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lathe threading problem - ghost trigger
« on: February 27, 2010, 10:15:02 AM »
Sorry if this has been covered before. I spent a while looking for related issues without success. You can probably skip over all but the last two paragraphs. I don't think the problem has anything to do with my wiring.

I started with the CNC4PC index pulse card, and setup the index with a slotted disc pretty much as described. I mapped it to an input port, enabled the spindle output (not sure why this is required), and entered an m3 command. The spindle RPM reads correctly.

The code produced by the threading wizard, however, appears to start each pass without waiting for a pulse. I thought I might have a noise problem, checked the signal with a scope, but it looks fine. I then switched to using a hall effect sensor I had laying around, and while the RPMs still read correctly, the gcode from the thread wizard still starts seemingly without waiting for a pulse.

OK, I mapped the index input to the estop input to make sure it stayed off, disabled the spindle output, turned off the spindle: true RPM reads zero. I run the code output by the wizard in diag mode, and the index led remains off the entire time. I see the wait for trigger led come on, then go off and a thread pass is started. Where is it getting the trigger?

I started with the latest version, but removed it and installed version 033 based on recommendations in numerous threads.

Thanks - Jeff

Offline Hood

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Re: lathe threading problem - ghost trigger
« Reply #1 on: February 27, 2010, 10:40:59 AM »
Can you attach your xml please.
Hood
Re: lathe threading problem - ghost trigger
« Reply #2 on: February 27, 2010, 10:58:45 AM »
Try ading a delay to the spindle

Config, ports Pins, Spindle Setup

You may need to adjust the delay to suit, try 3 seconds to begin with.

Phil
The Good Thing About Mach3, Is It's very Configurable

The Bad Thing About Mach3, Is It's Too Configurable
Re: lathe threading problem - ghost trigger
« Reply #3 on: February 27, 2010, 11:43:32 AM »
I attached my xml file. It should be very close to the default machturn file.

Setting spin up and down delay didn't have an effect.

Thanks - Jeff

Offline RICH

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Re: lathe threading problem - ghost trigger
« Reply #4 on: February 27, 2010, 12:03:03 PM »
G32 ( threading ) is just like a G1 ( linear move ) except the g32 requires Mach to recieve a timing index pules to activate the move.
RICH
How many sensors does your Hall effect sensor have? Mine has two and you only want one of them sensing the magnet.

I take a quick look at your xml.....

Offline RICH

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Re: lathe threading problem - ghost trigger
« Reply #5 on: February 27, 2010, 12:10:27 PM »
you have Disable Spindle Relays checked in ports and pins > spindle setup for the relay control.
uncheck it
see the comment above figure 7.1.2 in the threading on the lathe write up.

RICH

Re: lathe threading problem - ghost trigger
« Reply #6 on: February 27, 2010, 12:17:50 PM »
I had them enabled originally. Spindle RPM won't read unless they are enabled. I disabled them to try to eliminate all possible sources of the trigger the threading code is getting.

If I understand correctly, it should hang forever on g76 without a trigger.

It doesn't hang with or without the spindle relays enabled. It makes cutting passes as if it's getting a trigger, but it isn't getting one. Not from me, anyway.

Jeff
Re: lathe threading problem - ghost trigger
« Reply #7 on: February 27, 2010, 12:21:08 PM »
I have one sensor in my hall effect sensor. It has 3 wires: power, ground and sink. I get one pulse per pass with a magnet.

Offline RICH

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Re: lathe threading problem - ghost trigger
« Reply #8 on: February 27, 2010, 12:49:55 PM »
Well somewhere you must be getting an index pulse that Mach recognizes.

Turn off you controller and just  dummy run the code and you will see ( or should see ) that you get an error message
and the threading program won't run without an index pulse. So that would tell you that your software is working right.




Re: lathe threading problem - ghost trigger
« Reply #9 on: February 27, 2010, 01:41:32 PM »
It took me a little while to figure out I can't disable the estop input. I just assumed it worked when I clicked apply and closed the dialog. Mach3 must re-enable it somewhere along the way :)

With the controller off, I switched the estop input to active low so I could make a dummy run. It still appears to be getting a trigger. The wait for trigger led comes on then goes off half a second or so later, and the output shows it is making a threading pass. The index input is still mapped to the same input as estop (also active low). The index led never comes on.