Tracking error issues/differences are nothing compared to the destructive effect of crappy bearings. Great bearings is what put SME on the map after all!
Beyond great bearings, straight line tracking is the best since it mimics the action of the cutting lathe; but its benefits can only be realized by solving (at great expense) the other mechanical problems straight line mechanisms present.
To me, a 12" arm that is both lightweight and free of resonances implies a cost/benefit ratio that is not going to be favorable compared with a 9" arm.
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Beyond great bearings, straight line tracking is the best since it mimics the action of the cutting lathe; but its benefits can only be realized by solving (at great expense) the other mechanical problems straight line mechanisms present.
To me, a 12" arm that is both lightweight and free of resonances implies a cost/benefit ratio that is not going to be favorable compared with a 9" arm.
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