Re: bubbles in plastic

[Subscuba@aol.com]

Bill,

I think some of what is in the papers refers to the time I did work with my 
Polycarbonate viewing port. The material I used came from the local Builders 
Supply and was intended to be used as a window or door window. The 
Polycarbonate I used has an affinity for water which had to be baked out at 
about F 210 before I took it up to around F 300 for forming. I was never very 
happy with the process but I couldn't buy one anywhere. Most of the available 
domes are acrylic which has more history and seems to be slightly better from 
a cold flow respect although it shatters easily. There was no way I would use 
acrylic for my front port since it would have been broken many times by now. 
Also bear in mind my Sub is a Wet Sub so I don't have the problems you do 
with a 1 ATM steel burial chamber. My burial chamber is Fiberglass.

Ports seem to be a continuing problem. The PSUBS site has some vendors you 
might want to contact. 

Ken Martindale