Fantastic Laser Tube

Here is the lovely 40W laser tube. Chinese made and very beautiful. I love vacuum tube technology, in what ever form it comes. It is such an overt display of the incredible physics that are going on inside. Nowadays it all happens in SMDs or BGAs or some other little black blob of plastic.

 

So a brief description:

High reflector seems to be gold coated and the output coupler germanium. The electrodes I assume are nickle, judging from their colour and catalytic effect it would have.
Strangely the water cooling for the Ge is in a glass structure. I would have thought this fiddly bit of work would more easily be done in metal, not to mention the fact that glass is an insulator.

 

Anyway at this stage I trust the Chinese as the made most of the things I own!
As you may know this tube is: gas discharge tube in the centre surrounded by a water jacket which is itself surrounded by the gas reservoir. How the hell are these made? Respect to the crafts men and women involved.

So to mount the tube I needed its centre to be 115mm above the top of the frame. I have made two assumptions here (which normally turn out to be wrong...)
 1. There will be no vibration.
 2. I don't need triangulation.
 The tube is mounted on 6mm plates bolted to the top of the frame. The cradles are then on adjustable M8 threaded bar, to allow for virtical adjustment.
At this point I should mention that all these heights have been dictated by the mirror on the gantry... but that's another story.
Since this picture I have put some padding for the tube to rest in and centre itself correctly. I made allowances or that cutting the semicircle.