URGENT-Get Your CRT Tubes Rebuilt Soon!

[mikeh]

Good point, I was just checking out options, $450 to $500 is big money to me.
To preserve some of these marvels of technology from the past for future use it, is now time to just pay up and get it done while it is still possible. I will contact Hawkeye and pay up.

Mike

[ohohyodafarted]

RE: 15GP22 issues.

I am working with John folsom on the 15Gp22 rebuild project.

1. There should be no issues with the viability of the phosphors regardless of whether or not the crt is under vacuum. So long as the tube has been sealed, (IE; the neck is not broken off) the phosphors should be usable.

2. Someone stated that electron guns exposed to air instantly get destroyed. That is true only for electron guns that have been activated with the RF bomber. Guns that have not had the cathodes activated are not subject to the instant destruction from air.

3. John and I have done a very through analysis of the leak issue on the
15GP22. It is our belief that the leakers have gone to air not from the glass to metal seal, but from 2 metal to metal joints that exist in the manufacture of the ultor ring. And I am NOT speaking of the arc welded joint that holds the front and rear halves of the crt together. Although frit is used in the sealing of glass to metal, and glass to glass, frit must be matched very closely to the expansion coefficients of the glass and metal or the frit will not hold. ON our project we have found an alternative material to conventional frit, that is used to seal fiber obtic glass threads into connectors that must hold a vacuum. This material will be used in the not to distant future when we attempt to do another rebuild of the 15GP22. We are currently working on some issues that need to be resolved before the next attmpt takes place. We will keep this community informed if and when we have some successes to report.

[jeyurkon]

It sounds like you guys are making some real progress. It's great that you're so dedicated to the project.

If you, or anyone, has a 15GP22 that has gone up to air and isn't otherwise rebuildable I think I could arrange to helium leak test it and determine exactly where the leaks are. I wouldn't be anxious to risk a CRT, that could be rebuilt, by having it shipped.

By any chance is the sealing material that you're referring to F113? A water thin epoxy used for bonding fibre optics into connectors? If it is F113 or a similar epoxy, I do use it for forming vacuum tight connections when I have to fabricate my own, but these are on actively pumped devices.

I don't know that I would recommend it for a permanently sealed vacuum because of its outgassing properties. On the other hand, the exposed area must be extremely small since you're repairing a leak, so it might still outlast the normal life of the CRT.

John

[vintagecollect]

Consider doing that project soon and giving some money for his efforts at Hawkeye. Scotty said it's been slow lately, Just wanted to give everyone a heads up and started this thread. I need to follow up and see if he has the tech info to do a rebuild project of mine.