What grit(s) sandpaper to flatten Arkansas stones?

[Bruno Frontera dela Cruz]

I have now gone through 3 different stones, from two different vendors...the definition of flat must somehow be highly subjective. I bought a granite surface plate to flatten the stones on (soft Arkansas and hard black surgical) but need to know what grit sandpaper to start and finish with.Any thoughts?Thx!

[Chris Griggs]

Very coarse - I've used a 55 grit zirconia sanding belt. That's pretty coarse, 80-100 grit might be better? Use a sanding belt though -- in my limited experience oil stones will destroy regular sandpaper before it has a chance to do any flattening. YMMV...

[David Weaver]

I agree - I obliterated very coarse PSA al-ox that I had near worn out lapping plane bottoms. Seemed like a good time to use it, but a black arkansas probably would've gone through 3 3-foot long strips of it to get totally flat.

The abrasive in the paper is harder than novaculite, but I think you can still fracture it with the stones.

Light cut on a power belt sander is probably better to do the rough work (and outside and definitely with a dust mask).

[george wilson]

As I have mentioned a few times,I have flattened black Arkansas stones in a few minutes on the side of an old fashioned sandstone grinding wheel. The wheel was not rotating,just laid on its side. Works remarkably well. Use water.

[Zach Dillinger]

I've flattened mine on my concrete shop floor. Works well.