Mechanical surface damage
Typical scratches that occur when the glazing bead is knocked in or nailed if the pane is not adequately protected. The scratches usually end just before the glazing bead and run in the direction of the hammer blow.
Glass plane scratch.
Caution is advised when using glass planes on the glass surface. If the glass plane is damaged or the window is dirty, so that small grains of sand get caught under the blade, fine scratches will occur.
spalling due to mechanical attack.
Conical shells can be caused by the impact of small stones on the glass surface, e.g. during transport. Depending on the angle of impact, they are either round (vertical impact) or oval (oblique impact).
Damage to the glass surface when removing dirt with steel wool or similar cleaning agents. Such scratches are formed in the direction of cleaning, whereby usually bare surfaces become visible in the centre.
These occur when fresh, not yet hardened mortar or the like is blurred on the glass surface. The wiping direction can be clearly recognized.
Flat cleaning scratches.
If glass surfaces are cleaned with too little water and/or dirty cloth, long scratches occur analogous to the cleaning movement.
Vibrations and jerky movements can cause chafing on glass panes during transport if they are not sufficiently separated by spacer plates. The reason for this are sand grains and/or small stones that are ground between the discs and cause wide chafing marks.
Angle grinder points (Flex).
Angle grinding work near the glass panes can cause damage to the glass surface due to flying sparks. The direction of the flying sparks is clearly visible. Baked metal particles can show traces of rust on the glass over time, as well as causing shelling and small scratches.
Chemical surface damage
Flat surface leaching.
Constantly acting and repeatedly drying moisture or cement leaches (alkalis), for example from masonry overlying it, cause matt, drop-shaped burns on the glass surface.
Acidic or alkaline substances, mortar as well as sealing and sealing materials leave stains when cured, which have no defined shape and are matt.
Slingshot at VSG.
When a slingshot is fired at LSG, there is no opening, as the stones are not able to penetrate the LSG target due to the low kinetic energy. The result is an irregular, cone-shaped fracture from which short inlets originate. Usually the side of the glass (behind the foil) facing away from the bullet remains free of damage.