K40 Original mirror damage laser on TH

[ivantandy]

My mirror got burned right through the other day- the surface was already in poor shape as a result of PSU malfunction.

[Tech_Marco]

Did you have air-assisted installed? It seems that the surface got smoked on a lot. When the surface is dirty, heat accumulated and due to the diffential of temperature (plus too much pressure on the lens holder), it could crack your lens


Marco

[ivantandy]

No I have not changed to air assist nozzle yet. I think this cracked mirror occurred when I selected High in LaserCAD at 98 power... when i hit Laser button it fired high but also did not switch beam off. The simple box does not activate laser in TL and I followed forum suggestion to change TTL level to high from low with bad result. At this time I do not know if i have a problem with the PSU I purchased from you. I may have to get replacement to test.
<UPDATE> Replaced original K40 mirrors with Si plated mirrors. Beam and cut quality is very good. I have not made any other changes to focus lens or air assist nozzle upgrade. PSU issue due to known problem with 40W PSU. I am still upgrading the K40 at this time.