Strange Dots outside of engraving area

[Alexa Ristow]

If your machine has a test button that allows you to hold it in and trigger a burn while the head is not moving, then place a piece of thick card or MDF about 6 inches below the nozzle. Hold the test button for at least 5 seconds. You should end up burning a largish hole through the material but, if the small dots were caused by any form of optical scatter, then these spots would also be visible. This is a way of differentiating between spots caused by optics and spots caused by random or badly times firing. Hope that it is optics because that is generally easier to fix than random firing. my previous issues with random firing were caused by static build up. My newer generation controller boards do seam to be more immune.

Regards,

[Dan Ashlin]

Still having the issue. Seemed to resolve itself for a bit, but pops up randomly

[Dan Hintz]

Just so we're chasing down the right tree... this is an electrical issue, not physical (i.e., don't worry about lens cleanliness, etc.). Something is making the tube fire. This is an ideal spot for someone with an oscilloscope... let you know if it's being commanded to fire (something in the control pathway) or if it's firing on its own (think more towards the tickle end of things... overexcited tube, etc.).

[Dan Ashlin]

Just so we're chasing down the right tree... this is an electrical issue, not physical (i.e., don't worry about lens cleanliness, etc.). Something is making the tube fire. This is an ideal spot for someone with an oscilloscope... let you know if it's being commanded to fire (something in the control pathway) or if it's firing on its own (think more towards the tickle end of things... overexcited tube, etc.).

Thanks dan. To my understanding though, Chinese laser systems do not have a tickle adjustment. I'm not sure where to look otherwise, the power supply looks fine. Could this be a sign of my tube going bad maybe? I had also thought to change out the fuse that's in the back where it plugs in?

[Dan Hintz]

Thanks dan. To my understanding though, Chinese laser systems do not have a tickle adjustment. I'm not sure where to look otherwise, the power supply looks fine. Could this be a sign of my tube going bad maybe? I had also thought to change out the fuse that's in the back where it plugs in?

I would suspect the power supply first if nothing else seems obvious... if internal regulation is going, it could be raising the output voltage enough to cause what amounts to an increased tickle (random lasing).

[Dan Ashlin]

If it helps narrow down the problem, running at lesser power seems to resolve the issue. The dots are also not at full power, as I was running some flasks with cermark at 100 power and the dots appeared, but washed off with the cermark while the rest of the design remained.