[ATM] Stubborn Oblate Spheroid

[Jason Hissong <jhissong@gmail.com>]

Hi guys,

I am happily polishing away my 8" F4.3 BVC mirror but I have a stubborn 
oblate sphere.  I am working TOT, wide W's at about 1/3 diameter or more 
overhang back and forth and about 1/3 to 1/2 D side to side...  It still 
persists!

Picture at about 1 to 2 hours after start of polishing.  Was doing 
mostly 1/3 diameter strokes with very slight side to side:
http://www.undermidnight.com/images/atm/oblate_spheroid_1.jpg

After about 3 to 4 hours trying various things...
http://www.undermidnight.com/images/atm/oblate_spheroid_2.jpg

After about 7 hours (this was using extra weight on top of the tool) 
with the wide w strokes.:
http://www.undermidnight.com/images/atm/oblate_spheroid_3.jpg

The edge is polishing very nicely.  Still have pits to polish out.  I am 
using Standard hardness Acculap pitch.  I am ordering some medium in 
case my lap is too hard.  I press for about 45 minutes prior to 
polishing.  I admit, prior to the past couple of hours, I probably did 
not press long enough.  This time I let it press longer.  I am also 
microfaceting as well. 

Does it look like it is slowly going away (it does not look like it to 
me)?  I think my surface is looking pretty smooth.

Thanks for the advice!

Jason
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