From: "Bob May" 
To: "atmlist" 
Reply-To: "Bob May" 


The TOT method is more of the variety of doing chordal strokes to wear down
the outside of the surface, doing the opposite of what is normally done.
You can also do subdiameter laps and do a bit on the center and a bit on
the edge and get all of the way there by that method. The professionals do
subdiameter laps and selective polishing of areas to bring their huge
mirrors into shape.  Please note tho that they do have a bit of dogbuscuit
from such operations as the laps don't exactly polish just the high spots. 
You can see this in the final results where the shape has all kinds of
little burbles and spots in it. Bob May
http://nav.to/bobmay
bobmay{at}nethere.com
NEW! http://bobmay.astronomy.net

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