The IR laser, delicate flower that it is, tends to lose its aim when it's moved, and the beam will hit at some distance from the crosshairs.

To re-center the beam, we adjust the final turning mirror just above the focusing assembly.

>Remove the cover, paying attention to the wire from the emission lamp in the cover to the circuit board on the frame. Remove the cover just far enough to unplug the wire from the frame, before fully removing the cover.

>Bypass the cover safety interlock switch with a bit of adhesive tape <--- my favorite.

>Put a scrap of wood under the laser at the same height as the sample holder when inside the chamber. You'll need a depth gauge for the distance from the top of the chamber to the top of the holder. I get: 124 mm total chamber height - 47 mm depth to the top of sample holder = 77 mm height from the table top to the top of sample holder.

>Make sure the camera zoom is at our 50% use level.

>Referring to photo MirrorAdjust.jpg:
  >Upper right adjusts up-down, CL = move beam down, CCL = up
  >Lower left adjusts left-right, CL = move beam left, CCL = right

>Using trial and error, burn a hole, adjust, burn a hole, adjust, etc.

Other stuff:

>This unit was delivered with the default spot size table only, wherein the beam iris is 100% at all spot sizes and never changes. Spot size for this unit is controlled only by the focusing "assemlby" shown in the schematic.

>While camera zoom is controlled by a motorized lens, focus is controlled by the height of the camera (and laser) over the sample, and thus by the z-axis motor in the base.

>The "beam ex"panders on the horizontal optics tube are factory set.

>The focusing assembly for controlling spot size has been sticky since my day one here. If you ever purchase one of these, make sure all motors and gears move freely through their full range of motion before signing off on it.

>You'll be tempted to engage it as a really really expensive wood burning tool. Party on.