Janka hardness 950-1010
American black Cherry or Black Walnut
feed speeds, end mills and speeds would be great, it will undergo finishing and eventually a polish for a high quality finish.
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Whatever the optimal values for these materials are, theyâre far beyond the SMâs limitation for power, speed, and stiffness. Wood generically works between at high feed rates, faster than can be easily hand-fed on a table saw, for example. The forces required are quite large; the SM canât do it. [Addendum for clarification: The SM canât do wood milling at the optimum speeds and feeds for the material.]
[Addendum for expansion. Any use of this machine for milling wood requires some kind of compromise. Itâs not that it canât mill wood, just that it canât do it anywhere near optimal for the material. The SM is far to weak and wobbly machine for the feeds and speed that large machines use to be relevant. Tables of good cutting parameters for large machines are available; theyâre irrelevant to the SM.]
Second best is to use a roughing pass and a finish pass. The roughing pass is to allow the finishing pass to remove as little material as possible so that you can run it at maximum-to-SM speed.
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Have to strongly disagree.
The SM is more than capable of handling hardwoods. Iâve done a lot of walnut, maple and oak. Iâve also done Zebrawood (1830 janka) and even Purpleheart (2500).
The caveat is that you canât push it that hard. So itâs slow and takes some time. As long as you have patience you can do a lot on it. If I was trying to rely on it for a business, then no, itâs not fast enough to be profitable. And yes, I am trying to figure out my next cnc machine.
Ignore any feed/speed calculators you find online. They assume that youâre using a regular cnc machine. The SM is underpowered.
I run 1/4" for clearing (stock to leave 1mm) and then everything down to .5mm for finishing passes. Iâve found that somewhere between 400-600mm with a .5mm step-down works well with a 1/4" bit. I can sometimes push it to 1mm but I tend to be conservative and leave it at .5 for all sizes. Speeds I lower slightly as bits get smaller. Spindle speed always at 12000 rpm. Only with stuff like acrylic where youâre worried about melting would I lower it.
Start slow and then you can speed up on the controller. Make sure your brackets are tight and thereâs no play in the rails or bed. Keep stuff centered as much as possible and parallel to the x-axis. Use your ears. You can quickly tell when itâs straining or chattering and need to back off.
As far as cutting deep goes you canât cut much deeper than 10-12mm (in multiple passes) where the bit is contacting on two sides like with contours/outlines. Need to clear wider if going deep.
BTW, donât even bother with Luban. Learn Fusion 360.
-S
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Thatâs a great answer, thank you. Speed maybe e my friend when using smaller steps, Iâm in a CNC programming course right now so I have a great fundamental understanding of how it works, but like you said this machine is not a commercial grade, Iâm using it for proof of concept. To produce prototypes.
Tim Minke
CEO @ LED The Way
I did not say it wouldnât handle hardwoods. What I did say is that the way it can handle them isnât anything close to optimal.
Thatâs exactly what I said. You canât push the machine to the limits of the materials ability to be cut. You can only push the cut to the limit of the machine. Focusing on the material here is a distraction. Focusing on the limit of the machine is everything.
He asked what settings he should use for specific materials on his SM. Not for the âoptimal valuesâ for milling those materials. Your reply was neither clear nor very helpful and implied that he shouldnât even really try.
-S
Iâve annotated my original post to clarify the referent of the pronoun âitâ in the passage youâve quoted. I would think it would be quite clear that itâs possible to mill wood with SM by what I said in the paragraph immediately below, but apparently not.
Hi friends,
what are your thoughts on using bits (e.g. flat-end) with a diameter of 6mm on SM? The use case would be for example multiplex or beechwood cutting out a piece of 10-20mm or creating a pocket of 5-10mm (for the pocket rather a roughing pass not a finishing pass).
Which settings would you select for Speed and Step-down? (I am usually starting super-conservative with 100mm speed and 0,5mm stepdown, spindle 12k)
Thank you very much,
H.
P.S.: As you are commenting that the tables in the internet are not applicable to SM - would be great to maybe have a library here with the respective information for Snapmaker.
Look through the forums, there is a lot of info in here. SDJ has answered some of what you asked before here: