I re-profiled this DMDC for a Dog in Cz who had difficulty getting one...the edge at the start was 30 degrees or so...I reprofiled the primary edge to 23 degrees and the secondary bevel to 20 degrees giving him a robust tapering edge which could still be very sharp. These angles are about ideal...a Sharpmaker will give a primary angle of 20 degrees and a secondary one of 15 degrees...a bit more suited for pen knife use IMO...or knives with a high Rc heat treatment which are designed as slicers...a chopper benefits from a bit more meat in the blade edge...I like a 23 degree convexed edge the best...and after practise tapering in edges done on my Lansky system on the belt sander to a proper convex edge using a marker pen to colour the edge so I knew what angle to hold the knife to the belt sander ( trial and error here but the removal of the Ink gives a good idea ) now enables me to do a good edge straight off freehand.