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  #31  
Old 12-02-2012, 05:03 PM
sweitzel sweitzel is offline
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Hey everyone! Any new news from France on the rebuild efforts?
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  #32  
Old 12-02-2012, 06:57 PM
Dude111 Dude111 is offline
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Quote:
Originally Posted by 63bird
Boy that guy has a VERY NICE SITE and business!!
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  #33  
Old 12-03-2012, 08:02 AM
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jhalphen jhalphen is offline
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Hi to All, Sweitzel,

Quote:
Hey everyone! Any new news from France on the rebuild efforts?
Recent update:
10x 15GP22s currently at RACS. A first batch of 4 tubes is undergoing the frit process. This is very time consuming: 4x frit applications & 4x cooking cycles are necessary per tube to seal the two glass to metal welds, fore and aft of the metal anode ring + a 5th frit pass on the outer rim of the metal anode.

see diagram supplied courtesy of Bob G./John F.jr/J.Yurkon

Since mid Oct, various tweakings of the frit formula have been tested to optimize smoothness and adherence.

Once the first 4 glass envelopes have been completed, partial vacuum testing will be done without a gun. Until the envelopes prove to be totally airtight, no use risking to spoil a rebuilt gun - 16 man/hours of work per tri-color gun.

Other CRT activities:
Nick (Miniman 82) built himself a B&W CRT (10BP4 type) from A to Z using NOS glassware found at RACS. The CRT is now with Nick in WI and hopefully should soon be installed in a TV chassis at the ETF.

NOS 12" glassware is planned to be used to make "repro" Mazda CRM-121's for the UK. This is a Pre-War Pyrex tube.

RACS's partner SIVE is assessing the possibility to build repro Pyrex tubes from scratch. The principle is to fold over a very large Pyrex cylinder to make the screen at one end, then fuse a much thinner diameter tube at the other end to make the neck. From the industrially available Pyrex cylinders, max screen size would be limited to 9 inches.

A transparent vessel already made using this technique is due to be sent to RACS to assess the screen's optical flatness once covered with P4 phosphor.

Some genuine Pre-War Pyrex tubes which exhibited micro-cracks and cracks around the final anode button have been sent to SIVE for Pyrex reflow (Darryl's 12AP4 for instance).

Gun rebuilds: RACS rebuilds them, but one man only is a slowdown for volume quantities, therefore looking for partners.

Contacts are being made with E-Beam (USA), Southwest Vacuum (are they still doing them?) and Thomas Electronics - we found out they have a plant in France. We had high hopes about an ex-Philips plant in Holland, alas it closed down in July.

I called RACS today and asked for a totally up to date report. Should have it tomorrow, with photos promised of the fritted 15Gs.

Best Regards

jhalphen
Paris/France
Attached Images
File Type: jpg RCA 15GP22-01 - Cross Section of Frit - General View.jpg (72.9 KB, 76 views)
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  #34  
Old 12-03-2012, 10:23 AM
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John Folsom John Folsom is offline
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Thanks for the update Jerome.
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  #35  
Old 01-15-2013, 03:57 PM
Tom9589 Tom9589 is offline
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I gave Steve McVoy contact information about the CEO of Southwest Vacuum and even spoke with the CEO, Ron Ordway. That was back in August. I haven't heard anything from Steve since then or driven by the building to see if they have vacated the premises. They are/were located in Stone Mountain, GA.

Tom Evans
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  #36  
Old 01-15-2013, 04:38 PM
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Steve McVoy Steve McVoy is offline
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Tom, we are working on it, but have no resolution yet.
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