Laser not fire Crkd tube? [updt: hairline= artifact] tube OK

[ivantandy]

UPDATED in more recent post Can anyone tell from the posted pic if the tube is cracked or is this line at the output normal?
The laser tube is original "40W" tube shipped with my cheap K40 of chinese origin.

Laser tube will not fire after I shutoff the AC110 power On/OFF switch and switched on immediately OOPS the cooling fan in the PS had not even spun down yet.

The laser had been running repeat tests of the small rectangle file as I set and reset origin and set about tweaking limits/ the power was low and the file is only a few seconds.

I had been running back to back test reps for half an hour- I do not know if water temp rising above 24deg. was a factor.

After my error i again powered up and reset and sent a file the laser head moved correctly to trace cut but laser did not fire. I have since tested the laser AC110 PS and i was able to throw a spark when I pressed the test button on LASER PSU. pls. refer to pic. Laser tube did not fire ever again so I removed it.

[waltfl]

Hi
the line you pointed out is not normal it could be a production failure. if you drive your tube water temperature over 25 C ( measured not eyeballed ) then you could have damaged the tube.
you say you could fire a spark on the psu without a tube connected ? you should never do this again because with this you will destroy your psu .
did you check the wire connection on the tube??? regular a tube does not go out without anything's except if cracked and cooling water leaks out.
did you make sure that there was no air bubbles in the tube because they destroy the tube too.
greetings
waltfl

Can anyone tell from the posted pic if the tube is cracked or is this line at the output normal?
The laser tube is original "40W" tube shipped with my cheap K40 of chinese origin.

Laser tube will not fire after I shutoff the AC110 power On/OFF switch and switched on immediately OOPS the cooling fan in the PS had not even spun down yet.

The laser had been running repeat tests of the small rectangle file as I set and reset origin and set about tweaking limits/ the power was low and the file is only a few seconds.

I had been running back to back test reps for half an hour- I do not know if water temp rising above 24deg. was a factor.

After my error i again powered up and reset and sent a file the laser head moved correctly to trace cut but laser did not fire. I have since tested the laser AC110 PS and i was able to throw a spark when I pressed the test button on LASER PSU. pls. refer to pic. Laser tube did not fire ever again so I removed it.

[ivantandy]

Thanks Waltfl for the confirmation. I agree NEVER fire the laser button without a proper hookup- I just didn't have a short neon 40w and really needed to know if the PS was still working so i fired an open circuit with a good earth- once, only once very powerful and frightening spark! No air bubbles while testing AW608 time- I had slightly rotated the tube which cleared bubbles. Although before upgrade to AW608 I had been running the tube under Moshisoft and TS board with a small air bubble for a couple of hours in the past.

I will rewire the terminals at the laser tube as last ditch effort on this tube / Is a specific silicone sealant required?

[ivantandy]

Original laser tube removed and rewired at terminals with fresh regular white silicone from hardware store. Tube does not leak and does not appear cracked- the wavy line on the output side i will consider an artifact. So, original k40 tube will fire from test button on AC PSU. Thanks for the tips.