Thread: Lapping--what's flat??

I got the Norton set about 2months ago and have been using it quite a bit (almost every evening), trying to get four different razors up and running.

I also have a 1/2" thick granite tile that I picked up at the HD store that I've been using on my 8k Norton and 12k Chinese stone.

Now here's the hangup. When I use the Norton flattening stone on the 4k Norton (per the included Norton DVD), it takes material off the edges. When I use the granite slab and 600# sandpaper, it takes material off of the center. We also have a 1" marble slab for kitchen use (although the finish now less than flawless in many spots). That behaves similarly to the granite tile--material comes off the center of the hone.

So I don't know which one is getting me closer to flat. I'm leaning towards the marble/granite.

What say you? Are there any easy ways to check here at home. I've got some rudimentary tools (basic woodworking, advanced reloading stuff). I