Topics

11

General Mach Discussion / Read and write to Z DRO?

« on: October 07, 2016, 06:32:23 AM »

I'm playing around with touch probe automation. Everyone else does, so why not.

Anyhow, I want be able to zero the Z DRO directly, from within g-code, without using a macro. I know that some OEMDROs are mapped into vars, but I cannot find any reference to the on-screen DROS.
What I want to do is to write something like

#15802=0 and have the current Z DRO go to zero.

Am I out of luck?

PS: yes, I can do it with a macro. Yes, I can do it with several instructions using one of the work spaces. But I want to do it in one line.

Cheers
Roger

12

General Mach Discussion / Improved g83 macro with bug fixes (I hope)

« on: August 10, 2016, 07:07:46 AM »

The really slow speed of the G83 instruction in Mach3 Lathe bugged me so much I had to try to fix it.
See attached for my new version - you will have to rename it to M1083.m1s of course. I would welcome test results.
(It works fine for me, but I recommend some air cutting first.)

There was a line of code missing in the version in the .062 kit, to do the rapid feed down to near the last drill depth. Without this instruction the Z axis crawled along at G1 speed the whole way, each time. I have fixed this.
I have also tidied up the code a bit. There is still one wierdo in there which I do not understand, but it does nothing.

Now, this is for the lathe, so it ASSUMES that X=0 and ignores any X value you might provide. I suggest you move to X=0 BEFORE you use this macro. If you really want, a move to X=0 could be inserted in the macro, but I strongly prefer that such moves be explicit, so I know when they are going to happen.

Cheers
Roger

13

Show"N"Tell ( What you have made with your CNC machine.) / Rotary Table for A axis

« on: May 29, 2016, 07:01:18 AM »

5" rotary table for A axis, using a 50:1 shg-25-50-2uh harmonic drive (second hand from Korea, via eBay).
Shown here machining pulleys for GT2 belts.

Cheers
Roger

14

General Mach Discussion / Rotation radius or diameter? for display

« on: April 25, 2016, 03:40:03 AM »

I am playing around milling out GT2 pulley teeth with a 1.2 mm ball end mill and a rotary table (A axis).
(Mach3 .062, ESS, W7, 1024.set)

Pass 1 digs out the main groove: fine.
Passes 2, 3 & 4 round off the sides of the groove with the side of the cutter, in little steps. For this to work the pulley has to be rotated and the cutter offset sideways a bit. The whole idea works OK (but needs values to 0.01 mm).

BUT
Getting a display which resembles what the job looks like has been difficult.
Obviously the A axis has to be enabled.
Note that the Z=0 point is on the surface of the object being machhined, not on the A axis CL. So the Rotation Radius for the A axis on the Settings page has to be non-zero - that works too.

But what value to put in the DRO? Radius, or Diameter?

Many years ago there was a so-called bug fix which changed the label on the DRO from 'Rotation Diameter' to 'Rotation Radius' in order to get the surface cutting speed working correctly. However I don't care about the surface speed. All I would like is a credible display.
But if I enter the radius the display is pretty awful, and does not look what I am doing (but the machining works).
If I enter the diameter the display looks accurate (wrt the real world) and the machining is fine.

Does anyone know whether the bug fix was only partial: surface speed was fixed but not the display component? That would explain my problem.

Cheers
Roger

15

General Mach Discussion / Blank Tool Path Display

« on: February 13, 2016, 11:39:25 PM »

Hi All

I have just spent some time trying to see the tool path on the standard screen. It was missing. No Tool Path!  Aaarrgghh!

But first some background:
Win7, ESS, Mach3 .062, NO other jobs running.
I have been working on a vacuum table for PCBs. The table has to handle al sorts of shapes and sizes, so the trad 'grid of grooves with an O-ring' is not really suitable. OK.
Part of the development involved probing across the surface of the table to see how many microns it was tilted or whatever. So there were some rather long probing sessions going on.
But my (MYOG) kinematic probe is not super reliable: the shape of the contacts is wrong. Once in a blue moon it would not reseat on retraction, so the g31 command could freeze, or it could send the Z axis through the roof.

After the last hiccup I had no tool display. Yes, all the right check boxes were ticked. Yes, test programs would run. But no tool display.

Eventually, wandering around sobbing, I came across the less-frequently visited Offsets screen. The current Z axis DRO said 0.000 - I had reset it after rescuing the spindle from the stratosphere.  BUT the box in the top right hand corner with the machine coords button was showing a Z DRO value of ... several million? Ah - that can't be right. Zeroing that just transferred the millions to the current DRO. I zeroed the current DRO and then did a Ref All Home (tall thin button). Now I had 0 on both DROs.

