[ATM] my ongoing war story (polishing and figuring)

["Rodney Mayes" <rgmayes@bellsouth.net>]

Still at it on my first mirror.  It has now officially become personal.  After finally achieving a nicely polished spherical surface, I took the plunge into figuring.  I plunged right in to the hill of no return; well, almost.  I cold pressed for about an hour then began the Tex "normal" parabolising stroke.  Worked for about 30 minutes (slowly, carefully, randomly turning, fairly concentrated Cerox) then tested.  Found out that I had developed a central hill.  Thats right, a central hill while parabolising.  I would not have thought it possible to do this.  Still not sure how that happened.  Maybe I should have warm pressed first?  Cold pressed again.  Then I decided to use the Tex "deepening the center" stroke while parabolising hoping to get rid of the central hill.  Didn't happen.  While fighting the central hill another strange and frustrating error reared its ugly head.  I began to notice mild astigmatism in the ronchi bands.  Stopped right there!  Back to a sphere I go.  So far I have polished about 2 hours alternating MOT/TOT and using varying strokes both W and COC.  I am definitely on the right track (backwards unfortunately).  I am almost back to a nice sphere with only a hint of a central hill and a hint of a outer zone left over from my failed parabolising session.  Astigmatism is almost if not totally nonexistent.  Will have to monitor this closely.  I tthink a hour or two more will get me back to the future:). 

I would appreciate any good advice that any of you good folks would care to offer on the figuring process.  I am using a full sized lap that is beveled just enough to make the lap about 1/10 inch smaller diameter than the mirror.  Since this is my first try, I am a little unsure of the parabolising stroke length, amount of pressure, stroke speed, how much to turn while stroking, etc.  I just try to be random, follow the info that I have available, and learn as I go.  

Anyone know of any videos available that details the figuring process?  I was hoping the stellafane web page would have the figuring pages done by now but it hasn't happened yet.  Great, great web pages though.  Clear skies!
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