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I previously worked on Virtual Reality and other hardware at Valve.  I currently work at Google[x].

Prior to starting at Valve, I built computer peripherals such as keyboards, mice, and joysticks that were designed to be used inside MRI machines.  My company, Mag Design and Engineering, sold these devices directly to researchers at academic institutions who used them to publish scientific papers in peer-reviewed journals.

After work, I spend time on many different types of projects that usually involve circuit design, machining, material selection, and general fabrication/hacking.  My favorite place to be is my home workshop.

ben dot krasnow at gmail




Saturday, October 1, 2011

Effect of long-term high pressure CO2 on acrylic

I left my supercritical CO2 chamber charged up with 750 psi liquid CO2 (not supercritical) for about a week. I then depressurized the chamber, and opened it. At first, the acrylic seemed fine with just minor surface crazing. After a few hours, I was surprised to find the acrylic had deformed in a major way and was full of CO2 bubbles. Weird!


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  2. Is this the same effect as seen when diving and arising too fast from deep water? In this circumstance, the air that has been compressed and went into your blood expands so quickly that your blood might boil, which kills you.
    If you let the Co2 out slowly, the deformation could be avoided, it just needs some time to diffuse out of the acrylic again.

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  4. Hmm. CO2 is quite heavy already. Which gas should not dissolve into acrylic? Wouldn't it be possible to have a pressure regulator that streams out the gas over a period of 10 hours?

  5. What about plating the acrylic with glass, creating a diffusion barrier? Sandwiching the thick plastic with thinner glass, gluing it to the plastic in the same way laminated car windowshields are made?