Eli5 How are ball bearings made precisely spherical?

Question

So the ‘ball’ part of the bearings must have to be perfectly smooth and of uniform size to work correctly, right? So how does the manufacturing process ensure precise dimensions across all 3 axes with perfect repeatability? Also what addition complexities would arise if we take into account bearings from decades ago when the manufacturing process would not have the benefits of modern electronics?

In: Engineering

Answer 1

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