Topics

21

General Mach Discussion / Torch referencing

« on: May 04, 2009, 01:30:05 PM »

Hi,
I made G code file using THC300-G31 post processor.
I expected to see torch referencing before every hole (hole diameter 45 mm), like is stated in post processor abstract:
"The torch is referenced at cut start and every 500 mm of movement thereafter"
But I didn't see was I expected.
Instead, referencing occurs from time to time, and below is a sample of G code.
I want referencing before every cut, so, before every M03 macro
How to achieve this?
mrpeja

Code sample
N0120 (Process: Plasma,  0, Plasma, 2 mm kerf)
N0130 M06 T2  (Plasma, 2 mm kerf)
N0140 G00 Z50.0000
N0150 X1618.6000 Y726.4000
N0160 Z5.0000
N0170 G31 Z -100 F500.0
N0180 G92 Z0.0
N0190 G00 Z4.0000
N0200 G92 Z0.0
N0210 G00 X1618.6000 Y726.4000 Z5.0000
N0220 M03
N0230 G04 P0.5
N0240 G02 X1620.5676 Y726.0900 Z3.0000 I0.0000 J-6.4000 F1000.0
N0250 X1625.0000 Y720.0000 I-1.9676 J-6.0900 F960.0
N0260 M667 (THC on)
N0270 X1625.0000 Y720.0000 I-15.0000 J0.0000 F1500.0
N0280 M666 (THC off)
N0290 X1618.6000 Y713.6000 I-6.4000 J0.0000 F960.0
N0300 M05
N0310 G04 P15
N0320 G00 Z50.0000
N0330 X1418.6000 Y726.4000
N0340 Z5.0000
N0350 M03
N0360 G04 P0.5
N0370 G02 X1420.5676 Y726.0900 Z3.0000 I0.0000 J-6.4000 F1000.0
N0380 X1425.0000 Y720.0000 I-1.9676 J-6.0900 F960.0
N0390 M667 (THC on)
N0400 X1425.0000 Y720.0000 I-15.0000 J0.0000 F1500.0
N0410 M666 (THC off)
N0420 X1418.6000 Y713.6000 I-6.4000 J0.0000 F960.0
N0430 M05
N0440 G04 P15
N0450 G00 Z50.0000
N0460 Y526.4000
N0470 Z5.0000
N0480 M03
N0490 G04 P0.5
N0500 G02 X1420.5676 Y526.0900 Z3.0000 I0.0000 J-6.4000 F1000.0
N0510 X1425.0000 Y520.0000 I-1.9676 J-6.0900 F960.0
N0520 M667 (THC on)
N0530 X1425.0000 Y520.0000 I-15.0000 J0.0000 F1500.0
N0540 M666 (THC off)
N0550 X1418.6000 Y513.6000 I-6.4000 J0.0000 F960.0
N0560 M05
N0570 G04 P15
N0580 G00 Z50.0000
N0590 X1618.6000 Y526.4000
N0600 Z5.0000
N0610 G31 Z -100 F500.0
N0620 G92 Z0.0
N0630 G00 Z4.0000
N0640 G92 Z0.0
N0650 G00 X1618.6000 Y526.4000 Z5.0000
N0660 M03

22

General Mach Discussion / Floating head switchoffset

« on: April 30, 2009, 10:02:52 AM »

Hi all,
finally my floating head works fine. But I spent three days for this, until I realise what switchoffset really is.
I mentioned this is the travel between moments when switch is on and off, usually 0,5 - 1 mm.
But it isn't.
It includes complete travel of floating head holding plate, from the moment when torch touches material, to the moment when switch is activated. In my case - 16 mm.
I suppose I didn't precisely understood the explanations and texts I got. (I newer learned English in the school),
Thanks to everybody who helped me
mrpeja

23

General Mach Discussion / Soft limits problem, still confused

« on: April 27, 2009, 05:54:57 AM »

Hi Hood,
I must ask for help again.
I use plasma table with THC300, and SheetCam postprocessor Plasma THC300 - G31 - corner slowdown.post.
I home my Z axis torch carriage at the top position. Z axis travel is 100 mm
When I start the cut, Z axis goes up, touch the limit switch and this is the end!
I see in generated G code the first instruction is to go UP 50 mm (my safe Z position).
I've been advised to insert snippet code: G31 Z -100 F500 and to set Soft max to 60 mm, Soft min to -50 mm and Home offset to 60 mm and Auto zero checked. Pretty confusing for beginner like me!
Sometimes it works, but sometimes, when I load another G code file,  I get Soft limits warning when I start cutting, and question to proceed or not.

Actually, don't knew where to look to find problem source.

