Cheers everyone, I am now in the situation that I have to drill a hole. I bought drill bits a while ago (1mm, 1.5mm, 2mm and 3mm). I want to use the 1.5mm drill bit now to drill a 3mm deep hole through hardwood. Does anyone have parameters that work without breaking the bit? Especially RPM and Z-Speed. The rest does not matter I guess. 
Thanks a lot!
Drill bits are machined to cut down, and evacuate chips. But not cut to the side. Unlike a cnc bit, which has cutting geometry meant to cut on the sides.
Cutting a helical hole with a drill bit sounds like a hard way to do it. A 1/16" cnc bit or something would make quick work of it.
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I just want a straight hole, 3mm deep (not wide).
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My bad. I missed that.
Not got much experience drilling such small holes in wood but if it’s any help I do quite a lot of PCBs with carbide bits and would typically plunge at around 50mm/min with a 12000 rpm spindle for this diameter bit. You should be able to go quite a bit faster in wood.
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Had to take a 1mm, went with 150mm/sec. Worked well. Thanks. 
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Hey @superflyguy, curious, what PCB minimum track width and minimum clearances you’re able to reliably achieve for your MPCNC build? Cheers!
You may want to look in your CAM software for a “peck drill cycle” which, as I understand things, will go straight down a bit, come up to evacuate chips, then go down a bit further, repeating the cycle until the hole is at the assigned depth.
Oh, I have a 3018 that I’m using for this. Never tried with MPCNC …yet.
Traces start to get a bit sketchy for me when I design them for 0.4mm or less so I tend to keep things chunkier to avoid any possible frustration. 0.5mm is the finest I’d go at a push.
I’ll almost always use 0.1mm 30° V-bit and usually isolate with a two or three passes minimum.
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