Question about 1/16 upcut feed and speed

Hello, I am new on CNC and I want to start using a tiny 1/16 upcut bit to do fine texting on oak. Does anyone has a recommendation about what would be the best settings?
I tried setting the makita at 4, with a feed rate of 80 and a plunge rate of 45 and I broke one immediately. After reading more I understand now that I had no idea what I was doing, while the 1/8 bit was working just fine under those settings. I am a little overwhelmed by the amount of information that takes to calculate the appropiate speeds and feeds. Can anyone share a recommendation?

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See if you can find the manufacturer notes for optimal feeds and speeds for that particular bit

80 IPM is too aggressive for this tiny bit. Also, the 45 plunge rate is very aggressive as well. Try it between 40-50 IPM and then the plunge rate around 20-25. Additionally, it also depends on the Depth of Cut (DOC). To be on the safe side, the DOC should not be more than half half the diameter of the bit. So if you are using 1/16th inch bit, the DOC shouldn’t be more than .03 - .04. If you maintain this DOC, you can probably push the bit little faster.

Edited to correct the numerical values


To be on the safe side, the DOC should not be more than half half the diameter of the bit.

Do you mean half the diameter? So 1/32 deep or .031?

Yes, that is correct. I mistyped. It should read .03-.04, not .3-.4.


I use a 1/16 - 425-DNC062 Bits & Bits with spindle speed of 16K Feed Rate of 50 IPM and Plunge rate of 20 IPM, Pass depth of 0.0313, Step over 0.025 with oak all the time. I have not had any problems.


As a rough rule of thumb I go to Amana’s website and find their version of the bit and start with what they recommend. It’s not perfect but I have never broken a bit following their specs.


Thanks all for your kindness on sharing your comments. I will give it a try and let you know how it goes!