We are running a job from 1.0†12L14 square stock on our Y-axis lathe. The part ends up with a square flange in between two turned diameters. The square has a toleranced corner break on both sides of the square all the way around. We are milling it using a pointed end mill at 20 IPM. It takes 30 seconds which is killing us. Is there a better way?
Shop Doc Forum » CNC Swiss
Milling problem using pointed end mill at 20 IPM. Cycle time too long.
(2 posts) (2 voices)-
Posted 2 years ago #
-
Yes, there is a better way. Have you ever seen an old shaper machine? They cut metal by a ram pushing a fixed tool across the work, shaving the metal off. You can use the same principle to put in your corner breaks. Put a tool with a 45 degree leading edge in a turning holder. Position it above the workpiece using the Y-axis, then feed it down along the Y-axis shaving in the corner break. In 12L14 you can feed as fast as 300 FPM or 3,600 inches per minute.
I doubt your lathe is capable of such speeds, so let’s use 300 inches per minute for a feed rate. At 1.2 inches per pass, two passes per side, and eight sides total, I come up with 19.2 inches total feed distance.
If you take 19.2 inches and divide by 300 IPM you get 0.064 minutes or 3.84 seconds. If you have an additional 8 seconds of idle time for Y- and C-axis positioning, you are looking at roughly 12 seconds total time for a savings of 18 seconds. Plus, the tool is a whole lot less expensive than a carbide pointed end mill. When the edge dulls, offset the X- and Z-axis by an amount slightly greater than the corner break to bring up a fresh edge.
Posted 2 years ago #
Reply
You must log in to post.
