If you have a flat after finishing, then you need to "set up" the edge prior to sharpening. Most folks do this with 220 grit belt, or a 400 grit belt, depending on preference. I personally think that many makers do not pay enough attention to the finished edge of a blade. I've seen the gambit from an edge that was finished out with a 220 belt, to stropped and polished edges.
One thing that is often unrealized is that the way a knife cuts, is very dependent on the TYPE of finished edge the maker places on it. The larger and more obtuse the edge bevels, the more cutting resistance, and in some extreme cases a blade that can shave hair seems dull in routine use because of large/obtuse edge bevels. On my forged blades I strive to create as close to a zero edge bevel as possible on the finished blade. I do this by taking the master bevels down to sharp, or very nearly sharp during finish grinding.
The next thing that has to be considered is the final edge. If you use a worn 400 grit belt, then buff the edge, you'll end up with an edge that will pop hairs off your arm, but that's not necessarily the best edge to place on a knife that will be used. That "razor" edge will dull very rapidly during normal use. For what I call a "Using Edge", I sharpen with a fine India Stone. This creates a "bitey" edge, that may not pop hairs, but is much better suited to normal cutting chores that a knife will encounter. This edge tends to last much longer than a "razor" edge, and I think it's superior for things like camp chores or working on game animals. This type of edge can also be achieved by sharpening on a worn 400 grit belt, but NOT buffing or stropping afterward.
I get pretty intense on this detail about knives because I've watched over the years as people have complained to me about one knife or the other not holding an edge. After handling/examining a number of these knives, its not the edge sharpness that was at fault, but rather the edge geometry...most of those knives that people complained about had huge, very obtuse edge bevels, that created serious cutting resistance, making what was an otherwise sharp blade, SEEM dull during use.
One of the most frustrating things for a knife owner, is not being able to sharpen the custom knife they purchased....and it all comes back to how much attention and experimentation the maker put into putting that final edge on the knife. I think far too often some makers miss what they consider to be minor details, that are in fact major issues for the end user.
