Messages

61

General Mach Discussion / Re: Unusual stepper issue on lathe

« on: September 03, 2017, 07:11:17 PM »

Many thanks for your input Craig
Many years ago, when I set the lathe up, I had problems with electrical noise. I was using a USB Smoothstepper and I think from memory (always a dangerous thing), that the option to alter the noise filtering of inputs was not in the driver at that stage. Time passed and I moved to an Ethernet Smoothstepper which had the "noise filtering of inputs" option in the driver, and in conjunction with the anti-interference measures that I had already put in place for the Usb Smoothstepper (shielded cat 5 cables for motor and VFD connections etc), the lathe worked well for years.
This was a new problem that only reared its head at the last moment when I started boring the pulleys for the servo motors.
Although I may have sounded rational in my posts, a little voice inside my head was saying " you know that it is malignancy on the part of the equipment that is causing this."

62

General Mach Discussion / Re: Unusual stepper issue on lathe

« on: September 02, 2017, 07:54:03 AM »

I initially thought along the same lines Tweakie, thanks for the suggestion  anyway. As I said it doesn't really matter now, but I'd like to know what caused it, if only for academic reasons. The strangest thing about the problem was that, although I didn't mention it in my last post, I fully reinstalled a fresh copy of M3 then used an XML file from a backup that I knew was working with the VFD in question. I suspected it was a wiring issue, but I wasn't prepared to fault find it any further.
Another strange thing was that it never reared it's ugly head when running a cycle, it only failed after a cycle had finished.
My theory, for what it's worth, is that the disable line on the Gecko was close to disabling the drive, and did so occasionally, but only kicked in after use, since, during a cycle the load on the power supply was sufficient to keep the voltage below the TTL threshold. We will however, never know.
Dave

63

General Mach Discussion / Re: Unusual stepper issue on lathe

« on: September 02, 2017, 02:08:12 AM »

I eventually worked out the cause of my problem, rather I should say, the solution to the symptom manifesting itself as the Z axis not moving when the spindle was running. The disable signal to the G203V stepper driver was going high, only when the spindle was on. The solution was to temporary remove the disable wire from the G203V. This isn't really an answer, but since I am in the process of installing servo motors and drives to replace the steppers and the spindle motor, it doesn't really matter any more. I have bored my pulleys, so I can fit my servos.

64

General Mach Discussion / Re: Unusual stepper issue on lathe

« on: August 30, 2017, 11:28:36 PM »

A bit more info, since I've no replies yet (hint) The DRO for Z changes to reflect the commanded position, but when the spindle is moving the axis doesn't move. An example - Without the spindle running from the MDI with Z at 50 - I type the command G0Z150 this moves the Z axis to 150mm as expected. I type the command G0Z50 this moves the Z axis back to 50mm as expected. With the spindle running from the MDI with Z at 50 - I type the command G0Z150 this doesn't move the Z axis at all the DRO however updates as though the axis were moving. I type the command G0Z50 doesn't move the Z axis at all the DRO however updates as though the axis were moving.

65

General Mach Discussion / Re: Unusual stepper issue on lathe

« on: August 30, 2017, 10:08:13 PM »

Ironically the reason for boring the pulley, is to replace the VFD with a servo and driver. Perhaps the issue is that the VFD has got its knickers in a twist because it doesn't want to be retired? It has worked well for 10 years.

66

General Mach Discussion / Unusual stepper issue on lathe

« on: August 30, 2017, 10:04:22 PM »

A couple of days ago, I played with my VFD settings, I don't remember what I did, but I didn't think I had altered anything that would upset Mach3 on the lathe.
Today, I decided to bore a pulley, but when I started the spindle, I had no Z axis movement. I stopped the spindle and both axis are moving as per usual, but running a Gcode file generated with the boring wizard, or even starting the spindle with the spindle on button results in no motion from the Z axis. I have tested the X axis, it works as expected.
I am perplexed.
I am expecting it to be something I've done when playing with the spindle, but maybe not.
Thanks for your help
Dave

67

General Mach Discussion / Re: Using servo for spindle on lathe

« on: March 15, 2016, 08:03:34 PM »

Yes
I didn't have this issue with the CSMIO
Here are the working Ess settings for posterity.

68

General Mach Discussion / Re: Using servo for spindle on lathe

« on: March 15, 2016, 07:58:04 PM »

Well I did think about putting the scope on the output, but I thought I'd ask first.I'm glad I did.

Seems funny going to bed at 11:00am.

Sleep well

Dave

69

General Mach Discussion / Re: Using servo for spindle on lathe

« on: March 15, 2016, 07:55:20 PM »

Well I've experimented and cannot get 2500rpm with a pulse width above 1. Unless you can have decimal points in pulses, Ie: 1.5, but I think I'll leave that for another day. I can get on with my fitting now
Thanks again
Dave

70

General Mach Discussion / Re: Using servo for spindle on lathe

« on: March 15, 2016, 07:46:22 PM »

I don't know how to thank you enough Hood. I knew it would be a simple solution, but it helps incredibly to talk with someone who knows all about these things.
The problem was caused by the spindle pulse width, I hadn't changed it before, because I though that what was Ok as an axis, should also be Ok for the spindle.
I'll just have a fiddle and see what is the maximum pulse width I can have. At the moment it is working with a pulse width of 1.
Should I use whatever pulse width it works with, or should I be conservative and set it one unit below whatever works?