free play on manual focusing rings

I often notice a free play on focusing rings on manual lenses, e.g.

my Nikkors 4/200, 2/50, 2.8/55 micro have some play. Is it possible

to eliminate it? Does focusing play change image quality?

Richard,

the play will not affect the image quality. Here is my story:

 

My cousin found her father's Nikon F with a 1.4/50 lens he bought before much before she was born. My uncle wasn't someone caring much about his camera, the Photomic viewfinder was in a very bad shape (I had to clean it out, and recalibrate it) and the lens had a jamming aperture ring and of course a lose focusing ring.

 

I unmounted the lens, to fix the aperture ring which was easy, but the real challenge was to fix the focusing ring. Whitout repair manuals I experiemented and fixed after all, but I cannot advise you to do it yourself.

 

There was a moment when I almost gave up, as I could not assamble the two main parts of the lens (coupled by the helical focus mechanism).

The free play results from the fact (so I was told by two technicians) that the tolerances in the focusing mechanism of the lens are smoothed by grease/fat/oil which of course evaporates etc. over the years (Leica sometimes advertises that they don´t use fat because their tolerances are so small, sounds good to me, because sometimes the lubricants find their way to the glass surfaces, which is really nasty...) A service can usually cope with that. I don´t believe it seriously affects image quality.