Messages

201

General Mach Discussion / Re: Help wiring limit switch to servo tec board

« on: April 24, 2019, 08:43:19 AM »

You have an industrial controller so you should try something better than using 2 wires (mechanical) switches.

Attached is wiring for 3-wires  NPN and 3-wires  PNP sensors.

202

General Mach Discussion / Re: Random positioning motion on each operation start.

« on: April 23, 2019, 11:09:17 PM »

@extrapilot @kabover

I recommend you read concise STUDENT CNC GUIDE first
https://www.kth.se/polopoly_fs/1.686422.1550155780!/Student%20CNC%20Guide%20v0.4.pdf

Then
as RICH suggested
Mach3Mill_1.84.pdf that is available in this forum under USER DOCs.

203

General Mach Discussion / Re: Random positioning motion on each operation start.

« on: April 23, 2019, 10:57:29 PM »

Hey guys

Sorry if this has been covered- I have searched here and elsewhere and have not found anything.

On Mach3 Mill, I experience a random positional motion at the start of each operation in a file. Example- at start of program, on hitting Start, the table may be commanded to move to X7 Y2, but it may initially travel to something like X8.4 Y1, and then (if it has not hit soft limits) will move to the commanded position correctly.

I am doing nothing strange in my gcode, no Macros have been called etc, and this effect is seen on both .62 and .66 versions of Mach3.

Because the motion can be random for the same code (i.e. if I export only a single operation, and run that- I can see different directions of motion prior to the motion towards the correct start location), I don’t expect this is a gcode problem. In fact, the ‘random’ direction seems to be influenced by where the spindle is in relation to the operation’s starting point. It seems almost to generate some exponential vector, where if it is 1” from the target, it may travel 2”, but if 2” from the target, it may travel 4”…

It also seems to switch signs/direction if the starting position is on the opposite side of the starting position (i.e. if -X relative to the target, it tends to move in the +X direction, and vice versa). I don’t know if this is a hard rule- but it seems to be a pattern.

There is never a problem once the system begins the cut- I only see weirdness in Mach on the op start.

Below is some sample code which is doing this. It does it for all code I export, from all posts I have used. So, Im wondering if there is some bizarre config option in play, or if some registry corruption could cause the system to pull in random offset data as with motion in one coordinate system and then switching to G54 for the actual operation…

It is frustrating as hell, because this can and does cause tool crashes, and requires frequent re-zeros mid-program since a softlimit trip can yield a few thousandths bias…

Any thoughts are appreciated-

Rob

Code: [Select]

%
O0000 (Trunnion Test Part)
 (PROGRAM   - Trunnion Test Part.NC)
(DATE      - FEB-11-2018)
(TIME      - 1:36 AM)
(T120 -  3/8 FLAT ENDMILL    - H120 - D120 - D0.3750")
N110 (COMPENSATION TYPE - COMPUTER)
N120 T120 M06 ( 3/8 FLAT ENDMILL)
N130 G00 G17 G90 G54 A95. X7.5302 Y.6396 S3600 M03
N140 G43 H120 Z2.3295
N150 Z1.4295
N160 G94 G01 Z1.3295 F2.
N170 X7.4802 F3.17
N180 X3.5302
N190 G00 Z1.4295
N200 Z2.3295
N210 M05
N220 G28 A0.
N230 G90
N240 M30
%


1. The Gcode file says in comment
N110 (COMPENSATION TYPE - COMPUTER)

Does that mean the radius of tool#120 which has a diameter of 0.3750" (3/8") has not been compensated?
G41 that turns on radius compensation and G42 that turns off radius compensation are NOT found in the program so cut dimensions may be incorrect because of tool radius.

2. Operation.
Normally, you need to jog the machine to your work piece origin x and Y and Z (tool tip on top of the material surface), the in work coordinates (no red square around Machine Coordinates button) click [zero X] [zero Y] and [Zero Z].
Then click on [reg. toolpath]
BEFORE
you click on
[CYCLE START]

204

General Mach Discussion / Re: Random positioning motion on each operation start.

« on: April 23, 2019, 10:35:25 PM »

Brand new to this site, so please be kind. I too am having this same problem. It has occured for years now. In looking at the M6end macro I am questioning the second to last line:

Code"G00 X" & x & "Y" & y

Are the parenthesis in the correct position? Thanks

john f

Nothing wrong

205

General Mach Discussion / Re: UC400ETH soft limit problem

« on: April 23, 2019, 08:59:49 PM »

It is UC400ETH 5V TTL electronics that is randomly being affected by noise because of FLOATING input pins.

LOOK UP ANY ELECTRONICS BOOK.

If however the port2 is connected to another BOB that has opto-isolation ICs for the input pins, then it won't be necessary.

