The Spyderco Sharpmaker is almost the sine qua non of knife-sharpening equipment. If you’re one of the 75-percenters who reach for the Sharpmaker when your knife loses its edge, you know that Spyderco recommends a 30-degree inclusive back bevel and a 40-degree inclusive microbevel.
Some knives aren’t terribly well suited to the Sharpmaker treatment. Emerson knives are all chisel-ground, and a hamhanded owner can quickly ruin one with a Sharpmaker. Scandinavian-grind knives like Moras or Marttinis were traditionally profiled with edge angles tighter than 20 degrees inclusive, although most newly-made Moras are given a slightly more obtuse microbevel for better edge retention.
Most steels can take a sharper edge than 40 degrees, but not all of them can keep that edge in regular use. I couldn’t believe how fine an edge the S30V Sebenza took (and held) but some steels and some applications require a 45 degree grind.
So I ask you, do you 30 degrees? Or, if you use a Sharpmaker, do you stick with the microbevel?