From what I can see in the pic is that the split point is not stopping at the edge of your wheel. It appears the the secondary relief, to be going past center. You need a sharp corner(possibly even a slight dovetail) on the wheel edge that ends at the web center and a stop set(if you are using the table to travel in towards the center) so that another cutting edge is created there. What you end up with is a bit of negative rake on the root of the opposite primary flute?
I've always done the same edge by hand on a bench grinder. Although I do use a 3/4" wheel and cut a step into the right side to obtain 2 sharp corners to split the point and add the secondary relief at the same time.
If you set the 59 or 70 deg and index the drill 180 to cut both flutes, then reset to get your seconday relief and use the same index, it should all work without to much trouble. Maybe more trouble than by hand, but much more accurate.
Now that I look at it, my methods are for a split point. Not a chisel point as shown. That style may over run center. Hmmmm!
Buy a bit and see if you can duplicate all of its angles?
DC
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