Here I am re-sharpening one of those cheap Chi-Com carbide tipped boring bars. Now I know the reason that I kept all of the ones that chipped. I am using a diamond cup wheel for the carbide. Actually, they are probably better than new, I'll see how long they last. I spent a couple of hours re-sharpening about 18 of them. Some were pretty badly chipped on the tip.
Later, after this, I used the lathe bit fixture to re-sharpen some external threading bits, and was going to sharpen an internal thread tool that I made previously by hand grinding a point on one of these boring bars. I discovered I could not obtain proper clearance to get at both sides of the point, using the 180 DA collet holder. The ER20 holder will work just fine however.
