Laser pens 870 instructions for binding

How do I clean the focus lens on my laser system?

Regular care and maintenance of your laser system is very important for optimal cutting results. In our video tutorial, we will show you step by step how to properly clean the focus lens of your laser system

(current series - G3 / S3). Quickly and easily ensure that your laser system retains its value and is in an optimal condition.

Please heed all warning notices

It may be necessary to remove or change the focus lens for inspection and cleaning purposes.
The focus lens of the eurolaser laser cutting system is built into a lens holder that can be removed from the laser tool module without having to dismantle the module from the system. The system does not have to be switched off for this removal / change. On the contrary, in order to guarantee a trouble-free process, use the tool change function integrated in the system.

  • Press the function key F4 on the control panel or enter the code 1-5-1; the laser tool module (LM-Z) can be placed anywhere on the work surface
  • Confirm the message "Start module / change tool" in the display with START
  • The LM-Z moves to the change position in the machine zero point
  • Message appears in the display: "Install / remove module / tool ..."
  • Dismantle the cover and unscrew the lens holder
  • Screw in the same holder after checking / cleaning. Check that it is fully screwed into the LM-Z
  • Mount the cover
  • Confirm the message in the display (see point 4) with OK
  • After the change, the message "Module 1: Tool manager" appears in the display with the lens recognized by the system in the line below
  • If this information does not match the actually installed lens, the holder is not fully screwed into the LM-Z or the corresponding detection button in the LM-Z is defective
  • Confirm the message with OK


  • Do not change the lens holder with the LM-Z dismantled
  • Do not change the lens holder by bypassing the tool change function

This is an unauthorized tool change, which leads to error messages and, in the worst case, to damage to the system!

Provide the following material:

  • Cleaning the lens requires dismantling the lens holder.
  • After cleaning, ensure that you reinstall the lens correctly.
    This must be installed with the curved side up. In the best case scenario, an incorrectly inserted lens leads to poor quality cutting results, but mostly to damage to the laser cutting system!
  • Place the focus optics on a clean, dust-free surface in order to then remove the lens.
  • Unscrew the brass thread on the top of the lens and carefully "tip" the lens holder onto the head so that the lens holder can then be carefully lifted off.


Care should be taken when removing the lens from the holder to avoid damaging the edges or breaking the lens.

  • Therefore, do not use any tools or hard objects to remove or clean the lens.
  • Prepare a clean and dust-free workplace for cleaning the lenses.

Light soiling (dust, lint, dirt stains, fingerprints)

  • Always hold the lens by the edge.
  • In the first cleaning step, place the lens on a sheet of lens paper. Cover the lens with another sheet of lens paper and put a few drops of acetone on the paper so that the entire surface of the lens is moistened.
  • Now pull the paper slowly over the lens without applying pressure. Usually the liquid evaporates streak-free behind the paper.
  • Turn the lens over and repeat this process with a new piece of lens paper.

If no further soiling is visible, cleaning is complete.
If you can still see soiling on the lens, continue with the second cleaning step.

  • Only use sticks made of cardboard or wood for the second cleaning step. Do not use plastic sticks as these can be dissolved by the acetone!
  • Take a new cotton swab for each cleaning step so that dirt adhering to used swabs is not rubbed onto the lens again.
  • Use a cotton swab soaked in acetone to remove light soiling without applying pressure. To do this, pull the cotton swab with a twisting motion over the surface just enough so that the liquid evaporates and no streaks remain on the lens.
  • Repeat the process until the lens is clean and streak-free.
  • Then turn the lens over and clean the back.

If dirt still adheres to the lens after performing the cleaning described above, it can be removed in a third cleaning step with a mild cleaning method.

Medium soiling (oil, water splashes)

  • Moisten a cotton swab with pure distilled vinegar and wipe the surface with light pressure and a rotating motion. Soak up any excess vinegar with a dry cotton swab.
  • Then soak a cotton swab with acetone and clean the lens of any vinegar residue. To do this, pull the cotton swab with a twisting motion over the surface just enough so that the liquid evaporates and no visible streaks remain on the lens.
  • Repeat this step until the lens is clean and streak-free.

Cleaning is no longer possible in the case of certain types of soiling from material residues, burn-in or damage from scratches.

  • Replace such lenses as a precaution. Damaged ZnSe lenses must be treated in accordance with the "ZnSe operating instructions" and disposed of by the operator.

If the lens has been completely cleaned, the focus optics can be reassembled in reverse order.

  • Place the spacer sleeve on a flat, clean surface.
  • Put on the spacer ring (red) and place the cleaned lens on it.
  • The lens must be installed with the curved side up.
  • Put the lens holder back on carefully so that the brass ring can be screwed back on.


Please observe the national laws and regulations for handling hazardous substances and the instructions in your operating manual!

  • The meniscus lenses used in the optical head of the systems must be checked daily and cleaned if they are dirty in order to ensure consistent cutting quality.
  • The cleaning and testing of lenses must only be carried out by appropriately trained personnel and is at your own risk.

The following precautionary measures must be observed when cleaning the ZnSe lenses:

  • Always observe the operating instructions for acetone and ZnSe as well as the equipment used by the operator.
  • Handle the ZnSe lens and the optical components with the utmost care. Especially if the lens is burned or broken. The particles released in this way can cause serious health hazards.
  • Avoid contact of the material with the skin.
  • Never touch the optics and lens with your bare fingers. Greasy / dirty hands contaminate the surface and shorten the life of the lens.
  • Always use finger cots or gloves made of synthetic fibers. Do not use cotton gloves, they are not low-lint.
  • Always store unused and removed lenses in the lens paper supplied
  • A lens that has scratches or burn-in must no longer be used!

 Extract from the information on the toxicology of selenium and its compounds:

  • Toxic by inhalation and if swallowed.
  • Do not eat, drink or smoke at work.
  • In case of contact with skin, wash off immediately with plenty of water.
  • Get medical advice if you feel unwell.
  • The use of acetone is recommended to clean the optical components.

Acetone hazard warnings:

  • Flammable
  • Keep out of the reach of children
  • Keep container tightly closed in a well-ventilated place
  • Keep away from sources of ignition - No smoking
  • Avoid skin contact
  • Do not empty into drains