Translating Total Feed Rate to A Axis RPMs and X/Y axis Feed Rates

**rgsparber** · Nov 3, 2015, 10:57 AM

If you are not into CNC, this article may make no sense to you at all. Actually, if you are into CNC, it still might not make much sense

This article explains how to take the feed rate for a cutter and translate it into the correct RPM for rotating an A axis plus the correct X axis feed rate that gets you the desired radial depth of cut.

If you are interested, please see

http://rick.sparber.org/TTFR.pdf

Your comments are welcome. All of us are smarter than any one of us.

**Paul Jones** · Nov 3, 2015, 01:34 PM

Rick,
Yes, it makes sense based on your conceptual analysis by first considering cutting around the A-axis even if the tool was stationary in the X-axis. Also makes sense looking at the problem from the vector sum and preventing the milling cutter from cutting a helix (although this will be an ideal application for your setup).
Thank you for the article, Paul

**rgsparber** · Nov 3, 2015, 05:59 PM

Paul,

The best way to cut a helix is to index the A axis. Something like G1 F3 X1 A360 would give you 1 TPI I think.

Rick

**DIYer** · Nov 5, 2015, 03:22 AM

Thanks Rick! We've added your CNC Feed Rate Translation Method to our CNC category, as well as to your builder page: Rick Sparber's Homemade Tools. Your receipt:

CNC Feed Rate Translation Method by Rick Sparber

tags: CNC