Rebuilding the 15gp22: A final report

[jhalphen]

Hi to All,

Well after 3 pages of glum news, we all need a "Booster Shot", including myself.

Here are 3 pictures of the ETF's 15GP22 after Frit-Glass resealing which took place early 2010.

In the meantime, both guns have been rebuilt, one by RACS, the other by Western. RACS routinely has some model guns rebuilt by Western, so this 2nd gun tagged along with a bunch of others sent to them.

They are now ready to do the rebuild attempt, most likely within the next 10 days. This was delayed because of an urgent batch of radar CRTs to be rebuilt ASAP while the French Navy boat was in dry dock.

Our goal is to ship a working tube early enough in April so that Steve's team has time to install it in time for the convention.

About the frit-glass process, i've had long conversations with them. They use an in-house process refined over years (starting in 1974), but i understood that there is much leeway in the mix of ingredients to cope with variable parameters such as tube size, amplitude of leaks, all glass or glass to metal seals, resistance to altitude ("flying CRTs"),...
This modifies the basic formula to target specific needs, essentially compromises between fluidity (filling cracks/metal fatigue cricks), thickness (filling large leaks, vacuum resistance and mechanical solidity), tube processing temperatures,...

The CRT is assessed for data prior to sealing, then modifications to the core frit-glass formula are determined by discussion between the Engineering Manager and the glass-working experts handling "the hot stuff".

As with all trades where years of human experience are everything, there is a grey zone between simply following the recipe and 30 years of experience of a glass worker where by instinct he will say: the mix is too fluid, thicken it, or some other simple-seeming comment which can make the difference between success or failure.

To sum it up, wish us luck, we only have ONE 15G until ETF convention time...

Best Regards, see you soon!

jhalphen