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Some real life experiences/observations regarding this topic.
In another thread there was a short discussion regarding PVA vs PVB and a comment was made that auto glass uses PVB and that it doesn't suffer cataracts. Well I've run a car restoration shop and cataracts are actually fairly common, especially on vent windows (remember those?) and flat side glass. Have even seen them creep from the edges of some windshields.
Speaking of auto glass...had a first generation Mazda RX-7 that lost one of the spade connectors for the printed circuit defroster on the rear window (which was a hatchback). Removed the window and sat it upside down on some blankets. Using a soldering iron I was able to solder a replacement connector and left it to cool. Maybe 10-15 minutes later glass was raining down after the damn thing exploded. The interesting thing is that this was bonded safety glass AND had a metal frame around it...add to the equation that unlike a CRT there was no vacuum to contend with and I'm now even more ascared of working on picture tubes. Obviously I induced an incredible amount of localized stress. Mazdas may make you go "Hmmm" but in this case I went "WHATTHEHELLJUSTHAPPNED?!"
Regarding whether rebonding the safety glass is stronger (or not) then just sealing it around the periphery I vote that the original full face bond is stronger. Just stands to reason that the bond effectively doubles the thickness of the individual glass layers, plus it probably adds shear strength as well. Think of where plywood gets it strength from, layers of opposing grains of wood PLUS glue in between.
I could be completely wrong but that's my take on it.
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