[AlekZ]

Pyrex glass is a "hard" glass and therefore quite easy to work with and resistant to thermal shocks. The expansion coefficient is around 33x10 ^ -7. The situation is different with sodium and lead glasses, which are "soft" glasses. The expansion coefficient is 94 ... 106x10 ^ -7. The error in cooling and join will unfortunately break.
I mainly use soft glass to build my electron tubes, so differently to Glasslinger.

But let's go back to the regeneration of picture tubes.

I have the biggest problem with extending the "necks" of the cathode ray tubes because I do not have a large horizontal glass lathe. I perform this operation in my hands. This is possible for small picture tubes, but it's a problem for bigger.

Getters are not a problem for me. I have a lot of this parts, Italian production SAES and Polish (UNITRA ZAP). I have a lot of glass sockets and I can do sockets in laboratory scale. The construction of electron guns for black and white CRTs is possible, especially for simple types of electron guns (triode or tetrode type).

In the attachments there are some pictures of the CRT with my electron gun. This is the first cathode ray tube in which I have done almost everything: I replaced the phosphor, replaced the aquadag, and mounted an electron gun of my design. The bad contrast is because the cathode is too close to Wehnelt. Focusing and deflection is magnetic. There is Ion trap (necessary: I have not metallisation of screen).