On Thu, 9 Jun 2016 17:01:36 +0000 (UTC), Cydrome Leader
wrote:


No such thing as "standard practice" Cheap motors used plain bearings.
Many better motors used ball bearings. 50 years ago was only 1966
-ball bearings were pretty common - but usually not fully sealed or
double sheilded. Many would have been "oil lubricated"uising thick

Any reason for that, or why the shielded/sealed stuff took over? Was there
some incredible development in stamping out shields or lubricants?
'Better bearing construction, better shielding techniques, better
design and implementation

I've read that what used to be a grade 7 bearing in 1960, is now a
grade 3 bearing and what is a grade 7 today..was considered to be a
grade 9 back then

Gunner, on the road to LA

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