I have an 80w tube about 2 years old and recently ive had a real loss of power. After doing the usual checks, mirrors, lense and alignment i was still low on power. It was then i noticed this KINK in the laser.
I think this has to be the problem but not sure how to fix it. Any ideas?
I
With what I know about glass tube lasers, I cannot even imagine how that is possible.
Hi.
First of all, thankās for sharing @Gary_G , thatās an amazing pic, and at least for me a mindboggling fault.
What little -mainly teory- I know about CO2 lasers, Iād say that itās a miracle to even witness a bent/melted discharge tube.
From what I know, the discharge tube should shatter immediately when something like that happens.
Also, the tube shouldnāt be able to fire anymore, the fact that it does is simply amazing.
There are folks here who are very well versed with CO2 theory, Iām anxious to hear what they have to say about this.
I think itās very unlikely that thatās not the problem 
.
Well thatās at least an easy one, a new tube is the fix.
As for what caused something like that to happen, I can only speculate, but since the tube has been in service for 2 years, a material or manufacturing defect is an unlikely -but always a possible- cause.
A some sort of coolant mishap is obviously always a safe guess with any mechanical CO2 laser tube malfunctions and troubles, so my guess will be that as well 
.
Thereās all sorts of other possible causes that comes to mind, like the internal mirrors being out of alignment, somehow bent discharge- or water tube, etc. but itās probably best to left the deeper speculation for those who have a strong first hand experience about the inner workings and āfault modesā of a CO2 tube.
Regards,
Sam
If itās not an AI generated image or fake dated April Foolsā Day joke , I think you should go to āThunder Laserā with this tube. They must have the greatest interest in explaining to their customers how it can happen.
To get this deformation in glass it must be heated up to approx. 600-700 degrees Celsius over a certain time, the water in the cooling tube that contains the laser beam tube itself, will even with a high flow (which there is not) boil, expand ā¦ I donāt know if this type of damage can happen when operating without waterā¦, ask Thunder.
And yes, this tube is dangerous and not suitable for use.
I canāt fathom a guess whatās going on there.
Can you show us some pictures from a couple of different anglesā¦ can you rotate the tube and take a look at it from another angle? Are you sure thatās not just distortions in the glass bending like an optical illusion?
This is a new one for me.
Itās no joke or cgi it is at the point in the tube where the inner tube is attached to the next tube.
To me, it looks like an optical illusion due to the glass around it. The beam looks undistorted in the new pictures.
ā¦in my opinion, yes. It could well indicate that the cooling system has āfailedā at some point.
New tube and keep working, sh*t happens sometimes.
It should be pointed out, that the Pink you are seeing is NOT the laser. The laser beam itself is invisible to the human eye. What you are seeing is the excited plasma that is created inside the tube. In a healthy CO2 laser, the plasma inside the gas tube glows a pinkish-purple color. This emission comes from the excited nitrogen gas within the laserās gas mixture, not the invisible CO2 laser beam itself
That makes sense. The inner glass tube is distorted, not the beam. Thanks for the new perspective!
Thatās not a crack its a bit of plant I think, Iāll be flushing it out later.
As far as the ākinkā goes it is the plasma being distorted by
the glass joints in the tube.
OK this still makes me think the tube is done, picking one up in Germany 24/29th Which is nice.
The laser cuts 3 to 6 mm ply no worries, but I used to cut 5mm acrylic at 10mm/sec at 35% it now takes two passes at 3mm/sec at 70 / 80%.
New power supply, mirrors and lens is good.
I suppose since it already in bits now would be the best time for a major clean and possibly a paint job. Sheās ten years old this will be her third tube third laser
power supply.
Cheers for the help chaps.
Just relised the original was a 60W tube with a 60W power supply, I replaced the power supply with another 60W. BUT when the tube went (my winter heating failed during a -5c spell and the tube froze and shattered).
I got an 80W/100W tube which has been running on a 60W psu for two years! Now itās on a 100W psu ho hum.
You may be running below the start speed of your machine there. I had a similar issue trying to cut 13 mm acrylic. When I slowed down below the start speed it cut worse. I looked at my ammeter and it was only running at 7 or 8 milliamps where it should have been 25. See these threads for more info on that.
Cheers Iāll check them out now.
I cross referenced this with the only comparison I could think of āplasma physics Birkland currentsā and was led to Gas ionisation āGlowingā while the beam itself continues uninterrupted.
The position of the ionisation in the tube and the abnormalities in the tubes structure suggests possible gas contamination rather than power supply or tube component issues which would have different appearances.
Are there micro-cracks in the glass?
No cracks as I rotate the tube they come and go due to distortion in the glass.
Visually the tube looks ok, Iām goig to swap back to the 60w power supply and check it out.
I will not do that. The tube is finished and dangerous to use because the glass has suffered damage and has become thinner in the exposed areas.
Send it to your dealer or to the factory and install a new proper tube to continue production.
Iām sorry but the tube is fine there are no cracks or damage, it was a visible distortion of the plasma due to to joints in the glass. Iām still picking up a new tube from Germany as we are visiting friends in Colne plus its about a Ā£150.00 cheaper.
Thanks for your concern.
