Drilling on Nomad - Is this normal?

CNC Machines Nomad
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In the video below you can see me drilling 2.2mm holes on a 4mm steel pin on the Nomad

Is that kind of noise expected when drilling? You can probably also see some smoke coming out at the end

I’m drilling at 5,000 rpm, Z feed: 25 mm/min (1 in/min), peck drilling at 0.2 mm. I added some water before starting to drill.

Is the noise/smoke an indication that I need to slow down the rpm?

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I’m no expert but 5000RPM in steel with a 2.2mm drill bit sounds about twice as fast as it should ideally be? so probably “yes” to your question, but I’m sure Nomad owners who actually know what they are talking about will comment.

Also, for coolant I would use WD40 or a mix of water and alcohol, or even an air blast, rather than just water.

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your Feed Per Rev is too slow and SFM is too high. Smoke is an indication of excess heat due to rubbing and not creating a good chip. Instead of water, use something that has a lubrication quality and try to create a workholding solution that is more rigid.

Also I suggest trying cobalt drills if you have any on hand. They seem to take a good amount more abuse than regular hss in harder materials

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Do you have any references for feeds and speeds with that particular drill bit? Or do you have any details on it?

Do you have any more information about the particular steel used for the pin?

Without them, comparing to cutting conditions for a solid carbide twist drill:

  • 5000 RPM: 34m/min surface speed seems a bit low unless you’re working with a harder steel.
  • Z feed: 25 mm/min (1 in/min): 25mm/min at 5000 RPM is only 5µm per revolution, you should be looking at more like 30µm per revolution at least. With feed per rev so low, your drill bit is probably rubbing more than it’s cutting, leading to friction and heat.
  • peck drilling at 0.2 mm: The purpose of the peck is to let chips clear so I think you can increase it pretty substantially.
  • I added some water before starting to drill: I’d use real cutting fluid instead of water. Water isn’t a great lubricant and a good lubricant really makes a huge difference when it comes to drilling. Seriously, even with my drill press, cutting without lubricant is like wading through mud while cutting with cutting fluid is like cutting through butter.

But to set expectations, even with a much more powerful spindle than the stock Nomad has, I haven’t had much luck with drilling. It requires a lot of axial rigidity on the Z-axis which on the 883 Pro at least seems lacking.

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Agree with all of that.

On my Shapeoko drilling 6083T6 Aluminium with a 2.2kW spindle I get vibration if I go much over 5mm drill size with carbide spot drills, that’s with lubricant.

The main issue, as Vince and Lucas say, is the downward force you need to keep a decent chip size and let the drill actually drill.

I also note that the workpiece is wobbling around quite a bit which won’t be helping and would likely break a carbide or similarly hard drill.

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All mentioned above could be the issue but after what I saw in the vid it could be a dull bit.

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