Unfortunately, many people stay away from such grinds because they can be difficult to sharpen. Unlike a single, or double bevel grind, you can’t just lay down the edge on a sharpening stone, and move it back and forth, because the side of the blade is curved.
There are different methods of sharpening a convex edge, including using a pad with fine sand paper, but I have found all such methods to be too impractical for field sharpening. In the end, no such equipment is necessary. A convex edge can be sharpened using a regular sharpening stone in the exact same way that you would use it to sharpen an axe (many axes having a convex edge).
I use a small sharpening stone, the Fallkniven DC4, which I carry in my possibles pouch.
To use it, simply take the blade and hold it in front of you. Now take the stone and place it so it touches the edge of the blade. By holding the edge of the blade up, you can see if the stone is touching the edge. Now begin to move the stone in a circular motion along the blade.
Then reverse the blade, so you can still see the edge, but are now sharpening the other side. If you wish, you can count the number of circles you make with the stone to insure that the grinding is even.
Keep in mind that for most sharpening you will only be using a fine stone. To get a hard steel like VG10 to be razor sharp, you will have to spend a good amount of time sharpening, so do not be discouraged if it is not shaving sharp after a few passes. Because the stone I use is so short it may take 80-100 circular motions on each side of the blade to get it shaving sharp.
