Which mode is best for new setups?

The important thing is that you set your minimum step timings correctly in your configuration and you shouldn't have any problems.
I would use:
Step Time=2000
Step Space=2000
Dir Hold=50000
Dir Setup=2000
These are double the specified minimums in the Clearpath manuals. If those timings are too restrictive for your machines performance (can't go fast enough) you could try 1500 and 30000, but I don't think I'd fully trust a whole lot less.

I've never used a Clearpath motor, but I am using several older Teknics servos. I don't think they were available yet when I converted a stepper machine to servos.

I believe Thadwald ran into trouble because he didn't bother changing the settings from his old config after upgrading.

Clearpath User Manual

Relevant page:



The step pulse timing is specified separately for each axis in your .ini file like so:
I think DIRSETUP could be 25ns instead of 1200

As for getting the distance per step right, you simply enter pulses per unit (in. or mm) as the SCALE parameter in the .ini file:
I use inches, the motor is directly coupled to a 0.5" pitch lead screw, and the Clearpath motor is set to 3200 steps per revolution
Negative SCALE reverses the axis direction
6400 pulses move the axis 1 inch. Backwards.

Todd Zuercher wrote: I believe Thadwald ran into trouble because he didn't bother changing the settings from his old config after upgrading.

Quite right. I had each timing value set to 200 ns...

what scale are these numbers in?

Step Time=2000
Step Space=2000
Dir Hold=50000
Dir Setup=2000

For instance Thad said 25ns instead of 1200, so is 2500 = 25ns?
And when he had 200ns was his setting 20000 instead of 20ns 2000?

Just trying to get a clear picture.

LinuxCNC's step timing numbers are all in ns so 2000 is 2000 ns or 2 us

There is no disadvantage is setting the direction setup and hold times quite large
( 10000 ns will work with almost any drive and has no real impact on performance )

OK thanks Peter. So Thad's issue was that he had these values way too small and this was causing his missed steps. I will try the suggested values:

Step Time=2000
Step Space=2000
Dir Hold=50000
Dir Setup=2000

Do you think this is a good starting point for my Clearpath servo motor or should I go higher?

The numbers are in nanoseconds.

Making pulses too short will cause the signals to fall outside the range of the Clearpath specs and it recognizes it as noise (my problem). Making them too long will impose a speed limit on your motor because the longer the pulses, the fewer of them you can send in a certain amount of time. With 4000ns step + space and 800 pulses per revolution on your motor, this speed limit is 18,750rpm.

The numbers will work fine.

Perfect thanks. Yeah my motor max RPM is only 1130 so I'm totally fine.

hatch789 wrote: It would be neat to hear this with CNC machines. Though in my opinion a terrible waste of time and raw productive power.

There is a sample file in the LinuxCNC installation called "daisy.ngc". All it actually does is play the tune "Daisy ", Though it requires a 4th axis to be present to run.

thadwald wrote: The numbers are in nanoseconds.
With 4000ns step + space and 800 pulses per revolution on your motor, this speed limit is 18,750rpm.

The numbers will work fine.

Hmm, thats about 352 metres a minute on my machine. Now I just have to find a motor that will turn that fast! I don't think Clearpath have one.