206

General Mach Discussion / Re: Ref All Home

« on: April 23, 2019, 08:45:34 PM »

But that is what the SLOW ZONE column is for.
In my case, I set it to SLOW DOWN when 20mm from the switches (see attached).
This only works if you ALSO set soft limits from 0 to say 1mm from the far end limit switch and the SOFTLIMITS is also on during program run.

Slow Zone slows the machine down when it approaches SoftLimits. It has nothing to do with homing.

That's like saying my car will stop at red lights by itself. But ONLY if you also apply the brakes.

I had already corrected myself.

[REF ALL HOME] is not done only once after powering up.
The first time, MACH3 may not know the machine zero YET.

After that, because of the presence of soft limits, if I do[REF ALL HOME] AGAIN and AGAIN, the SLOW ZONE will take effect.
I use [REF ALL HOME] whenever I want to change tools since my "machine zero" area ALWAYS does not have any material on top and I keep tool height always the same MANUALLY using a GAUGE relative to the machine surface by moving the the SPINDLE cylinder up and down by loosening and re tightening the clamp.
(I have to do this "NONSENSE" because I have end-mills that are 100mm long and tiny engraving bits that are just 20mm long but my Z travel is only 65mm so my spindle cannot be clamped at the same location all the time).

207

General Mach Discussion / Re: Ref All Home

« on: April 23, 2019, 06:58:40 AM »

Hi,
to my knowledge that is not how the slow zone works.

If you had an extra set of switches that activated 1/2 inch or so before the home switch you could make that work.

As reuelt has suggested the slow zone as allowed for in Mach applies only AFTER the machine is referenced and soft limits
are ACCURATELY applied.

Craig

YOU are correct. Sorry.
"Slow zone" is a soft limits feature.
The  std. v.062 Mach3 [ref all zero] VB script PROBABLY does not slow down based on slow zone. (I was using 066 before).
I have tried some better [ref all zero] scripts written by someone in this forum (sorry, can't remember who off hand).
It does [ref all zero] for each axis twice, first at high speed, backs off "the slow zone distance" and then does it again at much slower speed for a very accurate zero position before setting that axis to zero.

208

General Mach Discussion / Re: UC400ETH soft limit problem

« on: April 23, 2019, 05:41:00 AM »

Hi,

Machine always gets referenced but it is done outside of mach3 within the AC servo drives.

If Mach is not referenced (homed) then soft limits are out the window. If Mach does not know exactly where
machine coordinates 0,0,0 are then how do you expect it to know where  soft limits 500,500,200 (in machine coordinates)
is?

Craig

Craig,
Person who sold me the MC told me these:-
Router had No home switch(es) so:-
1. I must always power on and off at exactly the same point - to make that the machine x=0, y=0, z=0.
2. [Ref all zero] after powering sets the machine zero
3. Softlimits reference that Artificial machine zero.
4. Before shutdown, I must always execute
G90 (absolute units)
G53 (machine coordinates)
G28 X0 Y0 Z0 (go home)
to send the machine to the same "Artificial machine zero".
Then only I should power off the router.

When I power on the next day, machine will still ref the same "Artificial machine zero" which can be set to zero again [with ref all zero]


I found that too troublesome so I installed home and limit switches except for z--.
I could not have z-- limit switch because I always must move the spindle cylinder along it's mount to compensate for very long and very short bits.
So a block of metal is always used to set the bit height after manual tool change (moving the cylinder up and down). Then the lower soft limit will ALWAY prevent my bits from cutting the machine AL table surface.

209

General Mach Discussion / Re: Ref All Home

« on: April 23, 2019, 03:41:56 AM »

Craig: "What Mach wont do, without extra switches and programming, is go fast until it gets clos and then slow down."

But that is what the SLOW ZONE column is for.
In my case, I set it to SLOW DOWN when 20mm from the switches (see attached).
This only works if you ALSO set soft limits from 0 to say 1mm from the far end limit switch and the SOFTLIMITS is also on during program run.

I tried changing the 'slow zone' but I could not get it to work. Maybe my 'soft limits' are not set correctly.

Study my limit switch settings and set to suit you machine size. SLOW ZONE also works for manual jogging using 360games pad.
When you make a fundamental change, please save the settings and restart Mach3 before you can confirm it working or NOT.
DO NOT TURN OFF SOFTLIMITS before restart or it will not work.

210

General Mach Discussion / Re: Ref All Home

« on: April 23, 2019, 03:29:03 AM »

Craig: "What Mach wont do, without extra switches and programming, is go fast until it gets clos and then slow down."

But that is what the SLOW ZONE column is for.
In my case, I set it to SLOW DOWN when 20mm from the switches (see attached).
This only works if you ALSO set soft limits from 0 to say 1mm from the far end limit switch and the SOFTLIMITS is also on during program run.