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So I am aware that you are not supposed to drill straight down with a flat end mill, so if i did want to run drilling operations on my cnc can I simply put a regular 1/4" drill bit in my machine? (by regular I mean the classic drill bit I would normally use in my handheld drill).
I would be machining almost strictly wood, sometimes hard wood, for this specifically though it is an mdf panel.
I use short length drill bits 1/4" and smaller. For larger holes, use an endmill with a spiral ramp.
ok great thank you!
Any bit you would consider putting into your hand drill to put a hole in wood you can use in your CNC machine. Even well past 1/4". I wouldn't recommend using a basic hole saw though. No chip room.
For metals, some basic rules are bright finish for aluminum and Black Oxide for steel. Cobalt for alloy steels and stainless. TIN coating is a basic and low cost improvement you can add to most of those. 118 deg or 135 deg tip. Your choice. Won't much matter in many basic situations. 135 deg ,is more prone to lifting on breakout in thin work.
In some situations it could also be advantageous to make holes using end mills and helical interpolation.
- You can make holes of different sizes without changing the tool.
- You can "fine tune" the hole diameter if needed.
- You can make blind holes with a nice flat bottom.
- You can use a high RPM spindle (unsuitable for a large diameter drill bit).
It's hard to know what the OP means by CNC machine. Could be anything. If an actual machine tool like a 40 taper VMC, any of the suggestions so far are do-able, but if the OP is running a router type screaming high speed spindle thing, then forget my whole first paragraph posted earlier, and stick with C Of D's and ger21's ideas.
I will say a drill is about the best roughing tool out there, but the further you get past 1/2", the fewer sizes people tend to have, especially those just stating out. That's when the helical boring can save you money and trips to the tool store.
How fast do those dang router spindles go anyway? On average...
Do they tend to be fixed speed or variable with poor torque at low speed? I know nothing about them.
Yes, they have poor torque at low speeds, so larger bits may stall the spindle.
If you use a conventional drill bit just be aware of the tip geometry.You need to program to create the hole that you need after taking into account the tip angle so that the correct tip or shoulder depth is achieved.A lip and spur bit may need to have the distance from the tip to the end of the helical section taken into account and in the event of through drilling the spoilboard may gain a bit of decoration.Helical interpolation works very well and shouldn't do more than lightly brush the spoilboard.
For the benefit of the-gentlegiant-one machine I know of has a machine with a spindle capable of 24,000 rpm although it doesn't have too much torque below 8,000.
Amana Tool 51688 SC Spiral for Steel, Stainless Steel & Non Ferrous Material 5/16 D x 7/8 CH x 5/16 SHK x 2-1/2 Inch Long Spade Drill / CNC Router Bit. 118 Point Used to drill very short, shallow holes in hard (or hardened) steel. They can be used either in CNC or drill presses.