The optical path is the part of a laser machine that degrades silently. A simple inspection routine keeps small contamination from becoming expensive damage.
The protective window is the sacrificial part
The protective window exists to be consumed: it takes the spatter the focusing lens must never see. Inspect it on a fixed interval with a bright light against a dark background — haze, pits or burn marks mean change it now. A clouded window absorbs power, shifts focus and shows up first as inconsistent piercing.
Handle optics like the contamination risk they are
Gloves, sealed packaging opened at the machine, and the head opening pointed down while the window swaps — the routine takes one minute and avoids fingerprints that etch into coatings under beam load. Never wipe a dry optic; dust particles become scratches.
Log lens hours like engine hours
Record the install date and machine hours every time a window or lens changes. The log turns optics from a mystery cost into a predictable consumable, and a sudden change in consumption rate is an early warning for gas quality or nozzle problems upstream.
Alignment checks close the loop
After any head service, verify nozzle centring with a tape shot before production. An off-centre beam clips the nozzle, heats it, and turns a clean kerf into a directional edge difference that no parameter change will fix.
