Claude Dupuis replies: I have not seen or heard of any turners using a micro bevel or as you put it a secondary bevel. A secondary bevel in my opinion is not required for both ease of sharpening and function. You want to ˝ride the bevel˝ in many cuts and if you have a micro bevel you might fine it difficult.
Jon Siegel replies: A secondary bevel may be very close to the edge, and it is called a ˝micro bevel˝. This may work on blades of hand planes, but most woodturners do not use this type of secondary bevel. You might grind two or more bevels that are equally spaced, and this gives, in effect, a convex bevel. If you grind a second or third bevel, then your grinding process is necessarily twice or three times as time consuming. Woodturners may never agree whether a bevel should be convex, concave, or flat—but I follow the middle road and use a single flat bevel.
Bob Oswald replies: You will probably get varying opinions on this. Sharpening is a religion. While honing and secondary bevels will clearly cut even finer and cleaner, in my applications the tools dull quickly enough that I don’t waste the time. A primary bevel on a power tool, for me, is more than adequate. However, on hand tools like gouges which I’ve used a lot in manual carving applications, I strop them every few minutes to keep them surgically sharp. Five minutes of hand work is a long time and re-sharpening a dull hand tool then takes more time than keeping it sharp. I spent about five hours of hand work on a violin carving recently. I never went to the stone for sharpening. I just religiously used a slip-strop and the result was incredible.
Al Breed replies: I think that when I neglect to sharpen my turning tools and a secondary bevel develops, they stop cutting well. I think that good cutting action happens in turning when the bevel is rubbing on the work, so a long bevel is good. A secondary bevel would cause the tool to be lowered to cut, reducing the contact with the bevel on the work, probably making it less stable. Bottom line is that a single bevel has always been what I’ve used and with good results. Check Frank Paine’s The Practical Woodturner and see what he says.
Dave Emerson: For the bevel on a fingernail sharpened bowl gouge, I just run it over a carborundum stone. I can resharpen this way a few times before returning it to the grindstone. My old carborundum stone has a deep groove in it! So don’t do it on a stone you want to use for anything else.