Constructing and bevelling a pie-slice The picture shows what I'm trying to make.
I'm planning to use 12 of these rotated to make a 12-petal circle.



I've done this by starting with a pancake-like cylinder, than creating a triangular wedge, extruding that also, using boolean AND modifier. This gives a sector, like a slice of pizza. Then I do boolean EXCLUDE with a small cylinder to cut out the hole at the tip.

Finally I bevel the edges.
But the bevelling is not working:



I can't figure out how to do this cleanly.

Maybe I could start with a cone with MIN_RADIUS, MAX_RADIUS and depth 0, to create an anulus.  Then I could BOOLEAN AND it with a wedge.

Or even better, manually link up a subset of the generated vertices, to produce the shape.

Then extrude, and bevel.

Can anyone see a better way? And how to gain control over the bevelling process? Does anyone have a suitable link they could post?

Is BEVEL the best way to round the edges?

Finally, is there some way I could emboss the edges, if that's the right word?  Bring them out to give definitions of the object?  This may look better than bevelling.
I guess that the Boolean operations created some geometry that the Bevel Modifier can't handle as you expect. 

If you create the mesh starting with a plane like so:



and use the Spin Tool Alt-R while in Edit Mode
(Note that the position of the 3D cursor and selected view (Top/Ortho) is important.)



The Bevel modifier works fine: