Messages

11

General Mach Discussion / Re: Erratic Pendant operation

« on: November 08, 2009, 04:34:45 AM »

Yes, it is an MPG.  Not sure whether I did the calibration - will take a look at it in the morning.

12

General Mach Discussion / Tool holders - Tool Numbers - recommendations?

« on: November 08, 2009, 04:28:36 AM »

I have a CNC mill that uses NMTB-30 holders.  I have plenty of holders, so plan to leave cutters in place in the holders.  What I am wondering is whether there are any conventions, or just personal preferences that you may want to pass on, for a numbering system for cutters.  Or should I just number them randomly starting from #1?

Thanks,
Scott Kelley

13

General Mach Discussion / Erratic Pendant operation

« on: November 08, 2009, 02:31:58 AM »

Everything is set up and working well, except the pendant.

When I move any axis with the pendant, the movement is very erratic.  It accelerates and decelerates very fast (not in the controlled manner that it does in other instances), and it moves in "jumps" - for instance, if the increment is set to .001" and I smoothly rotate the wheel 2 turns (.200"), the axis will move that distance in multiple rapid jumps rather than in one smooth acceleration / deceleration movement.

On the other hand, using the on-screen jog controls, the axis movement is well controlled - all axis' accelerate and decelerate in a well controlled manner.

14

General Mach Discussion / Re: Trouble getting spindle speed to work

« on: July 13, 2009, 04:11:23 PM »

I would like to narrow this down to either an board issue, or a Mach issue. 

Is there a detailed specification somewhere of the outputs from Mach that will tell me what pin carries the PWM signal, and what the expected charicteristics of that signal are?

15

General Mach Discussion / Re: Trouble getting spindle speed to work

« on: July 13, 2009, 04:07:55 PM »

That didn't make any difference.

16

General Mach Discussion / Trouble getting spindle speed to work

« on: July 12, 2009, 06:58:33 AM »

I've been through all of the documentation that I can find, and cannot fully sort out the spindle speed issue. 

Right now I'm getting very strange results - sometimes get 16.66 Hz operation and sometimes less.  The highest voltage I've measured on the PWM output from my CNC4PC C11 breakout board is 2.7 volts (which corresponds to the 16.7 Hz). 

I THINK I have the pulley settings correct (Pulley 1 is set up for 420 - 4200 RPM, and I can input "S" codes within that range and not receive an error message.  However the speed only changes at the very low end of that range, and it does so in the opposite direction expected (for instance, speed will be at the minimum of 10 Hz. if I set the spindle speed for 3000 RPM, but will speed up to 16 Hz. if I set it for something like 500 RPM).

Some of the references in the manual are to (I presume) an older version of Mach, and are difficult to fully understand.  Is there a complete description of the setup for the spindle speed control somewhere?  Does anyone recognize these symptoms?

Thx
Scott Kelley

17

General Mach Discussion / Re: Trouble getting MPG to work

« on: July 11, 2009, 02:06:18 AM »

Hood - no, it doesn't work with Jog mode set to MPG.

I have learned more.  The problem seems to be that I am getting a signal from the MPG encoder pins only when Reset is ACTIVE in Mach.  When Reset is active (button flashing on Mach screen) I do get indicators on the status display in the Diagonostics screen as I rotate the MPG wheel.  So while it is in Reset mode, the encoder pins are working. 

When I press the Mach Reset button to take it OUT of Reset mode (the Reset button is no longer flashing, and all controls are now operable) the signal from the encoder pins no longer indicates on the status display in the Diagonostics screen.  At this time, the actual signals that I measure on the port are at a very low level - the high level is about .2 volts, and low level is about .o5 volts, (versus about .15 volts low and 4.70 volts high when Reset is active). 

So when reset is in the Run mode, either the MPG is not outputting anything, or the port pins are being pulled low by the computer.  It seems to me more like the latter, because there is some indication that the encoder is trying to drive those pins (Port 2, pins 3 and 4).

Any thoughts?

18

General Mach Discussion / Trouble getting MPG to work

« on: July 09, 2009, 05:14:30 AM »

I have a CNC4PC MPG2 pendant and C22 interface card installed.

In diagnostics mode, when pressing the enable switch and rotating the axis and resolution switches, I can see various combinations of the 7 "LEDs" illuminate to indicate the inputs from the X, Y, Z, and 4 axis', and the X1, X10, and X100 resolution switches.

I do not get any movement (Jog mode set to MPG and Jog turned ON) when rotating the wheel.

I do not see any LEDs illuminated that change with the rotation of the MPG wheel.  (I would think that 2 of the port 2 LEDs should be illuminating alternately as the wheel is turned... true?)

Jog does work with keyboard or on screen "button jog" inputs.

Any thoughts?  Ideas for further diagnosis?

Thx,
Scott Kelley

19

Mach Screens / What do I need for touch screen interface?

« on: July 30, 2008, 04:22:39 PM »

I am putting together a system to run a milling machine.  I like the idea of touch-screen control, in that it would seem to make the whole thing easier (less mechanical controls to implement).  Couple questions:

Do I need to look for anything specific in the touch-screen itself, or will any brand / model work?

Is there a suitable touchscreen "driver" available for 3, possibly 4 axis mill, or would I need to create something?  (I am trying to make this as simple as possible)

Anything specific that I should know before committing to using a touch screen.

Thx
Scott Kelley

20

General Mach Discussion / Re: Hardware suggestions?

« on: July 27, 2008, 04:26:36 PM »

As noted, they are 140 volt brush type servo motors.  The encoders are a BEI model that I think I have enough info about to be able to use them.

For motor drives, I have seen that Rutex and Viper are both available in a 200 volt model.  It was suggested to me that there have been some problems with some of the Rutex drives - any thoughts there?

The area where I am pretty well baffled is that of the interface between the PC and the motor drives, limit switches, etc.