Messages

71

General Mach Discussion / Re: MACH3 Soft limits problem

« on: April 15, 2009, 03:21:31 AM »

Hi Hood,
Very clear, better than manual explanations !!!
Please again to comment Safe Z.
At the moment I am not near to the machine and please explain to me where is the place to set it as  a "machine coordinate value."
And, is it -50 mm (minus 50) possible value?
Should I check Home neg. for Z axis?
Regards,
mrpeja

72

General Mach Discussion / Re: MACH3 Soft limits problem

« on: April 15, 2009, 02:20:21 AM »

Hi Hood,
Let's check if I understood:
For X axis (3500 mm travel) I would have Soft min as 10 mm and Soft max as 3490 mm
For Y axis (1600 mm travel) I would have Soft min as 10 mm and Soft max as 1590 mm
For Z axis (100 mm travel) I would have Soft min as -95 mm and Soft max as -5 mm
I would have Safe Z as -50 mm.
Is this OK?
What about Reversed, Home off. and Home Neg. columns?

BTW, is the improper Soft limits settings reason why Soft limits led on Run screen wont go ON and Soft limits are inactive?
mrpeja

73

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

74

General Mach Discussion / Re: Z axis drops down

« on: April 13, 2009, 02:45:39 AM »

Thanks Hood!
All ingenious thins are so simple!
mrpeja

75

General Mach Discussion / Re: Z axis drops down

« on: April 13, 2009, 01:59:23 AM »

Hi Hood,
I'd prefer a electromagnetic brake, because counterweight balance involves inertial load and spring balance requests more torque from the motor. But at this moment I'm not sure how to controll the brake.
When the machine is off, the brake must hold the axis, then when I turn it on, first the brake must be on, (releasing the axis) and then I do Homing. But at this moment axis will drop down!
I'm not sure what to do!
Maybe is better lowering the x axis slowly until it touches the material and then doing OFF the mach3 and the machine.
In this case (I suppose) I'll need to program this sequence. How to do this?
Please urgent help
mrpeja

76

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

77

General Mach Discussion / Re: MACH3 MOTOR TUNING

« on: April 11, 2009, 01:53:47 PM »

Hi,
I found jogging go slow because slow jog rate is set to 20%. When I jog holding Shift key then is going fast
mrpeja

78

General Mach Discussion / Re: MACH3 MOTOR TUNING

« on: April 11, 2009, 09:15:28 AM »

Hi Hood,
PROBLEM SOLVED!
First, I'm experienced electronics engineer and I can help about electronics, if somebody need.
I measured directly on parallel port, and frequency was like I said.
But  problem was on another place! I assumed when I jog, travel must be at maximal speed. But is not. I accidentally pressed Home axis bar and motor runs fast. So, I only need to find where to adjust jogging speed.
Thanks for your efforts to help me.
 Best regards
mrpeja

79

General Mach Discussion / Re: MACH3 MOTOR TUNING

« on: April 11, 2009, 01:52:50 AM »

Hi Hood,
No, I don't have microstepping. I have bipolar motor, working in half step mode. So, 400 steps per revolution and 0,9 deg per step.
It's urgent!
mrpeja

80

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