the end of its service life at Lampert Werktechnik Gmbh, Ettlebener Straße 27, 97440 Werneck from Monday to Friday from 08:00 to 16:30 without prior notification. It is also possible to send the device at any time to Lampert Werktechnik as a prepaid parcel shipment with the password “Disposal” to above. Another option is to dispose of the device in the municipal disposal system (recycling center, electrical equipment grid box). Please note that, as a rule, only household quantities are accepted here and take into account the specifications of the waste disposal company.

Troubleshooting (3)

  • To adjust the flow rate, turn on your PUK and carefully open the valve of the gas cylinder. On the PUK 3, press the power control on the device; on the PUK04, activate the gas test in the “Settings” menu.
  • This will open the gas valve in the unit and the flow controller will display the actual flow rate on the right clock. A flow rate of 2 – 3 liters/minute is optimal, which would correspond approximately to a pressure of 0.4 bar.
  • Now you can set the desired value by turning the large knob at the bottom of the flow controller (please note the direction of rotation, see illustration). As long as no gas is flowing out, the flow controller shows a higher value than when the gas valve in the unit is open.

  • The protective gas flow rate is set too high:
    Make sure that the flow rate is set correctly. 2 – 3 liters/min are completely sufficient (this corresponds to approximately 0.4 bar)!

  • The electrode is clamped too long:
    The shorter the electrode protrudes from the handpiece, the better the protection provided by the argon.

  • Wrong shielding gas, insufficient quality:
    We recommend pure argon (Ar 4.6), with a purity of at least 99.996%, without additives.

  • There is dirt on the workpiece:
    Any type of dirt, polishing compound, paint, electroplated coating, etc. will burn off during welding and often leave behind large amounts of soot. Clean the workpiece thoroughly before welding.

  • The alloy of the workpiece is contaminated:
    If the metal of the workpiece has inclusions or the alloy contains metals that burn at low temperatures (zinc, lead, tin, etc.), this may cause sooting.

The electrodes used are a special alloy of tungsten and metal oxides.

These electrodes have been specially designed for use in conjunction with Lampert fine welding equipment. The electrodes have excellent welding properties, but are hard and brittle.

If the electrode is bent, for example after it has caught on the workpiece and is then “broken off”, splitting can occur.

The extreme temperature differences between the electrode tip and the electrode shaft that occur during welding also create large mechanical stresses in the electrode. Therefore, it cannot be ruled out that breakage or splitting (splitting) of the electrode may occur in isolated cases.