[pjdeb]

Tom,

What you have with the "good" photo are rollers with machined trunion ends. The holes in the retainers are machined/drilled, perhaps pierced depending on the retainer thickness. A typical solid race roller bearing.

From what you describe as the junk, the rollers are spherical end, probably produced by tumbling in a barrel. The dimples are produced by stamping, probably in the same operation when the blank is pierced. Spherical end rollers are generally used in drawn cup needle bearings where there is radial load, but very little end load.

Given the design you describe, the rollers will skew with even the slightest misalignment (caused by inconsistent roller diameters, torque, etc., the bearing will self-destruct.

Poor quality, perhaps, but more than that wrong design for the application.