Lapping stones dead flat

[Diemaker]

Of course what I am talking about is beyond practical knife sharpening, as is most of what we talk about here, but I am trying to educate as to what is good technique. It is also a good tool for your toolbox, ie head, for when you need to get something very flat. When I have tried to flatten a steel surface with sandpaper on a surface plate I needed to hold .0002" max out of plane on a small steel block and the sandpaper wasn't working and only getting worse the more I messed with it. When I started trying to dress resin bond stones sandpaper was the first thing I tried and thought it did ok, until I tried loose abrasive. Yes we take things to extremes but that is how we learn.