[ATM] rough-grinding - sagitta too deep

["West, Bill AED" <bill.west@mtuusa.com>]

Hello ATMers...

I am a first-timer, and I have a procedural question. I've gone too deep
roughing out an 8" - my intent is an f/6, and I currently have an apparent
ROC of about 90" (target 96"). Currently working with #120 carbo, since I
ran out of #80.

I tried 1/3 COC TOT for a while (4 hours) and got nowhere. In the archives I
saw someone in a similar situation was advised to switch to a longer,
narrow-W TOT in order to bring the edge down more quickly and increase ROC.
This seems to be working - 15 wets got me about 1/2" longer ROC. Still seems
pretty slow, but I guess maybe that's just because of the #120, or maybe I'm
not leaning into it enough. 

The main question - once I've gotten my sag to the desired depth, what
stroke should I switch to in order to regain spherical figure and maintain
my FL? I'm guessing I'd do about 75% TOT, 25% MOT, 1/5-1/4 COC. Is this
correct?

Thanks

Bill



-----Original Message-----
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Sent: Monday, June 14, 2004 10:32 AM
To: bill.west@mtuusa.com
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