some of the edges are convexed, I'm not sure about the d mutt, but I think my yardkeeper and DFLE are. you can sharpen just whatever agle it's at, (by hand with a stone) at the very end of the edge, hold the stone at a sharp angle to the edge. if you're sharpening like a regular flat ground edge, whatever angle you prefer. but you're going to change the edge entirley.
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and if you want to keep the convex edge, you can use the sandpaper and mousepad techniqe.

and welcome to the scrapyard forum!!!
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