Negative X readings and dropping Z axis
Have two probably trivial questions, however not so for me..
1)On my newly setup cnc my axes are moving fine, however for X axis my digital readout in Mach3 is showing negative values when my spindle is moving from left to right. meaning my 0 is at the most left edge of the table and instead of going to positive it goes into negative..
Ctrlr is Stb 5100, Motor Driver Tb6600. using laptop/usb.. Reversing in homing and limits does not help..
2) When ever my system gets into break mode whether bec of hitting the limit switch or emergency button or after a change of value of parameters in Mach3 when system flashes “Reset” the stepper motor at that time does not have the power and my heavy spindle drags the axis to the bottom. How can I somehow lock the z axis at these times so it does not slide down, becouse I have to re home it every single time after that.
Thanks!
Re: Negative X readings and dropping Z axis
1) Either the X or Y axis is setup backwards.
2) You need a brake on the motor.
Any time you hit a limit or Estop, the machine will lose position, and will always need to be re-homed, even if it had a brake.
5 Attachment(s)
Re: Negative X readings and dropping Z axis
On Question 1.. Not sure what you mean by backwards.. I attached my Mach3 setup which is preset from a manufacturers CD.. (USB/ laptop)
Cable from Driver Board to Controller is manufacturer prewired: plug x slot on one to x slot on the other, no wire by wire hookups. Really not sure, what’s going on here. The axis are moving in proper direction when jogged.
Thanks for help.
Re: Negative X readings and dropping Z axis
Is this a moving table, or moving gantry? Are you using the right arrow key to jog to the right, when it counts down?
Which way does the Y move with the up arrow, and with the down arrow?
Re: Negative X readings and dropping Z axis
Hi Gerry,
This is 1m x 1m machine with Gentry.
Without reversing, when I press LH arrow spindle moves RH and counts from 0 towards negative X values. I can fix movement with "reverse" X axis and it will move to correct side, however it will still go towards negative X when going to RHS.
Y axis works fine with resp to movement and count, away from me is Y+.
Z axis has limit switch at the highest position of the gentry/spindle. Spindle moves correctly Up/Down with PageUP/PageDOWN. From the top position going down, however, it goes into Z+ direction and my intention was to go into Z-.
I tried all different positions of my X and Y limit switches combined with appropriate homing direction changes for these positions and I could not get a normal coordinate system, so that X goes positive towards my RHS, Y goes + when going away from me and Z going Z- when going from top pos zero downwards.
Re: Negative X readings and dropping Z axis
Quote:
Without reversing, when I press LH arrow spindle moves RH and counts from 0 towards negative X values.
This is the motor moving the wrong direction. Checking Reverse will correct this.
Quote:
I can fix movement with "reverse" X axis and it will move to correct side, however it will still go towards negative X when going to RHS.
When you check Reverse, it should then move left with the LH arrow, and count down while moving left. The RH arrow should move to the right, and count up.
It sounds like you are saying it counts negative in both directions?
Quote:
Spindle moves correctly Up/Down with PageUP/PageDOWN. From the top position going down, however, it goes into Z+ direction and my intention was to go into Z-.
Are you saying the Page Down moves the Z axis down, but it's counting up??
Have you changed any of the jogging hotkeys?
By default, everything should work as you'd expect, with the only necessary changes being to possibly reverse the motor direction.
If you haven't changed any hotkeys, you might want to uninstall, and reinstall from scratch, as something seems very wrong.
Re: Negative X readings and dropping Z axis
I am moving the gentry only with the arrow keys on my keyboard have not used or modified anything else no hotkeys, I have not made a run on it yet..
Yes no matter how I move gentry in X it counts negative from LH to RH.. I home my Zero at leftmost and when I move towards RHS in counts -1, -2, -3, ...
Likewise for Z I am at the top at Z=0 and I move it down with PageDown and it Counts: 1, 2, 3...
Reverse is "reversing" where getry moves when I press arrow keys on my keyboard but counting always stays the same.
Re: Negative X readings and dropping Z axis
Jog to the middle of the table with the X axis, and press the Zero X axis button. Now jog to the right. It should count up in positive numbers.
Do the same for the Z axis.
Re: Negative X readings and dropping Z axis
I tried and it did not work...
However I just found a solution I was not expecting. I went in and changed X and Z status in Ports/Pins, Motor Outputs from Low Active to Hi Active (unchecked Low Active which was on for these two axes..
Solved the problem completely..
Thank you for your help regardless.
Re: Negative X readings and dropping Z axis
My guess is that your STB 5100 does not properly support the "Reverse" option in Mach3.
Technically, checking "Reverse" should be exactly the same as changing the Active Low setting.
I hate chinese controllers. You spend so much time looking for the problem, when the chinese controller is the problem all along.
Re: Negative X readings and dropping Z axis
I thought the same at first.. Cannot say I didn't know what I signed up for.. Most "confident" people chose to deal with issues and frustration to save the greens.. faith of our generation..