And lo and behold - the tool path display was back!

No idea what the Mach3 code is doing, but it's something to check every now and then.

Cheers
Roger

16

General Mach Discussion / M9999

« on: October 20, 2015, 06:31:02 AM »

Way back in 2009 there was some discussion about a macro m9999 which would allow

#3=3
o100
G0 X#3
#3=[#3+1]
M9999 (If (GetVAR(3) > 6) Then Code" (END M9999)" Else code"M98 P100 " )
m30
%

But of course this gets thrown out because it has a nested comment (or two or three).
It's also recursive, which might upset Mach3 something awful!

Did this ever come to anything?

Cheers
Roger

17

General Mach Discussion / Difference between Enable Pins and Output Pins?

« on: June 05, 2015, 10:58:22 PM »

Hi all

I am trying to put some safety interlocks into my system, which combines lathe and mill. Without some interlocks, eStop in mill mode briefly spins the lathe chuck - that can be a bit too exciting.

So my idea was to use Enable #1 to activate a relay between the spindle PS and the mill spindle, and to use Enable #2 to connect spindle PS and lathe chuck. There is a HARDWARE interlock preventing both from being activated together. That interlock works.

But what has me seriously confused is that it seems that Enable1 - 4 ALL activate when I hit Reset: the red LEDS on the diagnostic panel all turn on in sequence. That happens regardless of whether they are meant to be Active Hi or Lo. I can then DeActivateSignal(Enable1) and so on of course. However, Enable5 and Enable6 do not do this. I have not been able to figure out the difference yet.

Question: are these enables MEANT to go active on Reset? If so, they are obviously not what I want. I will have to use Output#1 etc instead.
I cannot find anything in the manuals about how either the Enable pins or the Output pins work or differ.

The alternative, of using the inversion of the Enable pins, is not good: that would enable things when eStop happens. Oops!

Cheers
Roger

18

General Mach Discussion / Jog A axis from KB, and Zero A axis from Program Run page

« on: January 23, 2015, 07:01:13 AM »

Two questions about the A axis controls (stock 1024.set screen)

Is there a (pair of) keys to jog the A axis back and forth on the Program Run page? I am sure there ougjht to be, but I can't find it .

I can zero the A axis DRO on/via the MDI screen, but in the Program Run screen the Zero 4 button does nothing. How to activate?

I am sure this has been discussed and explained before, but i cannot find it.
Cheers
Roger

19

General Mach Discussion / Can Mach run a macro when eStop is triggered?

« on: November 24, 2014, 05:38:55 PM »

I'm rebuilding the electronics on my CNC. S far so good, but I would love to add a safety feature.
When you hit Reset, the Init string is executed. This can include G-codes and M-codes.
Is it possible to have Mach execute a string when eStop is triggered?

To explain:
My CNC is a sort-of dual function machining centre. It has a good vertical milling head, but it also has a horizontal lathe chuck. The config is a bit like those small lathes with a mill/drill over the chuck, but somewhat more stable. Only one spindle can be used at a time of course.

Now, in the past, a changeover relay was used to select whether I was milling or turning. However, when an eStop was triggered with one spindle spinning, the C/O relay could drop out and spin the OTHER spindle for a moment, while the spindle power supply shut down. This was mildly exciting at times.

I have changed this to have use DP relays, with logic interlocks. To use the mill Mach energises the mill relay in the Init string. To use the lathe Mach energises the lathe relay. The sytem cannot energise both at once. All the same, I would love to have Mach release whichever relay was energised when an eStop happens. I do not want to kill the Charge Pump however: that causes too many hassles. So, can I define a string to be run when eStop is triggered?

(Yes, I could do this with external logic linked to the eStop line.)

Cheers
Roger

20

General Mach Discussion / M90 and M91, and parameters to M codes

« on: November 23, 2014, 04:25:20 AM »

Hi all

Three related questions:

Does anyone know whether Mach3 supports M90 output #n and M91 output #n calls? Some systems allow you to turn on and off an output #n this way.

Alternately, is it possible to pass a parameter to an M-call? eg M90 3 - which will be translated internally to ActivateSignal(output3) if I can figure out how to get the '3' into the string in an acceptable manner.

Finally, the Reset/Init string defined in Config - can one include an M-call in that string? All I ever see are g-codes.

Cheers