I have idea install another limit switch and to home down to find zero position. And without code snippet.
Please advise.
BTW, What exactly is mentioned with those three lines of code: (I selected mm for my units, NOT inch)
N0040 G53 G90 G40
N0050 F1
N0060 S500
mrpeja

24

General Mach Discussion / THC300 jumps up down

« on: April 19, 2009, 11:52:08 AM »

Hi,
I just started cutting a straight line for testing. I see torch goes all the time up and down for small amount and Up and Down leds goes on and of 2 to 3 times per second. The cut is not ideal. Material is 4 mm steel, and 60 amps
What to adjust in this case?
Miroslav

25

General Mach Discussion / THC300 postprocessor mistake???

« on: April 18, 2009, 12:01:01 PM »

Hi all,
I knew it's weekend, but I need urgent help.
I have set my plasma machine Z axis as follows:
Z limit switch is on the top. Soft Max limit is 0, and soft min limit is -100, Home neg. checked.
Safe Z is 50 in machine coordinates.
When I start Homing, Z axis goes up to the switch, then down and stops to the limit sw off. Soft limits button works.
But when i start cutting process, Z axis goes up, touch the limit switch and Mach3 resets!
It stops at line N0110, (see below) and It reports Limit sw error.
In SheetCam I use Plasma THC300-G31-Corner slow down. post
I'm confused about how to solve this problem, what is configured wrong, or why post processor generates N0110 line. Is it possible SheetCam knows about Z safe coordinate?

Miroslav

N0000 (Filename: 30kwProba1.tap)
N0010 (Post processor: Plasma THC300 - G31 - corner slowdown.post)
N0020 (Date: 16.4.2009)
N0030 G21 (Units: Metric)
N0040 G53 G90 G40
N0050 F1
N0060 S500
N0070 M666 (THC off)
N0080 (Part: 30kwProba1)
N0090 (Process: Plasma, 0, plasma 3mm)
N0100 M06 T1 (plasma 3mm)
N0110 G00 Z50.0000
N0120 X1011.3000 Y1378.2000
N0130 Z5.0000

26

General Mach Discussion / MACH3 Soft limits problem

« on: April 14, 2009, 05:30:06 PM »

Hi,
I use Mach3 and THC300. My machine has X axis 3500 mm, Y axis 1600 mm, Z axis 100 mm.
Have common switches on all axes for limits and home and separate switch for floating head. When I do Homing, X and Y axes go left and down, respectively. Z axis goes up. Should I zero all DROs?
But Soft limits led won't go On (I have soft limits set) and don't work.
How to set those parameters?
Should I set Auto zero?
How Mach3 knows where is top of material when it goes to safe Z?
Should Z DRO shows negative numbers?
I'm confused and need detailled explanation how to set all parameters.
mrpeja

27

General Mach Discussion / Z axis drops down

« on: April 12, 2009, 04:17:36 PM »

Hi,
My plasma table finally runs (not yet cuts).
I have Z axis with toothed belt and pulley.
There is new problem: when Mach3 ends (File>Exit), or if I press Reset button Z step motor is disabled and Z axis with plasma torch immediately drops down.
Any idea how to prevent this drop?
mrpeja

28

General Mach Discussion / MACH3 MOTOR TUNING

« on: April 10, 2009, 02:02:50 PM »

Hi,
There is a situation:
I have plasma table, step motor 400 steps/rev, gear ratio 1:5 and rack and pinion 30 mm pitch diameter. Here is my calculation:
400 * 5 = 2000 steps/revolution of pinion,
path per one revolution of pinion: 30 * pi = 94,347779 mm
path per step: 94,347779 / 2000 = 0,0471 mm.
steps per unit (mm): 1 / 0,0471 = 21,22.
So far so good.
Now Motor Tuning in Mach3:
I put 21,22 steps per unit (mm), and velocity 4000 mm/min (what is 66,66 mm/sec)
Step frequency will be 21,22 * 66,66 = 1414 Hz
But motor run to slow and oscilloscope measurement shows step frequency about ten time slower, e.g. 135 Hz!
Who is mistaking, me or Mach3?
PLEASE CONTROLL MY CALCULATION
Regards,
mrpeja

29

General Mach Discussion / Home, machine, and work coordinates

« on: March 30, 2009, 02:48:29 PM »

Hi Hood,
Here is one actual question:
I have plasma table 3,5 x 1,8 meter travel, limit switches at both ends.
Z axis 150 mm travel, with Floating head, floating switch and home/limit switch at one end.
I want to cut on sheet 3 x 1,5 meter, and sheet should be somewhere in the middle of the table.
Please explain what will be the home position, machine coordinates, work coordinates.
Please explain how to set each of them and how to remember all for further work.
Should SheetCam be involved in this process?
Please have on your mind, I'm a newbie,
Regards
mrpeja

30

General Mach Discussion / Z axis jogging, Mach3

« on: March 27, 2009, 05:55:29 AM »

Hi,
Why Z axis step jogging doesn't work with THC300SM3 profile?
It works with default Plasma profile
mrpeja