Can CNC process glass? Sure but dislike metal

Glass is hard and brittle, machining it is like carving an eggshell. What you need diamond tools, spindle speed between 15,000~30,000 RPM, the feed rate is around 1/10 of what you'd use on aluminum.

Common operations:

Drilling: Minimum hole size 0.3mm
Milling: flatness down to ±0.02mm
Contour cutting: Edge chip within 0.1mm.

3 real headaches:

1. Cooling: Special coolant required. Regular cutting oil? It'll spread micro cracks like crazy.

2. Parameters: Feed too fast and the edge chip out instantly.

3.Workingholding: Mechanical clamps creates stress points, you need custom vacuum chucks.

Where you will find CNC glass parts:

Phone camera sapphire lens mounts

Optical windows for miniature spectrometers

Semiconductor equipment viewports

Light guides for medical endoscopes