Yikes! Another CT-100 !

[ohohyodafarted]

Originally Posted by Eric H

I think the problem is the heat from a welder would cause the glass to break, but I don't know if the two halves were joined after the glass was attached to the metal flanges or after?

Eric,

The glass components were likely made by someone like Corning, and the Kovar ultor rings were fused to the glass at the the glass factory. The front and rear sections were delivered to RCA as a completed sub component, with the Kovar ultor rings already attached to the glass.

Due to the way the Kovar ultor ring is fabricated, there is not enough heat transfer from the weld to the glass to cause breakage. In fact the mechanical design of the Kovar ultor ring was designed the way it was, specifically to take into account the prevention of heat transfer to the glass.

There is also mention in literature pertaining to the general design of Kovar components for crt's, that in some cases, copper heat sink rings could be employed to prevent heat migration. We however, have no evidence one way or the other if copper heat sink rings were used at RCA in the welding process. In the only photo of the welding process at RCA, there does not appear to be the use of copper heat sinks.