This video shows how a lightweight lathe such as a South Bend, Hercus, or similar can be used to flow metal so as to create a very smooth surface and also reduce stress risers on components by using the edge of a standard bearing to create a localised point of contact greater than the compressive yield strength of the material.

While the cross slide pressure isn't especially high, a scissor knurling tool would be preferable by removing the knurls and replacing with appropriate sized bearings, This would definitely be beneficial on long/thin stock that would otherwise be pushed away.