Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: lab auto man on March 23, 2017, 08:13:12 PM

Title: Homing the wrong direction
Post by: lab auto man on March 23, 2017, 08:13:12 PM

Hello,
I did some MDI cutting on my router and now the X axis is homing the wrong direction.   The limits and homing is still set to home negative but it goes positive when I ref all.  Could have I typed something in the MDI limit that caused this change?  I powered everything off and on and it still goes positive when I home the X axis.  Any ideas
Thanks,
Todd

Title: Re: Homing the wrong direction
Post by: MICHELDA on March 24, 2017, 11:46:54 PM

I had  a problem similar to your, and in when on window motor output and i remove step low active green tic......it is a suggestion

Title: Re: Homing the wrong direction
Post by: joeaverage on March 25, 2017, 12:48:22 AM

Hi,
it is certainly possible to just reverse the direction of the motor by checking/unchecking the active low setting of the direction
pin of that motor on the Config/Ports and Pins/Motor Outputs page. It will mean that the axis reverses direction, so if a program
calls for a cutting move to the right it will in fact go left. If you write your own Gcode you can overcome that but if you try using
code written by someone else or maybe generated by a wizard or a CAM program you could come unstuck.

The correct method is Config/Homing-Limits page. There you can reverse an axis and/or cause the axis to home in the opposite
direction. Experiment with it for a few minutes and you will find the right combination for your machine.

Craig

Title: Re: Homing the wrong direction
Post by: joeaverage on March 26, 2017, 02:36:19 AM

Hi,
just had another thought that might explain what you've described...could you have caused a negative scale factor?
Whether it would cause homing in the wrong direction I don't know but it could certainly screw you up!

Craig

Title: Re: Homing the wrong direction
Post by: MICHELDA on March 26, 2017, 07:39:53 AM

Ok. let me explain  my problem......when i click "go to zéro" the x and y axis move to the right direction and then the z axis go up. what i would like, it is the opposite.......z first go up and then x and y.......thks

Title: Re: Homing the wrong direction
Post by: ger21 on March 26, 2017, 10:37:57 AM

Enable Safe Z

Title: Re: Homing the wrong direction
Post by: lab auto man on March 26, 2017, 09:08:31 PM

Back working on X homing in the wrong direction.  I noticed that if I switch to machine coordinates my X is -4.123   That means the software thinks I am on the other side of my home/limit switch?  The question I have is even with it set to home X in the negative direction does the software think i am already past the home switch and moves positive looking for the home switch?  The other question is how can I type in or enter a positive value for my X machine coordinates and try homing ? 

Thanks
Todd ???

Title: Re: Homing the wrong direction
Post by: lab auto man on March 26, 2017, 09:48:04 PM

Never mind my mistake.  Somehow the home negative was set to home positive.  How it got switched ?
thanks
Todd

Title: Re: Homing the wrong direction
Post by: DonMarkey on April 03, 2017, 07:57:45 PM

Quote from: ger21 on March 26, 2017, 10:37:57 AM

Enable Safe Z

How is it related?

Title: Re: Homing the wrong direction
Post by: ger21 on April 05, 2017, 07:46:36 PM

It was a reply to the previous post