risk factors for cataracts?

[kc8adu]

anyone know what usage/storage conditions are most likely to accelerate cataracts?looks as if some mold is responsible but not in all cases.i just got a heathkit roundie that has been in a barn 20+ years with its original rca tube dated 2-63 and no sign of them.
i have opened up new tubes that were stored indoors and the faceplate was ready to fall off.

[andy]

What brand of CRT does it have? The type of bonding material seems to be the biggest factor. RCA's was the worst, developing white spots around the edge first, and eventually turning completely white around the outside of the screen. Zenith's usually just turned green around the out side. Every Sony I've seen has been perfect, but most of those are newer than the RCAs and Zeniths. Who else made CRTs with a bonded safety glass?

[kc8adu]

the tubes i am talking about are rca.
most that i have seen at onset start with a few little black dots like pepper.
zenith and sylvania go green around the edges because the resin is thickest there.

[Rob]

Originally posted by kc8adu
...i just got a heathkit roundie that has been in a barn 20+ years with its original rca tube dated 2-63 .

Ahhhh, so that's where the other Heathkit roundie has been hiding! I have one too, model GR-53A. Mine has a Sylvania tube that is not only dead but has bad cataracts. I have never run across another heathkit round color set in all my 6 years of looking for vintage TV's! By the sounds of "20 years in a barn" I guess the set isn't worth restoring?

[kc8adu]

it was in a weathertight clean barn.no bird droppings or mud daubers
it had a dropcloth over it when i got it.
it is a gr 50something.