The answer
The mill-bit wear indicator is triggered after 500 machined lenses, but MHI lenses count 2.5 times faster. For example, 200 MHI lenses equal the 500-lens threshold, while installing a new mill bit resets the wear statistics to zero.
Filed under Maintenance
The mill-bit counter is material-weighted rather than a simple count of all lenses. The manual gives the following calculation:
- 100 MHI + 250 other lenses: (100 × 2.5) + 250 = 500
- 200 MHI lenses: 200 × 2.5 = 500
- 500 other-material lenses: 500
From the edger work screen, open the mill-bit change menu and select one of two operations: installing a new mill bit or cleaning the mill bit in place. Installing a new bit resets the wear statistics; cleaning it in place does not. The mill bit must be fully inserted against the back of the chuck before the replacement tool is removed.
