First project - Hexagonal staircase newel cap

This has been debated here a few times, and basically the conclusion always is that while surface speed matters for metalheads (and even then, mostly for those who cut something more challenging than aluminium), for wood and given the endmills typically used on a Shapeoko (nothing larger than 1/4" in 99.9% of the cases), surface speed does not really matter. Or we could say that wood is tolerant to a very wide range of surface speeds (as long as the chipload is in check)

So for RPM as far as I am concerned it boils down to “set the RPM to the highest value you can bear”. @gmack once taught me that maximizing RPM minimizes cutting forces, so maxed out RPM should be the target. But I also used to have a trim router on my machine, and could not bear the screaming sound of a Makita at 30.000RPM for very long.

DOC is a different beast, and there was not much beyond experimentation to determine what’s a good value on a Shapeoko. Folks who know their deflection math concluded that shallow DOC and fast feedrates work better on a Shapeoko than deep DOC and slower feedrates. I like to use the “50% of the cutter diameter” rule on my Shapeoko. I hear the lucky SO Pro owners get to go deeper than that.

If you can’t sleep at night, here’s a thread where we discussed the matter of how to determine feeds and speeds on a Shapeoko (spoiler alert: there is of course no definitive answer, but that thread is basically where the stuff in the ebook’s feeds and speeds chapter comes from)

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