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Still new to CNC, so I hope you all might help me with a real-world example. Here is an archtop tailpiece design. Assuming a 5/16" hardwood (ebony, rosewood, or cocobolo), what bit/speed/feed would you use to (a) cut the outside profile, and (b) cut the 12" radius and the spherical indents on the top? My CNC handles up to 24,000 RPM. Also, not shown in the rendering is a .080" inlay that will go around the border on the top, which is .080" from the edge. That inlay will be about 3/16" deep. What bit/speed/feed would you use to cut that inlay pocket? Thanks!

What feed rates can your machine do?
What tools have you got already?

My machine maxes out at 100 ipm. The bits I am planning to use (and have) are a 1/4" ball nose, 1/2" ball nose, and 1/4" end mill.

You should be able to run everything at full feed of 100ipm
Your quarter inch tools should be happy at 24000rpm and your half inch tools at 12000rpm.
You can slow your feed if the finish is looking a bit rough.
Experiment a bit!
Your machine feed and spindle strength (HP) and overall rigidity may be a factor but the load on the spindle at these speeds and feeds should be around 1hp.

Thanks!

I would disagree with at least the first part of this statement. While the tools will cut plenty fine at those feeds and speeds, they will dull quickly. 24krpm is on the high side for 100ipm. If 100ipm was my max, I'd probably never go above 15krpm for bits 1/4" or larger.

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