Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: inivator on June 10, 2008, 02:35:07 PM

Title: Direction change makes the stepper motor run ruff.
Post by: inivator on June 10, 2008, 02:35:07 PM

I am using the Probotix stepper motor controllers, and after tuning the axis motor, it runs smooth in one direction, but when I change direction, the motor runs ruff or stalls.  What am I doing wrong.

Need help please

Inivator

Title: Re: Direction change makes the stepper motor run ruff.
Post by: da21 on June 10, 2008, 02:55:10 PM

as a check disconnect the steppers / servos and turn the ballscrews by hand and see if you notice any binding or they being stiff more  in one direction etc , on the face it sounds as if you have some binding on slides or screws etc  ,or try reducing the tuning a small amount from what would be optimum .


Dave

Title: Re: Direction change makes the stepper motor run ruff.
Post by: Chaoticone on June 10, 2008, 03:10:30 PM

Also, might want to check your backlash settings.

Brett

Title: Re: Direction change makes the stepper motor run ruff.
Post by: M250cnc on June 10, 2008, 04:37:17 PM

Inivator

How are you changing direction ?

If you go from one direction straight to the other using fast jog you will get a screaming sound from the motors and you will loose position

You must let the machine come to a rest before changing.

If you are changing direction in a gcode program you may have the motor acceleration too high again you will loose position.

The bigger/heavier the table the slower the acceleration must be. Time spent here getting it right is time well spent.

HTH
Phil_H