Cutting oils for flat glass processing
Why to use cutting oil?
The glass cutting is generally done in 2 steps
1/Achievement of a crack on the glass surface
2/Breaking with a mechanical action, moves the crack up to the other side of the glass.
For glass under 10 mm, the breaking is not necessary because the glass is completely cut (open cut).
The cutting is done by a diamond tool (mini disk).
The parameter to adjust to have a good cutting
-The tool angle with the glass surface
-The cutting speed
-The cutting pressure
-The tool diameter
The crack must be perpendicular to the glass surface, and without (no other crack starting from the main crack)
The tool cuts the chemical links between the silica atoms. But the glass is a viscous material. So depending the temperature, the time before cutting and breaking some links can be created again, doing the breaking more difficult.
Moreover during the cutting some very small glass pieces can link with the surface or create scratches on the glass.
Glass oil cutting action
-Improves the crack quality (direction, less alternative cracks)
-Prevents the new silica links
-The glass surface lubrication decreases the scratches number and improves the life duration for the cutting tool.
-The small glass pieces created during cutting remain next to the cutting area.
Glass cutting oils different types
At the beginning were only used mineral cutting oils. But they were difficult to remove and let marks on the glass during the following processing (tempering, laminated glass cutting, fusing…)
After washable cutting oils were proposed.
But if these cutting oils were not removed before the following processing they let also marks on the glass during heat treatments or polluted other processing.
Then evaporable cutting oils were designed.
With variable time before the evaporation to have the best efficiency
The cutting oils must not affect the material where they are used (wood, plastic, cutting table carpet…), Low e glass, mirrors….And more important the operators.
There are a lot of different cutting oils depending the glasses thickness, the cutting type (straight or shaped..).