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well... then its back to the drawing board! Thank you for your informative reply Vance. David Bartsch To: personal_submersibles@psubs.org Subject: Re: [PSUBS-MAILIST] Date: Sat, 4 Jul 2009 07:13:57 -0400 From: vbra676539@aol.com David, Styrofoam is a closed cell styrene foam and will compress almost immediately. Cups will go from coffee size to shot glass size at just a couple of hundred feet. Wig stands (the head you spoke of) will be slower on the inside at shallow depths, but will distort almost immediately, just like the cups. The issue is not really about crushing the air out--it is the physical collapse of the foam chambers (the bubbles). They do on come back, once crushed. Vance -----Original Message----- From: David Bartsch <dbartsch2236@hotmail.com> To: personal_submersibles@psubs.org Sent: Sat, Jul 4, 2009 5:49 am Subject: [PSUBS-MAILIST]
I remember years ago seeing an article in a National Geographic showing Alvin in which a styrofoam head was shown after the submarine had come back up from very deep. This head was stored in an external retrieval basket and was thus subjected to the pressure of this deep dive. It was shown compared to what the head looked like prior to the dive and was quite small having most of the air within it crushed out.
How much pressure or rather how deep must styrofoam go down to expel the air within it? If it were perhaps just cups and not thicker, would it go down to say 500 feet without being crushed smaller? Anyone have any idea? I was concidering using simple styrofoam as an inexpensive sonar baffling for reletively shallow operations. How far down should this be good for without changing shape upon returning topside? David Bartsch Windows Live™: Keep your life in sync. Check it out. = Insert movie times and more without leaving Hotmail®. See how. |