By convex do you mean, instead of a straight taper, a bit "bowed" out, or rounded? Ha...
As for the belly of the bow, for the tiller, can it be flat? Meaning, not rounded but straight across? I have seen several people do this, but read others recommend that you round it...
Update: What do you think of 15" no taper (at 2" wide) after fades and 15" either straight or convex taper to .5" nocks? Also, looking at the bow from the side, what sort of taper are we looking for here? What about 11/18" at the fade to 3/8" at the nock? Can the belly tiller be flat instead of rounded? Also, must the fades, if looking at the handle from the side, be consistent without any deviation on both sides of the handle? By this I mean if my handle is 1 3/4" deep at both the top and bottom, with a custom grip in between, must the 1 3/4" deep handle turn into the 11/18" limb in a space of 2 1/2" along a straight angle, or can there be a little bit of a concave curve in there due to the shaping of the handle?
In addition, what do you guys think of Tung Oil for a finish?