Drilling Deep Holes in White Oak

Advice on CNC settings for drilling holes in hardwood. May 20, 2009

Question
I have a ton of holes to drill through the edges of white oak boards, 5/16 diameter and 5" deep. I have the throw to do it in Z on the CNC with no problem. I am looking for recommendations for tooling, feed and speed, as well as an optimum peck depth to use as a starting point. Any suggestions? I am looking at an 8" WL fuller 25300312 Bradpoint in an SYOZ25 collet to begin with, but am wide open to suggestions.

Forum Responses
(CNC Forum)
From contributor R:
Your big problem is friction and burning. Keep the RPM low (600 if possible) and the feed a bit high, maybe 60 to 100 IPM to start. Being 5/16, you can probably peck about 1/2" at a time. These parameters should get you started, feel free to change them as needed. Keep the rise above the material to a minimum to minimize the time.

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From the original questioner:
I know my spindle goes as low as 1000, I will make an experiment and see if I can get to 600, never had an occasion to go so low.

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From the original questioner:
Just in case anyone is interested, here are the final results. 5/16 HSS brad point bit at 3000 RPM, 225 feed and peck of 1.25". Definitely generated some heat, but made the sacrifice for some more speed. Wax on the drill bit occasionally made a great deal of difference.

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From contributor R:
Glad to hear it worked out. Using HSS was a good choice. It certainly is much more tolerant to heat than carbide is. I am ashamed that I didn't mention that in my original post.