Argon question

[paul1598419]

The air cooled systems don't have a reservoir that can out gas making it necessary to fire them up every several months to keep this from happening. Those are reserved to the higher powered, often water cooled, systems.

 

[Lasertekk]

I thînk you misread my response. Gas leaking from an autfill reservoir is one mode of increasing gas pressure failure and the other is trapped gas in the bore outgassing over time. Early Coherent innova tubes had yet another unique but similar gas issue. They were prone to hydrogen outgassing in tubes produced from 1981 to mid 1985. We solved the problem in tubes manufactured after that era.

 

[Lasergraph]

I have a Liconix 5004 Argon ion system that does 5 watts with a decent tube. My tube has suffered a catastrophic failure and I am looking for a new Liconix Argon tube, head or complete system. If any one has anything for sale please get in touch. Best regards Stuart Hall.

 

[paul1598419]

I have a Liconix 5004 Argon ion system that does 5 watts with a decent tube. My tube has suffered a catastrophic failure and I am looking for a new Liconix Argon tube, head or complete system. If any one has anything for sale please get in touch. Best regards Stuart Hall.

Bummer! That had too hurt. But, they weren't made to last forever. There are several places that rebuild these tubes. There is even one here in Washington. Have you thought about getting it repaired?

 

[Lasertekk]

I have a Liconix 5004 Argon ion system that does 5 watts with a decent tube. My tube has suffered a catastrophic failure and I am looking for a new Liconix Argon tube, head or complete system. If any one has anything for sale please get in touch. Best regards Stuart Hall.

You had a functioning Liconix head up until recently? Wow. I haven't worked on one since 1992. Liconix starting making doubled and tripled yag lasers not too long after that. They then underwent a name change to DPSS Lasers, trying to crash the stereolithography market. I can't remember, is the 5000 series the larger diameter tube like Coherent and late model Spectras? Or is it a segmented (BeO) bore small diameter like Lexels?

Elaborate on 'catastrophic failure'. Water filled? Or up to air?

 

[hakzaw1]

Had the same issue with my old Lasos LGK 7872. Was sitting for around two years and had serious issues during ignition. But after 10 or so "ticks" the laser has started. After running it for a couple of hours around 80% the issue issue got solved until today. Recommend SAMs Laser FAQ for further reading.

Laser Sam is THE man-- he will reply to email BUT please do your own searches at Sam's Laser FAQ before you contact him..
and we have a great member who has written some of what we read at Sam's
Steve Roberts--his username is.....Mixedgas (I think) I have met with him at 4 SELEMs and got the honor of spending time twice at two SELEMs w/ Sam...( I am truly blessed!)-- some of us shared a suite w/ Sam..and his major expenses were covered by members and Buffo at SELEM.... money well spent.

another post--

diachi said:
Yup, there's a thermal cutoff switch attached to the tube that's part of the interlock loop. You'll usually hear it click off and the interlock OK light will turn off if it heats up too much. Best not to do that too often.

Good advice with the airflow too, needs to pull through not push. Never did like the 2214s for cooling, cooling is easier on the 2211s (square heads).

Thanks for the kind words--I got much of my info from you and other members--just one more thing that makes this forum so great.....

 

[Lasergraph]

You had a functioning Liconix head up until recently? Wow. I haven't worked on one since 1992. Liconix starting making doubled and tripled yag lasers not too long after that. They then underwent a name change to DPSS Lasers, trying to crash the stereolithography market. I can't remember, is the 5000 series the larger diameter tube like Coherent and late model Spectras? Or is it a segmented (BeO) bore small diameter like Lexels?

Elaborate on 'catastrophic failure'. Water filled? Or up to air?

Its a BeO bore and I cant remember if its water filled or up to air, I think its up to air.

 

[Lasertekk]

Sorry about that, it's unfortunate to lose one of the last remaining Liconix tubes. The BeO bores are usually segmented. No one made long enough pieces, so you'll always see a frit joint or even a metal joining collar. Typically, these are the points of breakage. On Coherent alumina bore tubes, they tend to crack by the anode area. Interested in adapting a Lexel 95 tube? All the small frame systems operated at roughly the same voltages and currents. It was easy to mix and match. I used to do a conversion of the old Coherent 52 head, using an American 920 tube, good for 10+ watts. Ran the Coherent supply up to 40 amps. The transformer got a little toasty.

 

[Lasergraph]

You had a functioning Liconix head up until recently? Wow. I haven't worked on one since 1992. Liconix starting making doubled and tripled yag lasers not too long after that. They then underwent a name change to DPSS Lasers, trying to crash the stereolithography market. I can't remember, is the 5000 series the larger diameter tube like Coherent and late model Spectras? Or is it a segmented (BeO) bore small diameter like Lexels?

Elaborate on 'catastrophic failure'. Water filled? Or up to air?

Hi there if you have any advice etcetera on putting a coherent or lexel head on to my PSU or a coherent or Lexel tube into my resonator I would really love to hear from you. Best regards Stuart Hall.

 

[LSRFAQ]

Please do not try cathode re-flsshing on modern small tubes with Scandidate cathodes like JDSU. Blowing the emission layer off the cathode to getter the gas won't help you with these. In fact it will make it worse. These are not your classic dispenser cathode with the need to drive Barium to the surface. Scandium doped cathodes don't re-activate in that sense.

Tubes like JDSU with the larger internal gas reservoirs and copper shells rarely have outgassing. They have a very minimal amount of BeO in them.

Generally anything made since 2000 or so does not respond to the "car battery trick"

I have the Lexel factory cathode processing memos and tube processing manual. I have the Coherent field service cathode memo from. 2010 ish. Neither of them allow overdrive

With no fill systems on anything under a Watt except Coherent Enterprise series, it is rare for a hard sealed air-cooled with fritted mirrors to go high pressure. If they do outgas, it is hydrogen trapped in a weld.. Starting with a spark coil on the bench by a very experienced technician followed by a long run-in generally will get the tube recovered.

Towards the end, air cooled tube processing improved to the point that getter assemblies were no longer needed. AlC/Omni/ NEC copier surplus heads were generally the tubes with pressure issues mentioned in the FAQ.

I still suggest firing up every few months if the laser is shelved.

Steve

 

[vk2fro]

Its not uncommon for an argon that has sat for a while to "tick tick tick" for a few to several 10's of minutes, like everyone has said.

I have a just under half watt ILT multiline that when I first got it sat and ticked for quite some time. Having had experience with other argons, I let it sit and tick for 20 minutes. Unbekown to me, the power set trimmer was set to approximatly 80% of maximum, I got quite a fright when it sprang to life, the dot was very bright! I had planned for this and put a beam stop in front of the laser, just in case.

I left it at that setting for 3 hours, then shut it down, and it starts first pulse now.

So for anyone coming across this thread, as long as the laser isn't clocked up to high hours, letting it sit and tick will get results after a little while. Run it for a few hours at 70-80% power, and it should start first tick in future. Run them every 6 months for an hour to prevent constant ticking coming back.

 

[Eidetical]

In case anyone was wondering what LiConix ion lasers looked like, here are a couple of them. First is the model 5005, and the model 5102A in the final pic. Both are derived from those acquired from Continental Lasers.