Maximum step rate?

Board: Laserboard

Firmware: Smoothie or GRBL-LPC

Question: I am currently building a new 2020 machine from scratch and am curious what the theoretical/practical maximum step rate for X/Y are using either of the firmwares?

Is there an upper limit to combined steps/second for all axis or per/axis?

Would like to know what I can expect given ideal circumstances so that I can better tune to reality.

My X-axis(200oz/in) is going to be very light to handle high speed raster. The Y-Axis will have a large (280oz/in) throwing the gantry around with ease.

I have some DM542T drivers and a 40 volt linear power supply so X and Y have lots of power.

I also have a 60W tube and new power supply which should be a lot better than the ~40W K40 one that died within a month.

Thanks!

Smoothie tops out at about 90K steps/sec while grbl-lpc does about 110k steps/sec. This should suffice for vector cutting moves unless you set your drivers Microstepping to really high values.

For raster scanning, the limitation would be the microcontroller’s ability to receive and process incoming gcode.

This is a linear axis speed test running on a C3D Laserboard I did last year. 80K steps second. This is a G0 move and not raster gcode.

1000mm travel movements
2000mm/sec velocity
20,000 mm/sec^2 acceleration

THK HSR15 Linear Rail 1200mm length mounted on OpenBuild 20x40 vslot extrusion
Nema17 Stepper 1.7amp 76oz-in
GT2 20 tooth 2mm pitch belt
Cohesion3D board running Smoothieware
DM542 Stepper Driver at 45volts
8 microstep

2 Likes

Very cool! Thanks for the details, that is exactly the kind of info I was hoping for.
Same drivers too!

I will be running 40 volts with beefy Nema 23 motors, should be plenty fast :slight_smile:

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.