Nope.? Not missing anything.

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Even with motors on the X and Lathe Z when the system is converted over to the mill making the ?axis now X and the X axis now a Y (from a CNC perspective) the motion of the vertical assembly (now Z axis) is very difficult to automate on the DB200 so it’s truly a 2 ? axis mill.

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The thing about automating and threading is the lathe part and because the motor is as underpowered as it is, any kind of cutting load causes motor speed change.? That pretty well disqualifies 1 PPR sensing for speed and therefore my ELS project.? But that project was started in 2005 when used encoders were $400 and stepper motor drivers were well over $100.?

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Now we have all the cheap stuff that could never be manufactured in North America or Europe being done in China at 1/10^th the cost.? A Pi4 with MESA 7i92 can handle say a $35 360 line encoder connected with cheap toothed pulleys and belt to the spindle and full LinuxCNC to drive the Z and X.? If you don’t want the MESA card and just Pi4 I/O it’s still possible to do that with Pi4 I/O pins but there are limitations.

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To quote Sam Sokolk from the LinuxCNC forum: “Any way..

Let’s say you have a 25khz base thread.

Encoders - You should be able to approach counting at 25khz if the quadrature signal is perfectly 50%.? (I might go 10% less) So - at 600 line encoder or 2400 count?? The absolute max counting rpm would be 625.”

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Drop that down to a 100 line encoder or 400 count then we’re up to 3750 RPM or if you can run the base thread at 50kHz then theoretically you can expect to handle at most 7500 RPM which now closer to the Unimat max speed.? In my case I was looking at using a 60 tooth sensor on my Gingery Lathe but this project was put on hold back in 2017 based on the photo and cad file dates.? With a 25kHz base thread the RPM range of this lathe would be easily handled.?

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But for the cost of the MESA product the encoder is counted in hardware so no longer matters.? And CNC is just a matter of the mechanicals;? mounting motors, encoders, power supplies and wiring.

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Or just use taps and dies.

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John