I have also incorporated this idea with ball end mills when a 0.250-in. round shape was needed. • To mark 0, 90, 180, and 270 increments on round stock in a lathe for indexing. I stopped the lathe and opened its drive cover. In AutoCad I drew a circle with 1-degree increments, printed it out, and attached it to the toolholder.
• For old lathes without trav-a-dials or digital readout, I make dial rings that go over saddle cranks. If one revolution of the saddle one inch, I divide the ring into an inch by marking it at every 0.01 in. or 0.005 in. so I can use the cutting tool to scribe a line in the part at any angle. • When turning brass or bronze, I keep the small chips from flying back at me using a piece of thin shim stock as a shield.
I cut the shim stock to the appropriate size, put it behind the insert and bolt it to the main drive hub using double-sided tape. I made a pointer that points to the label, and now when I’m finish turning, I can use the cutting tool upside down and reverse the machine’s headstock and tailstock, then bring the tailstock up to where the centers almost touch (tailstock retracted most of the way).
Be careful not to bang the centers together. Clamp down the tailstock out until the razor blade is caught gently between centers. If the centers are off, the razor blade will be at an angle, and it is easy to see which way to adjust. If they are centered, the razor blade vertically between centers, spinning the tailstock and hold a single-edge razor blade will be oriented square between the chuck jaws and workpiece.
I’ve found that I can clamp down fairly hard on these shims and still not damage workpiece surface finishes. • Follow these steps to make your