a few chinese tube questions

[Joe Walmer]

I saw a few install instructions that all said the water outlet is supposed to be up. This is a generic 40W tube in a k40 laser. What do you guys do as procedure. Right now the electrodes are almost facing up but the water in and out are at the bottom. Most videos I see though have people mounting most tubes with the electrodes vertical.

Is there a pressure limit or flow limit I see most say 6LPM or above is recommended but anyone know what top end?

I saw a tip you should have the tube 2mm higher in the front to help with air bubbles anyone do this?

I am waiting for some telescope finder mounts and some 50mm Tube clamps to try and Replace a RF tube with this.

[Dave Sheldrake]

I saw a few install instructions that all said the water outlet is supposed to be up. This is a generic 40W tube in a k40 laser. What do you guys do as procedure. Right now the electrodes are almost facing up but the water in and out are at the bottom. Most videos I see though have people mounting most tubes with the electrodes vertical.

Always try to keep the exit up to prevent bubble, more so in the full reflector end as that's the bit that gets hottest.


Is there a pressure limit or flow limit I see most say 6LPM or above is recommended but anyone know what top end?

It's an open system so pressure should never be a problem, 3500 LPH pumps aren't unusual


I saw a tip you should have the tube 2mm higher in the front to help with air bubbles anyone do this?

You can, it will make the beam an unusual shape, you can knarl out the angle over the next two mirrors but I tend to lift the machine rather than the tube as a general rule, it's hard enough to align spots over 2.5m as it is without introducing extra potential for errors. It will affect the beam profile but on a cheap tube not to any noticable effect.


I am waiting for some telescope finder mounts and some 50mm Tube clamps to try and Replace a RF tube with this.

I believe Epilog demo'd a Glass tube machine based on one of their RF units some time ago over here at one of the shows.Was quite funny when it caught fire :)