Have I got another bust tube.

[SillyJokes]

Only got my machine in November and within a couple of week the tube was not outputting any power, after much fiddling got HPC in and had a new tube fitted (the mirror in the old tube had been damaged by an air bubble)

My machine used to cut 3mm mdf and acrylic at speed 11, now I've wound it right down to 3 and it just about cuts (although it appears to be getting worse)
Another thing I've noticed first cut of the day seems to have more power.

Is this another bust tube, have I been really unlucky?

Here is a photo of the end of the tube.

If this is my problem how do I prevent it in the future? should the pump be running all the time not just when the laser is on.

Thanks

[PhillyDee]

As you have realised, it is vitally important to get all the air bubbles out. I myself leave the pumps running 24/7, but I have my machines in a unit at an industrial estate.

If the first cut of the day is better, then what are your water temperatures? As the water gets warmer, the efficiency drops.

Also, what are your optics like? Clean? In line etc?

[SillyJokes]

Thanks, HPC have diagnosed the tube must of been another air bubble. From now on the pump will be running 24 7.

[ncamacho2000]

The same thing happened to mine and the actual end fell off, the trapped air makes the end get very hot. I have since glued it on, but always check the end for bubbles, they seem to hold there and the only way to get rid of them is to leave the pump on or press the tubes a few times before I start the laser.

[SillyJokes]

I'm wondering if I should buy a couple of tube on eBay from China, has anyone had success doing that?

[Spooky]

The cheap chinese tubes on Ebay are junk, the good ones cost as much to get here as buying them inside the UK

cheers

Dave

[SillyJokes]

The cheap chinese tubes on Ebay are junk, the good ones cost as much to get here as buying them inside the UK

Bad low power or bad don't last long?

[PhillyDee]

Probably all three. Including poor quality. Plus, chances of getting here intact are slim.