Lots of people have trouble sharpening an incannel gouge. It is really fairly simple if you do it with a drill press and a mounted stone.
The diameter of a stone can be changed. Just put the stone
in a drill motor and spin it against a spinning grinding wheel. A smaller
diameter wheel would have worked a little better on this gouge.
First order of business is to put the stone in the
drill press and then adjust the drill press table height so that you have
the desired angle. I have this set at about 23 degrees.
You can see on the stone where you have been grinding,
and this allows you to remove the gouge to quench it and then return to
exactly the same position you were in before. This is how you control the
angle of the bevel.
Now grind the incannel bevel on the stone. The
rotational torque of the stone will move the gouge to one side, so you
have to counteract that force. Look at the bevel every now and then to
make sure you are grinding in the center.