My closed-loop stepper, 500ipm rapid, Centroid Acorn converted MR1 is ready for debut

Hey @Arcnsparks; got my closed loop steppers about to be delivered today. Did you mess with any of the settings? I’m sort of amping myself up and trying to have all this figured out before I start on it tonight. how did you tie the alarm circuit to the controllers? daisy chain them to the e-stop?

10 amp 48V power supply
2x 2Nm closed loop steppers
2x 4nm closed loop steppers
4x 10mm to 6.35 shaft couplings
4x power/ encoder extension cords
kit of aircraft connectors 4 and 8 pin

anything else I haven’t foreseen?

Yeah, looks good!

I didn’t need to do any tuning or any software driver modifications. I set the steps to 4000 as recommended by StepperOnline and then configured the centroid software as needed for movement commands. I set the amp output on the driver to the appropriate amp range of the motor. You might be aware, but this can go higher on the CL steppers since the driver only increases the amp output as needed based on the encoder input when in a move. No more hot steppers while sitting still in a hold state!

The alarm outputs were N/O so the were tied together in parallel and connected to a separate “driveOK” input on the Acorn. The Acorn then handles the eStop functionality automatically based on this status input.

I did notice that the Langmuir steppers were a little on the fancy side, having a lip seal installed on the output shaft. I couldn’t tell if the CL steppers from StepperOnline had any such provision but figured I’ll simply replace them if they fail or come up with a solution if it shows to be a problem.

What did the conversion to acorn and closed loop cost

Bringing this one back from the dead. With Cut Control development essentially stalled, it would be great to get wiring diagrams from @MrmachineTX and @Arcnsparks. I am contemplating a controller upgrade.

I am very familiar with 3d printers and get the basics of how it all works, but CNC is a little less forgiving (in my experience). @AlexW mentioned 5v for the probe and tool setter are an issue, I am curious how it was handle with other controllers.

I’ve been slowly getting stuff together for my Mesa 7I96s controller swap. Most controllers have a pull-up/ resistor in the Input for the probes and once they make contact pull the input low. It is similar to the probe but just constant 5v supply for the LED.

I just bought an Acorn and will start piecing things together Alex has enough generic info I can use and MrMachineTX does have some documentation out in Google.

I plan on documenting the process on GitHub. I want to make connectors/adapters for the existing cables so I can go back if something doesn’t work quite right.

I believe the board connectors are JST-VH. They look very similar to connectors used by Duet3D on their printer control boards. I have wire-to-wire connectors coming to test as a pigtail to the Acorn.

I published everything about my conversion to LinuxCNC here, including wiring tables:

The same information is useful for any conversion and I think it has been used by others doing their conversions.

1 Like