Re: ATM Grinding Grit

[David McCarter <mccarterd@claven.fanshawec.on.ca>]

>But gone through almost a lb. of #40 grit so far and I've only reached
>about .030 sag. in about 5 hrs grinding.  I'm using 40 lbs. of weight

I'll bet your glass is getting thinner by the stroke. You don't say what
stroke you are using, but for digging out the center of the disk you need
to use a cordal stroke that puts the edge of the tool onto the center of
the disk. The one third center over center is not what you want at this stage.

Dave