KERFBY KINETIC CARVING
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Setup & CalibrationModule 4.1~1 min read

Mirror Alignment

Even on a Thunder, mirrors drift slightly over time. Catch it before cuts go wonky.

TOP VIEW: TUBE TO HEADlaser tube (fixed)M1M2M3 + lensYXgantry rail carries M2 and the headThree mirrors relay the beam from afixed tube to a head that moves.SIDE VIEW: INSIDE THE HEADfrom M2M3focus lensnozzle+ airfocal pointM3 turns the beam down through thelens, which focuses it on the work.
What you are aligning: the beam has to land in the center of M2 and M3 at every gantry position, then go straight down through the lens.

The tape test

  1. Tape (low-tack) over each mirror in turn.
  2. Pulse the laser at low power.
  3. Beam burns a dot in the tape, you see exactly where it's hitting.
  4. Goal: dot is centered on the mirror at all gantry positions (front-left, front-right, back-left, back-right).

Adjustment order

  1. Mirror 1 (tube → M1), adjust if dot is off at the M2 mirror.
  2. Mirror 2 (M1 → M2), adjust if dot drifts as gantry moves on X.
  3. Mirror 3 (M2 → lens), adjust if dot drifts as gantry moves on Y.
  4. Lens centering, beam through the nozzle should be dead-center.
Watch for
Tiny adjustments only. The screws are sensitive, quarter-turn at most before re-testing. If you can't get alignment without huge moves, something is mounted loose; investigate before adjusting.