Silvan responds:

I'm worried about flatness because I also use my bench for gluing, say,
chess boards together. That granite thing seemed to do it though. No
feeler gauges or anything, just making sure a piece of granite
approximately the size of 1/3 sheet of sandpaper doesn't rock anywhere on
the bench.

Grizzly has a no-ledge 24"x24" chunk of granite accurate to within .00015".
That ought to do it for you. By the time it arrives, you'll have laid out
something close to $230, and you'd best have braced your bench to take its 234
pounds. You'll also need a couple helpers to get it ON the bench.


Charlie Self
"One of the common denominators I have found is that expectations rise above
that which is expected." George W. Bush