Hello Guest it is October 22, 2019, 07:50:30 AM

Author Topic: G540 Steps Per  (Read 3220 times)

0 Members and 1 Guest are viewing this topic.

Offline kolias

*
  •  1,011 1,011
    • View Profile
G540 Steps Per
« on: January 28, 2017, 11:31:24 AM »
I got a new G540 and using the .XML from Gecko (540BVFD) the steps per setting is 20000 which makes my motor running very rough. Using the Mach3 “Set Steps per unit” on the Settings tab it gives me a steps per of 4002 which is pretty close to what I get with my calculations assuming a 1/8 microstepping. (my cals: 200 x 8 x 2.54 = 4064 with 10mm Lead ball screws)

What microsteps the G540 is using and can I change them?
Nicolas
Re: G540 Steps Per
« Reply #1 on: January 29, 2017, 12:02:59 AM »
Hi,
what are you using as native units? Found on the Config/Select Native Units menu, set them once and then leave them alone. You can
use the alternate units for your Gcode jobs but DONT use this setting to achieve it, use codes G20/G21 instead.

If in mm which is a natural choice if using metric ballscrews the steps per unit would be:
200 full steps/rev times 8 microsteps per fullstep equals an axis movement of 10mm
ie 160 steps/mm.

If in inches:
200 full steps/rev times 8 microsteps per full step equals 0.3937 inch per rev
ie 4064.008 steps/inch.

Craig
My wife left with my best friend...
     and I miss him!
Re: G540 Steps Per
« Reply #2 on: January 29, 2017, 01:21:47 AM »
I got a new G540 and using the .XML from Gecko (540BVFD) the steps per setting is 20000 which makes my motor running very rough. Using the Mach3 “Set Steps per unit” on the Settings tab it gives me a steps per of 4002 which is pretty close to what I get with my calculations assuming a 1/8 microstepping. (my cals: 200 x 8 x 2.54 = 4064 with 10mm Lead ball screws)

What microsteps the G540 is using and can I change them?


The G540 is a 10uStep drive. You cannot change that. If you have a 100 pitch leadscrew then the steps/unit (mm as that's what your lead screw is) the calculations are;

200steps/rev * 10ustep  = 2000 steps for 1 rev of the motor.

since 1 rev of the motor moves the axis 10mm then we get 2000/10 = 200 steps per mm

If you want to set your native units to imperial, then multiply the 200  * 25.4 = 5080 steps/inch.

Cheers,

Peter
----------------------------------------------------
Homann Designs
http://www.homanndesigns.com
email: peter at homanndesigns.com

Offline kolias

*
  •  1,011 1,011
    • View Profile
Re: G540 Steps Per
« Reply #3 on: January 29, 2017, 02:39:01 AM »
Thanks guys for the answers and BTW I use inches despite that my ballscrews are metric.

I wonder why Gecko uses 20000 since not all users will have a 10mm pitch ballscrews and although I do have 10mm ballscrews I have to use 4064 as Steps per
Nicolas
Re: G540 Steps Per
« Reply #4 on: January 29, 2017, 05:55:02 AM »
4064 is incorrect.

If you have a 10mm pitch leadscrew then with a G5640 the steps/inch is 5080.
The G540 is a 10ustep drive. It is NOT an 8ustep drive.

Peter
----------------------------------------------------
Homann Designs
http://www.homanndesigns.com
email: peter at homanndesigns.com

Offline kolias

*
  •  1,011 1,011
    • View Profile
Re: G540 Steps Per
« Reply #5 on: January 29, 2017, 06:27:18 AM »
My mistake Peter, 5080 is correct

Thanks
Nicolas

Offline ger21

*
  • *
  •  6,288 6,288
    • View Profile
    • The CNC Woodworker
Re: G540 Steps Per
« Reply #6 on: January 29, 2017, 10:48:24 AM »
Quote
I wonder why Gecko uses 20000 since not all users will have a 10mm pitch ballscrews

When there are an infinite number of possibilities, what are they supposed to use?
The .xml 's purpose is mainly to configure the inputs and outputs correctly.
There are numerous settings in an .xml file that are very different from machine to machine, even when the machines are the same.
Gerry

2010 Screenset
http://www.thecncwoodworker.com/2010.html

JointCAM Dovetail and Box Joint software
http://www.g-forcecnc.com/jointcam.html

Offline kolias

*
  •  1,011 1,011
    • View Profile
Re: G540 Steps Per
« Reply #7 on: January 29, 2017, 04:08:40 PM »
I understand Gerry, thanks however perhaps Gecko should have put a note somewhere stating the 20000 may not be applicable to all users. I spent more than a day trying to configure my 4 motors to run smooth because I thought if Gecko says to use 20000 they must be right

Nicolas
Re: G540 Steps Per
« Reply #8 on: January 30, 2017, 04:18:07 PM »
I understand Gerry, thanks however perhaps Gecko should have put a note somewhere stating the 20000 may not be applicable to all users. I spent more than a day trying to configure my 4 motors to run smooth because I thought if Gecko says to use 20000 they must be right



I'm a bit surprised that you are apportioning blame to Gecko.

The steps per unit value is dependent on the following;
  • Micro steps of the stepper drive,
  • Steps per revolution of the motor
  • Pitch of the lead screw
  • Mechanical gearing in the drive train for an axis.


Out of the five variables above, Gecko is responsible for one of them.

If you had read the manual http://www.machsupport.com/wp-content/uploads/2013/02/Mach3Mill_1.84.pdf specifically section 5.5 Tuning Motors you would understand that Gecko would never suggest a value for your machine. It would be clear that the XML profile provided by Gecko sets up the input and output pins for their G540 drive.
They cannot know the steps/per value, or the velocity and acceleration values for your machine or any other machine.

Every Mach3 profile has to have a value in the steps per field. The ones in the profile from Gecko are most probably the values they use for the machine that they created the profile.

As a suggestion, read the manual cover to cover. You may not understand it all but enough will sink in so that it should jog your memory when you have questions.

Cheers,

Peter





« Last Edit: January 30, 2017, 04:20:18 PM by Peter Homann »
----------------------------------------------------
Homann Designs
http://www.homanndesigns.com
email: peter at homanndesigns.com

Offline kolias

*
  •  1,011 1,011
    • View Profile
Re: G540 Steps Per
« Reply #9 on: January 30, 2017, 07:49:22 PM »
....... It would be clear that the XML profile provided by Gecko sets up the input and output pins for their G540 drive.
They cannot know the steps/per value, or the velocity and acceleration values for your machine or any other machine.
Cheers,
Peter

I understand what you are saying Peter and for the fairness of all I still say that Gecko should have put a note somewhere in their Manual to say that in their XML the “Steps per” is only just a number and the user should establish their own value.

Let’s say I’m a guy who uses his mill for x number of years and one day I decide to use the G540 and since they provide an XML I say well Gecko is a big name might as well use their XML. I see the 20000 in their XML and I say well this number does not make any sense but since it’s provided by Gecko they must know something I don’t know or this number is something special for the G540. This scenario can happen to anyone

Another mistake on the same XML under Ports & Pins / Motor Outputs, Spindle line, the Step Port is 0. That should be 1 otherwise no PWM signal is generated (BTW I found this from another forum and it works for me)

I value the Gecko products and your knowledge Peter but that’s the way I see it and this post is not intended to blame anyone rather to state my experience and perhaps help someone.


Nicolas