[ATM] Help me get back to sphere

["Rich Ball" <ShooterBall@hotmail.com>]

I have been attempting to bring my 8" f6 mirror back to sphere after finding
the middle too deep and the edge turned down.  I first tried a simple short
COC stroke MOT.  Things got only worse.  The numbers all got farther apart.
The edge didn't improve.   Then I tried, with great hope, Bob May's little
half stroke.  The idea of it appealed to me.  But alas, the numbers
continued to spread.  The hole is embarrassingly deep.  With stationary
light source movement of the KE is about one inch! from center to edge.

I have pressed a great deal, hot and cold.  Am I to suspect (after hours of
the above procedures) that my lap is at fault?  Would it be a reasonable
gamble to pour a new lap and start over?   Can this mirror be saved?

I don't know what to do.

Rich Ball
Oak Park

PS.  Note on my lap:  The deep lines that I cast into the pitch are long
gone.  Several times I have restored them with a saw.  But they don't last
long.  I always use a net when I press and I don't start pushing glass until
the net is taken up into the pitch.  I chamfered the edge of the pitch about
45*.  Temperatures in my work room have been near ideal lately.  Not too hot
or too cold.  (Cool spring in Chicago)
I have not chamfered the edge of the mirror.

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