Laser Cleaning
Cleaning processes must not damage, and certainly must not destroy, original and valuable masonry surfaces.
For this reason, we have been using the ND:YAG laser technique to clean valuable stone objects for almost three decades. (St. Stephen's Cathedral, Vienna; Minorite Church, Vienna; Bad Deutsch-Altenburg Basilica, Lower Austria; Carnuntum Archaeological Museum, Lower Austria; Palazzo Pubblico, Siena, etc.)
The devices are powered by an yttrium aluminium garnet (YAG) rod, which is a carrier of amorphous glass treated with neodymium (Nd.), a mineral that allows photons (light quantums) to be produced in the required wavelength (1064 nm = infrared). The key advantage of this technique is the short duration of its light pulses, at less than 10 ns (nanoseconds). Each pulse creates a shockwave in the layer of deposit and dirt. The micro-resonance causes the dirt to become dislodged without damaging the underlying stone because this reflects the beam.
The stripping properties can be adjusted precisely, which also means that it is possible to retain "patina layers" on the surface caused by age.
Related projects
Related articles
Stone restoration on Seidenstraße
01/02/2012
When a stone restorer from Wachau, Austria, stone carver and stonemason named Erich Pummer is invited along with his team to Azerbaijan, one can assume its principals have been well informed.
"Monumento Salzburg 2014"
16/01/2014 - 18/01/2014
Also this year, we enjoyed many visitors to our booth at the Monument in 2014 and would like to thank you this way for your interest.
"Monumento Salzburg 2012"
08/03/2012
Successful start for Monumento 2012 The first trade fair for conservation of historic monuments in Salzburg For three days, the spirit of times long passed imbued the halls of Messezentrum Salzburg. Experts and enthusiasts of historical artifacts enjoyed the opportunity to explore the…
Once around the cathedral in 30 years
20/09/2023
Only available in German.
Further references
| Title | Location | Client | Year | Technologies |
|---|---|---|---|---|
| Museum Carnuntum, fragments of sculptures | Carnuntum, Lower Austria | Provincial Government of Lower Austria | 1999 |  |
| Heidentor Carnuntum, Roman altars | Carnuntum, Lower Austria | Provincial Government of Lower Austria | 1999 | |
| Mozart monument in Burggarten | Vienna | Burghauptmannschaft Austria | 2001 | |
| Parish church of Tulln, 10 epitaphs of sandstone and limestone on the outer facades, 16th - 18th century | Tulln, Lower Austria | Diocese of St. Pölten | 2007 | |
| Basilica Choir 1998-2001, Laser Project | Bad Deutsch-Altenburg, Lower Austria | Archdiocese of Vienna | 1999 | |
| Villa Plecnik Vienna, laser cleaning of Art Nouveau stucco | Vienna Hietzing | University of Applied Arts Vienna | 2001 | |
| Ölberg relief, Parish church of Melk, 1502 | Melk, Lower Austria | Diocese of St. Pölten, Parish of Melk | 2002 | |