Hey Jerry, I do them the width of my table saw blade and made a jig to run them right down the middle. Not much of a jig really, just set the table saw height to however deep you want the insert, set your fence and run a piece of scrap hardwood through. I like stuff that's about the size of 2x4 maybe six inches long. Then, get an 11/32 drill and drill a hole through the center of the kerf. Helps to drill a smaller pilot hole first. Also, need a zero clearance insert on the table saw. All you've got to do is line up the grain to cut it the way you want, put the shaft in the pilot hole, set the scrap up against the fence and run it through.
That clear as mud? If so, give me a holler and we can do them down in my shop sometime
Stan
Forgot to say, I've also had luck using hardwood dowels that are 1/8th inch as pins right below the self nock as well. Really easy, just drill a hole and glue in the dowel.