Re: [PSUBS-MAILIST] Using a commercially available hatch as an emergency esca...

[MerlinSub@t-online.de (Carsten Standfuß)]

Scuba Mask are also made from tempered glass..

- Wet sub     :  polycarbonate or acrylic or tempered glass

- Dry ambient :  polycarbonate or acrylic or tempered glass

- 1 atm.      :  only acrylic, maybe with a ambient gap 
                 and a thin cover glas (easy removable) 
                 of tempered glass or polycarbonate or 
                 acrylic to protect the pressure window. 

My hull is now here.., pictures next time..  
- regards Carsten 

Herve schrieb:
> 
> There is confusion here between materials and tradenames.
> Lexan, plexiglass... trade names.
> materials are actually: polycarbonate or acrylic.
> polycarbonate better fits view ports and windows for submersibles although
> soft enough to be scratched and wornt out rapidly.
> Tempered glass cannot be used in 1 atm subs, ambient pressure subs allow use
> of tempered glass which is much more better for viewing, clarity and are
> scratch proof.
> Tempered glass is a heat treatment of glass which renders the glass
> frangible in case of shock to avoid projection of sharpened pieces of glass,
> in the process the glass actually gain 4 times the strengh of the regular
> glass.
> Greg , Dont need an escape hatch either since the windows  could be
> shattered with the apropriate tool in case of an emergency and to get out.
> Herve
>