So they are stamped (or cut) from a bar, and the flat surface that "drifts" on the mandrel is rough with all traces of shear (what the product photo is suspiciously free ). I believe that with a good hit they will work well, especially if they are lubricated. Or of course it would also be possible to put them on a grinding machine and finish the surface yourself - but why? A similar set from Grizzly costs about the same and comes well sharpened and ready to use.