The Lansky 4-rod Turn Box Crock Stick Sharpener works really well for me. You have to get used to it, but it works very well for recurves. You have to keep the tangent line of the point on the blade that is currently touching the rod parallel to the ground at all times (or as close to as you can manage) if you want to maintain a consistent angle.
If you want different angles than the holes in the Lansky kit provide, you can just drill holes at whatever angle you want in a 2x4 with a 5/16" drill bit or end mill in a drill press.