Messages

41

General Mach Discussion / Re: Indexing Problem with R.3.042.032

« on: November 16, 2009, 07:46:19 AM »

Update on indexing problem.

In the thread "Problems Threading on the Lathe", Art has explained that SPINDLE has to be on in version R.3.042.032 for indexing to work.

This explains why I was always getting zero RPM when spindle was under manual control.

The negative RPM problem remains. Following test carried out:

Start Mach
Disconnect spindle motor electrically
Select SPINDLE button on screen (or run M3)
Rotate spindle slowly by hand
As the index slot passes the opto switch the INDEX LED flashes and the True RPM changes from 0 to approx minus 50 RPM
Stop rotating spindle
True speed DRO remains at minus 50 RPM
Toggle SPINDLE button on and off, with spindle stationary, RPM alternates between 0 and minus 50
This condition remains until MACH is restarted.

The same test carried out on version R3.042.020
As the index slot passes the opto switch the INDEX LED flashes and the true RPM changes from 0 to approx plus 70 RPM
Stop rotating spindle
True speed DRO returns to zero RPM

Under normal running conditions R3.042.020 is effectively displaying the correct RPM over the entire speed range.

Version R3.042.032 displays zero RPM until the first pulse has been detected from the indexer, then dispalys a negative value whenever the SPINDLE button is on. This negative value does change as spindle rotation speed changes but is not proportionate to the true speed.

Any ideas anyone ??

Thanks

Peter

42

General Mach Discussion / Re: Indexing Problem with R.3.042.032

« on: November 13, 2009, 07:44:27 PM »

Rich

It would appear to probably be the same problem, just showing itself slightly differently. But there again, .030 was working on your system but I also had problems with that version.

Just for the record, I have so far tried manually uninstalling the driver, completely unistalling mach from the computer, then reinstalling with the standard mach3 turn profile configured with just enough to get the motors turning and the index enabled. The problem is the same as with my normal turn profile.

BTW, I didn't previously mention but my system is connected via PP.

Peter

43

General Mach Discussion / Re: Indexing Problem with R.3.042.032

« on: November 13, 2009, 08:00:46 AM »

Rich, thanks for your reply. I accept what you say about the tacho and the RPM does indeed fluctuate by small amounts, around 1 RPM in the realtime speed box. As I understand it, you are saying that the realtime speed is conditioned into the application end RPM for threading, which makes sense.

I guess something in my setup is interfering with the process of conditioning the realtime speed in the latest software releases.

Thanks for the explanation.

44

General Mach Discussion / Re: Indexing Problem with R.3.042.032

« on: November 12, 2009, 06:19:45 PM »

Hi

Can anyone advise on the relationship between Rotation Speed Realtime and Application End RPM in Turn Diagnostics. The Realtime RPM is shown as a stable and true representation of the actual spindle speed, which suggests to me that Mach is receiving a good signal from the indexer.

The Application End RPM is displaying a negative value and it is this figure which is showing up in the True Speed DRO.

Under R.3.042.020 both realtime and application end RPM are the same.

45

General Mach Discussion / Re: Indexing Problem with R.3.042.032

« on: November 10, 2009, 08:00:43 AM »

Hi Rich

Thanks for your reply.

I tried changing the index debounce. I usually have mine set at 2, but I tried it up to 200 at various stages without any change.

I loaded version .030 and this time I got the same RPM in both auto and manual spindle control. That is at 500 RPM it is indicating minus 218 RPM in both auto and manual.

The 500 is just an arbitary figure. For example at a commanded speed of 200 the indication is minus 88 and at 1000 the indication is minus 433. At the commanded speed, the actual speed measured with a tacho is within 1 or 2 RPM at mid range (500) and within 5 RPM at 1000.

When I first upgraded to version .031 I tried to run a spindle calibration but because it was showing minus, it wasn't even registering on the graph, so I aborted.

I am now back with version .020 and it is normal again.

Peter

46

General Mach Discussion / Indexing Problem with R.3.042.032

« on: November 10, 2009, 06:42:31 AM »

Hi

Is anyone else having problems with indexing in the latest release.

I have been running R.3.042.020 for some months, using a single slot index disc with a good stable RPM indication.
I upgraded to R.3.042.031. and experienced the following problems:

Under automatic spindle control (Digispeed controller and VFD) RPM is showing as a negative eg. -218 RPM at a true speed of 500 RPM. Under manual spindle control (potentiometer and VFD) RPM indication is 0 RPM at all times.

I changed back to R.3.042.020 and normal speed indication was restored in both auto and manual spindle control. I then upgraded to R.3.042.032 and had the same problems as above.

If I run the Turn Diagnostics plugin, I am getting a Rotation Speed Realtime of 501 RPM in both cases and an Application End RPM of minus 218 RPM under auto spindle control or 0 RPM under manual spindle control.

I have now reverted again to R.3.042.020 and speed indication is normal again in both auto and manual.

Just wondering if anyone else is having problems.

Peter

47

General Mach Discussion / Re: Problems threading on the lathe

« on: November 04, 2009, 09:09:52 AM »

Hi Rich

I think many people are going to benefit from all the testing you have done together with your excellent write up. Many thanks for all your hard work.

Peter

48

General Mach Discussion / Re: $5000 retrofit

« on: September 28, 2009, 07:13:14 PM »

Hood

I have a Bridgeport that uses AMC drives, although not currently under mach 3. I am based in UK but I have always dealt directly with their office in US. I had a couple of drives fail due to a problem on one of the axis servos and I got good service from AMC on both sales and repairs of the faulty drives.

Peter

49

General Mach Discussion / Re: whats happening with threading

« on: December 04, 2008, 03:23:06 PM »

I am now seeing repeatable screwcutting without errors in both G32 and G76.

50

General Mach Discussion / Re: whats happening with threading

« on: December 04, 2008, 01:59:07 PM »

I have just cut 6 successful threads, 3 in G32 and 3 in G76. I solved the momentary blip in spindle speed feedback by switching off enhanced pulsing in general configuration.

I still have the same faults in auto speed, but that is a seperate problem. I will try some more tonight to see if the faults re-occur.