Anyone this aggressive with CNC?

I just read the Artisan tool heads article and posted a comment asking how the power increase of the 200W CNC would actually equate to real world application.

I saw this footnote afterwards:

[1] The max. recommended feed speed for 50W CNC Module is 1000 mm/min, with 1 mm step down, and 3000 mm/min for 200W CNC Module, with 2 mm step down.

Does anyone actually do stepdowns of 1 mm regularly up to or close to 1000mm/min?

My standard stepdowns for 1mm, 3.175mm end mills and my vbits is 0.5mm at a speed around 400mm/min.

I have a 6.35mm end mill I will occasionally do 0.8mm stepdowns but 1mm always sounds sketch (unless I should adjust the speed on this, still around 400).

Iā€™d be so paranoid to try their footnote recommendations and yet the lure of increasing my work speed now looms mighty tempting.

What say you all? Depends on bit? What other factors? Who has been that brave and in what wood types?

Depends upon the hardness of the wood.
With hardwoods like oak, maple, walnut etc. .5mm and 600mm/min is as fast as I usually am able to go and a lot of the time only 400. Any time Iā€™ve tried to do much more than that Iā€™ve ended up with play in the x-axis. With softwoods like pine I could probably push to 1000 but since I was first playing around I havenā€™t done any soft.

Iā€™d be surprised if the Artisan can actually go that fast at 2mm step down, but I donā€™t think itā€™s out of the realm of possibility. Might just be overly optimistic/best case scenario.
But even if it can only do 1000mm at a 2mm step-down, thatā€™s still ~6x faster than the 2.0.

Luban is still the weak link and needs to be drastically improved to take advantage of the Artisan. Until then Fusion 360 is a necessity.
-S

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Iā€™ve been a bit aggressive with mine, I have a ā€œlastā€ generation A350. (Before the new rails, but with the new 3DP toolhead and square bed frame). Iā€™ve ran a 3.175mm flat end @ 1000mm/m, 0.5mm stepdown for most all of my roughing in poplar, cherry, maple (mostly maple), and red oak. My finish passes are done at 300-400mm/m usually with a tapered ball. Iā€™ve had very pretty results, however, I canā€™t say Iā€™ve done anything requiring dimensional accuracy, so I canā€™t say if my aggressive roughing has harmed accuracy. Though my finishing pass has always ended up being clean.

Deeper cuts, Iā€™ve done 600mm/m @ 1mm stepdown, but that feels and sounds a bit sketch, so I donā€™t like doing that. Another side note with the above speeds, while itā€™s ā€œfineā€ at full stepover, I usually like to do only 2mm stepovers, gives a bit better finish even on the roughing pass.

EDIT: I will say I have also done 1000mm/m @ 1mm step and 2mm step and it didnā€™t seem to drop RPM, but it does sound fairly nasty. Iā€™ll try to do more tests in the future, my life is just a bit of a jumble currently. :upside_down_face:

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I just purchased a 1mm by 17 mm reach bit with 3 flutes. Iā€™ve read 3 flutes usually requires faster speeds but its also only 1 mm cutting shaft. Would either of you go beyond 400mm/min if I were doing 0.5 mm stepdowns? The woods Iā€™ll be cutting are walnut and mahogany, just contour cuts.

And Fusion is my go to, I havenā€™t ever touched Lubanā€™s CNC side except to look at it once. You were pretty much my early guiding star SDJ and I am forever grateful for the time you took on my early threads.

Itā€™s pretty easy to snap the smaller bits like that.
So it mostly depends on whether you care if you lose some bits. I usually keep it at 400 or sometimes down to 300.

Also Iā€™ve found adaptive clearing gets too aggressive and had more problems with it killing bits. I use pocket.

Generally 3 and 4 flute are used for metals.
Only need 2 flute for wood. Single flute only for clearing passes.

-S

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Thanks SDJ,

I did order a 2 flute one as well thatā€™s at least 15 mm reach but still waiting on that. Iā€™d prefer not to break this so Iā€™ll do a light test pass or two to see how it does.

If I were trying to match the same feed per tooth of my 2 flute bits at 400 the speed required is 600, but I still have my worries of a small bit at that speed so may not go that high.

I havenā€™t lost a bit in a while so Iā€™d like to keep that streak going :crossed_fingers:.

Just my 2 cents : I have always been running my jobs rather fast and have always given preference to speed vs depth of cut. Except for finishing passes which I do slower.

Just like @Skreelink

Usually I create my jobs with relative slow speeds. And then I speed up by increasing the speed on the touch screen for as long as I feel comfortable. (and thatā€™s gut feeling based on the sound)

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Well, lesson learned in the aftermath. Bit started fine but did ultimately break, Iā€™m pretty sure due to the very shallow cutting edge not clearing enough of the dust (only 1.5 mm of the 17 mm reach was cutting edges, and as SDJ said, thatā€™s because it was really meant for metal). I think the speed was fine at 600 mm from what I observed but it could have been the combination of that and the dust.

Switched back to my tried and true 1.5 mm bit : /. Looks like the second bit I had ordered like first that broke will be reserved for more appropriate applications.

Thanks for this recommendation. I am working on some chess pieces in walnut and maple and had been running it pretty aggressively, and getting ragged finish and a lot of play in the X axis, in fact looked like the whole module was jerking around at times. I have gone back to more moderate cutting, but note I am still getting some play and layered cutting that requires a lot of lathe finishing afterwards. Is it possible I may have damaged something internally or knocked something loose? If so, where should I look to re-tightenā€¦or do you think I am looking at replacing the module?

-S