Sorry if this has been asked a million times before, can’t see it from my research!
I’ve just bought 2x K40 cutters second hand. One with the digital control panel had a broken/cracked laser tube, the other fully functioning (according to seller) but with an older case and analog pot control.
So I took the “good” laser unit from the older machine and placed it in the newer, digital control, machine. Laser fires fine, purple plasma, but there does not appear to be a beam exiting the laser. With laser goggles on I tried holding some brown tape between the laser and first mirror, no scorching or cutting. Tried on 30% and 80% power. Is there a warm up period? Any help appreciated.