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Misifus[_2_] Misifus[_2_] is offline
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Default Turntable "suspended in a vacuum" to prevent vibrations?

Scott Dorsey wrote:
George's Pro Sound Company wrote:
at one time I sold Camera that were mounted to electron scanning
microscopes
one I personal was involved with was the on in the botony building at
cornell university
the professors there told me that a bus driving 1/4 mile away cause so much
vibration to render the microscope useless
so the scope was mounted to a 12 foot by 12 foot 25 foot deep slab of
reinforced concrete


This is normal. Mass is your friend. I have a small slab poured here
which is isolated from the rest of the building foundation and has the
lathe and turntable mounted on it. It's only a fraction of that size
but it seems to do pretty well.

I sure there were more details about suspension and stuff but this is what
it takes to eliminate common vibrations from devices


The lower the frequency, the more mass it takes.
--scott



It's not just the mass, it's also isolating that mass from other
vibrations. There was a time when such slabs were floated in a pool of
mercury, which effectively decoupled it from the ground. However, since
the demonization of Mercury, I doubt it's still used anywhere.

-Raf

--
Misifus-
Rafael Seibert

Photos: http://www.flickr.com/photos/rafiii
home: http://www.rafandsioux.com