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Well the solution is the same, Rolling X. Roll down on the concave side, heel off the stone, and up on the convex side, so that the edge is on the stone as pressure is rolled from the heel to the...

Are you talking about the edge, it is curved, not straight when you put the edge on a flat surface?

If so, that is a smiling or frowning edge (the middle is higher than the heel and toe).

A...