Messages

1481

Mach4 General Discussion / Re: Switching from Mach 3 to 4 - How Do You Change Motor Tuning Time

« on: May 11, 2020, 06:16:09 PM »

Hi,
I have experimented with changing the speeds and it seems that the display is restricted to 4sec.

Remember that that is just a visual representation of the time/velocity diagram, not necessarily a practical movement.

My new build mill for instance travels 350mm (the X axis travel) in 1.6 seconds including both  acceleration and deceleration
phases, thus my machine will NEVER perform a G0 move of 4 seconds duration, and if it attempts to it will crash BIGTIME.

Craig

1482

Mach4 General Discussion / Re: Mach 4 and 5 Axis CNC

« on: May 11, 2020, 06:07:50 PM »

Hi,

1. If someone could suggest a good controller board for a 5 axis CNC (Mach4), that can control x y z and 2 rotary axes, along with spindle control.

Arguably the Ethernet SmoothStepper (Warp9 TD) is the most complete (step/direction) Mach4 ready motion controller, certainly in the value end of the market, $180. You'd
need to pair that with one or more breakout boards, the C10 ($23) is bidirectional with one port (17 IO's), the C25 ($30) with two ports (34 IO's) are simple
and cheap whereas the MB3 ($180) (CNCRoom) has three ports developed (51 IO's) replete with both differential and single ended 24V IO's, opto-isolated inputs, spindle control
features like PWM-to-analogue etc.

2. We are currently thinking of using Nema 34 stepper motors, any suggestions in changing these motors or keeping them would be taken into consideration.

Many people make the mistake of choosing 34 size steppers because of their great torque specs, say 1000 oz.in and higher. These steppers have high inductance and perform
VERY BADLY at speed. Avoid like the plague!

All steppers lose torque the faster they go and the winding inductance determines how badly the torque will roll off with speed. The lower the inductance the better.
With a 23 or 24 size stepper you want 1-2mH, 1mH preferred and reject anything over 2mH.
With a 34 size you want 2-4mH, 2mH preferred and reject anything over 4mH.

Many users have found low inductance (1-1.5mH) 23 size steppers of 350-400 oz.in outperform (overall) 34 size steppers by virtue of 34 size steppers greater inductance.

The classic means of counteracting the inductance of the windings is to use the highest possible driving voltage. The effective practical maximum at this time is 80VDC.
Gecko drivers are the gold standard for reliability but are not cheap. Leadshine AM822's for example are also 80VDC capable and half the price.

Transformer/rectifier/capacitor type power supplies are recommended over switch mode types by virtue of their superior overload capacity.

Craig

1483

Mach4 General Discussion / Re: How to read/write Analog Inputs and Analog Outputs

« on: May 11, 2020, 04:16:26 AM »

Hi,
I can't find that API in API.chm, neither does it come up in ZeroBrane.

Craig

1484

Mach4 General Discussion / Re: How to read/write Analog Inputs and Analog Outputs

« on: May 10, 2020, 11:27:35 PM »

Hi,

if I wanted to Read "Analog Input #1"  ..................then what would i use ?
if I wanted to Write "Analog Output #1"  ...............then what would i use ?

To my knowledge there is no such thing as 'Analog Input #1' or 'Analog Output #1'. You could certainly define registers like that
under iRegs0 for instance.

Your examples Output#1 and Input#1 are Boolean signals whereas an analogue value is a number and requires a register not a signal.

Craig

1485

Mach4 General Discussion / Re: How to read/write Analog Inputs and Analog Outputs

« on: May 10, 2020, 09:21:37 PM »

Hi,
the analogue values are stored in registers. The individual registers are 'owned' by the PoKeys board.

If you go to the Register Diagnostics page and expand the PoKeys register tree you will see the registers you require.

To read the value first you must get the handle of the register using mc.mcRegGetHandle() and then read the value with
mc.mcRegGetValue or mc.mcRegGetValueString().

Craig

1486

Mach4 General Discussion / Re: Switching from Mach 3 to 4 - How Do You Change Motor Tuning Time

« on: May 10, 2020, 08:57:15 PM »

Hi,
that is not a setting per se. The Mach4 motor tuning graph shows a velocity/time graph of the motor as it accelerates at max accel to max
velocity and then decelerates at max accel. The time scale is a convenient means for you to establish the time spent at each phase.


Try for instance to drastically increase the acceleration and see what happens to the time  scale. Try also much higher and lower max velocities and
see how the time scale varies.

Craig

1487

General Mach Discussion / Re: hard switches not working when program running in mach3

« on: May 08, 2020, 08:51:09 PM »

Hi,
when a Gcode program is running or when in <FeedHold> the motion controller is under the direction of Machs
trajectory planner whereas the buttons are part of Machs GUI, which is suspended.

In order for a button to be recognised is for the button or input to be 'polled' on a regular basis, aka the MacroPump
as Graham has suggested. Every 100ms or so the code in the macro pump is run and it will specifically check all of
the inputs in sequence and act on any it finds active.

Another alternative that achieves the same result is to use a Brain. It to is a bunch of code that runs on a regular basis
and can cause specific machine behaviour in response to an input.

Craig

1488

General Mach Discussion / Re: Mach3 and interface 5 axis

« on: May 08, 2020, 04:59:31 PM »

Hi,

Are you using, or wanting to, Mach4 or Mach3?

The screen shot of your kit suggests that the breakout board supplied with your kit is just a simple and plain
parallel breakout board. This requires that Mach (either 3 or 4) use a parallel port motion controller.
That in turn places certain restrictions on the PC, in particular the PC MUST be 32 bit Windows7
or earlier and laptops don't work.

The software driver that enacts Mach3's parallel port is free with Mach3. Mach4 has a parallel port driver
called Darwin but a $25 license fee applies. Note also that Darwin misses on a number of realtime supports
like lathe threading and THC. Darwin was intended to be a cheap way to experience Mach4 but not intended
to be capable of exploiting all of Mach4's power. In reality Mach4 was always intended to be paired with an
external motion control board.

If you want to use Windows 10 or any 64 bit OS or a laptop then you will require an external motion controller like
an Ethernet SmoothStepper or a UC300.

Craig

1489

Mach4 General Discussion / Re: Mini Computer to Run Mach 4 and PMDX?

« on: May 08, 2020, 12:46:22 AM »

Hi,
my machine run ons a dual core Atom mini-ITX single board PC with on-chip graphics. It wouldn't 'pull the skin
off a rice pudding' yet it runs an Ethernet SmoothStepper and Mach4 very well.

The only time I notice the low power of the CPU is when I go to load large files, say 5MB or bigger. It takes quite a while to
load and draw the first tool path, thereafter its fine.

Mach4 is not  a hungry program, even a very modest PC will run it fine. Don't waste money on a 'you beauty' PC, you'd be better
off spending a bit more on that next spindle....or tools....or servos...or ballscrews ...or....

Craig

1490

Mach4 General Discussion / Re: Recommend me a high quality MPG Wheel?

« on: May 07, 2020, 07:09:06 AM »

Hi,
I use a VistaCNC P1A pendant...it has its own USB plugin and works well. I didn't have to shag around making
my own.

Whether it could be said to have as nice an MPG as you describe....I don't know, I certainly like it.

Craig