[Paraquat]

I had a passing thought the other day...

I just started using an Ingersoll 1.25" inserted drill that we had purchased for our shop lathe, but I used it in a mill to punch out an inside diameter. It ended up saving 2 minutes per part by drilling through where once we circle interpolated.

So this got me wondering if there was any savings as far as cycle time or tool life if I were to pre drill the profile of a part before milling the profile or would the interrupted cut beat on the tool and negate any savings. Confused? Yea, a picture is worth a thousand words...

I'm attaching two pictures. One is a part I have to make. If memory serves it's roughly a 2x3 post on a 4x6 plate of 6061.

The process, as of now, is to rip the profile with a 2.5" diameter face mill with a 6" extension, then we come in with a finish mill to clean it up nice.

I want to know if there's any benefit to drilling the outside of the profile to relieve material; if I could accelerate the material remove rate (buzzword of the day, rolling my eyes), or if that interrupted cut would beat on the inserts too badly.

[Jim Dawson]

While a drill is the most efficient method of hole making, I don't think it would provide any gain in the instance you show above, think about the tool path required to take advantage of the drilled holes. I do however sometimes rough out a profile on the bandsaw prior to milling to save some time, if I have a lot of material to remove.

[metalmayhem]

I've used flat bottom insert drills many times to hog out large pockets and they are extremely efficient . The nice thing about them is that they can clear a pocket similar to a plunge mill , vs a pointed drill which creates a block with a bunch of holes in it . Usually thats for heavy steel jobs though .
Check out some of the auger mills iscar has , they are super efficient hoggers on aluminum