Question on Carbide Create "spindle speeds"

I have measured the rotation speeds for my Dewalt router and the range is approximately 15,500 RPM to 28,800 RPM.
This agrees to what Will sent to me earlier.

I have noticed that Carbide Create recommends spindle speeds that are generally all below 15,000 RPM.
So, uh, seriously…what is the use of these “recommended” speeds? Seems like all the wood I cut goes just fine at about 22,000 RPM (~4-1/2 on the router). How can I tell I need to go faster or slower? My downfeed rates are always 30 or less.

CC was probably built around the Nomad and then the Shapeoko came later. The Nomad spindle only goes up to 10,000 rpm. Unless you have your router connected to a SuperPID or some other form of gcode control, it doesn’t matter what CC spindle speeds are set at. There’s a program called GWizard that is good for determining speeds and feeds for various bits and materials. I’ve found that I get good cuts with 1/4" bits in everything I’ve tried so far at the lowest setting (around 16,000 rpm). The Dewalt router has closed loop rpm feedback control so it will maintain the rpm setting for most loads.

I posted a thread showing how to run the speed control for the Dewalt router externally. That allows you to easily adjust the speed realtime outside of an enclosure while the router is cutting to see how different speeds affect the cut. Sometimes a part will have resonance at the recommended spindle speed so I’ll turn the speed up or down until the resonance is minimized.

Thanks Tony! I would like to get GWizard but since I retired last year, I really don’t want to have anymore bills coming in for stuff I can live without. Sad but true. It does look great however!!!

I did consider external speed control (bought something on Amazon then discovered it don’t work with Soft Start routers). In the end, the assessment was that the effort and cost wasn’t really worth the benefit for me.

Check out the thread about modifying the Dewalt for external speed control. Its essentially a free mod. The only cost is buying a $2 potentiometer and wires.

GWizard is nice but its more helpful for harder materials than for wood. Wood seems to be pretty forgiving and tolerates a wider range of cuts, feeds and speeds. There are probably some free online programs that will get you in the ballpark anyway.

There’s a bit of a page on the wiki: http://www.shapeoko.com/wiki/index.php/Materials#Testing_Cuts.2FMaterials

The Precise Bits folks advocate a technique which has worked well for me: http://www.precisebits.com/tutorials/calibrating_feeds_n_speeds.htm

One day when I have some time, I hope to clean up the feeds and speeds on that page, add columns for the machine types, make everything sortable and do an initial set of values for wood based on Janka hardness.

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Also, for G-Wizard, buying it for one year, will then afford one a perpetual license for a 1HP install, which is all that a hobbyist is likely to need.

G-wizard also goes on sale from time to time, making that one year subscription a little cheaper. The 1-year-good-forever-at-1hp deal isn’t actually all that well advertised over there.