RE: [PSUBS-MAILIST] RV: View ports

While glass can be stronger than acrylyc, and could potentially be used in a submersible. The biggest issue is the fact that when it fails it fais catastrophically. That means that once it fails it will shatter to pieces. On the other hand, acrylic can survive cracks under presure and not give up. The best example of this is the Trieste. During one of the dive into the Challenger deep in the Marianas Trench it cracked before they reached the bottom, however they continued their dive and finished it successfuly. Had that viewport been made out of glass, the outcome woulf have been completely different.

De: Daniel Tortolani - Tordaca [mailto:daniel@tordaca.com]
Enviado el: sábado, 23 de julio de 2005 9:11
Para: 'owner-personal_submersibles@psubs.org'
Asunto: View ports

Hello, I was wondering why all submarine Windows that I find on the web are acrylic (Plexiglas) and not glass; I couldn't get anyone to quote me the acrylics view ports for the KM-350, not even the companies listed in the psubs website, so I tried to get them local and I couldn't find 2 inch thick Plexiglas either, what I did find is laminated industrial glass, custom made to the specs I gave them, and they guarantied me that it will resist up to 800 PSI, also the sales agent told me that I couldn't break that glass not even if I shoot it with an Uzi. Does any one know the differences, advantages and disadvantages of using glass instead of Plexiglas?

Daniel.