ATM %$^%##%!! Rings won't smooth

[richas@pacbell.net]

I am polishing my second mirror a six inch.  I have it spherical and 
ridded it of a slight TDE.  I have concentric rings which I cannot 
polish out.  I have hot pressed my lap seveeral times and also 
pressed in a pattern with some screen type material.  I am polishing 
MOT with a one inch overhang.  I have varied the stroke longer and 
shorter.  I have varied the pressure from light to very hard.
             My next step is to make a new lap.  I am using willman Bell 
pitch.  I softed the last batch as I could not press ANY dent into it 
with a fingernail.  I may have made it too soft as I have had to trim 
the lap often.  I think For the next batch I will not soften it at 
all or only slightly. Could these rings be caused by the end of the 
polishing strokes?  They may correspond to the end radius of the 
various strokes I have used.
        Any ideas would be appreciated.  I am tired of working on this 
little mirror.


Rich