I make my router bits for parallel barrels out of a spade (paddle) drill bit. Grind the point off and then 45 deg grind the right angles. The secret (for me) is to make it slightly oversize and then try it on a scrap chunk of wood. Take off a little more where needed. I have made two, one for 13/16" and one for 1". All you need is a bench grinder and some patience. It is not rocket science.Just read an article by Fred Stutzenberger about grinding router bits to rough out barrel channels. Anybody know if these are ground by hand and eye, or is a machine involved?
I was waiting for my truck today at the dealership (issues related to a recall which they serviced a week or so ago) and I read 8 or 9 of Fred's "tips and tricks" articles. They're geared more toward the beginner (gladly I'm starting to see myself as slightly advanced beyond the beginner stage), but they were pretty interesting and helpful.Black Powder 411.com tips with fred stutzenberger part 7.