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Old 17-09-2011, 07:07 PM
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alistairsam
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Location: Box Hill North, Vic
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Quote:
Originally Posted by jenchris View Post
Inertia is a strange thing - the way a bearing is tightened will determine the point at which friction is overcome and must be determined by experiment.
The system should be balanced anyway so the mass inertia will be almost zero as there is no acceleration involved (not at 15 degree an hour at any rate.)
All you are overcoming is the stiction between the bearing surfaces and the grease.
I reckon a small scope like that will come in at 20 watts no problem - depending on your mount size
Hi,
Even if the load is balanced correctly, won't the moment of inertia be a factor to get it rotating, and won't that increase with the weight of the ota?

eg. there would be a significant difference when you try and turn the shaft by hand between a perfectly balanced ota that weighs 10kg and another balanced ota that's say 30kg on the same shaft?
how do you measure that?
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