Just got my piston and as any rightful nerd would do I had to do some math. I was curious how long it would take the piston to go down by itself without any external pressure and also how much actual air is leaking out.
First, I tried with the piston on top but that took way too long, and I lost patience, so I flipped it upside down and let the heavier cylinder be on top.
This took roughly 6 minutes and 16 seconds. I calculated the cylinder volume to be roughly 4320mm^3, not accounting for the small bore in the middle of the piston. This came out to about 0.01149 mL of air leaking out per second, ~0.266% of the volume per second, or ~3.09 x 10^17 molecules of air at STP.
That is all, the attached timelapse video would be equivalent to about 15x speed.
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