Video: trochoidal slotting in aluminum on shapeoko 3

Hi everybody,

I thought you might enjoy my attempt at trochoidal slotting on the Shapeoko 3; this is 6061-T6 aluminum, 0.250 thick, 0.250 2-flute carbide stub end mill, full axial engagement, 0.01 radial engagement, maximum possible feed rate (200 ipm but acceleration-limited, not sure what it really is), 16-18krpm, so 0.00625 nominal feed per tooth, actual chip load 0.0025. i should probably raise the radial engagement since the tool speed is lower than requested. anyway, it’s nice not to have to police the chips continuously, and to spread the tool wear over the full depth of the cut. rough cut is fairly … rough, so i do a number of slower finishing passes, 20 thou total (more than necessary). anybody else doing this sort of thing with the Shapeoko 3 (or 4 or pro)?



I’m trying to work out some similar parameters on the Nomad 3. Except with a 1mm diameter two flute.

So far I’ve managed about 1.5mm doc with a 0.3mm radial engagement in copper… feels like you’re blowing me out of the water :melting_face:

Videos like that make me want just a bit more power.

Here’s a good thread.

If you search for aluminum on the forum, you’ll find there are plenty of examples.
What CAM program are you using? Lots on adaptive toolpaths as well.


thanks for the link! lots of interesting stuff there.

re: my project, what I’m doing is trying to maximize the linear rate of through-slotting in 0.250 plate, while minimizing the risk of chip welding, and maximizing tool life, thus the full DOC. finish is unimportant.

I’m using fusion. I think I should be able to take more (double?) radial DOC because the machine can’t deliver the full feed rate. i suspect that the stepper drivers should be able to detect stalls, and use that to set an alarm, but I don’t see anything like that in the firmware.

Do you have the stock controller? If so, the drivers can not detect stalls.


huh. that’s a bummer. is there a different common grbl controller that does?