Messages

2041

General Mach Discussion / Re: Limit tripped but nowhere near switch?

« on: September 13, 2019, 05:08:07 AM »

Hi,

Does mach3 or perhaps the control board have a builtin feature where the limit will trip if the tool encounters too much resistance?

No, Mach3 does not do that.

My guess is that electrical noise is getting into your limit switch wiring.

In the first instance you need to fit line filters and/or line reactors to tame the noise from the spindle.
Thereafter look to shielding your signal wiring, load the signal lines with an impedance chosen to damp noise optimally.

Most beginners spend all sorts of trouble shielding and filtering signal lines without ever considering reducing the noise output
of by far and away the noisiest (electrically) component....the spindle.

Craig

2042

General Mach Discussion / Re: Motor tuning, please take it easy on me I'm new to this :)

« on: September 11, 2019, 05:36:08 AM »

Hi,
the graphs are representative only, that they will exactly describe every motor is fallacious.

Also note that the 33% retained torque at 1000 rpm was measured with a driving voltage of 60V, the result
might be closer to 50% if you used 80V.

These motors are still many fold better than what you had. Try them out.

Craig

2043

General Mach Discussion / Re: Motor tuning, please take it easy on me I'm new to this :)

« on: September 11, 2019, 04:48:58 AM »

Hi,

Torque is the motor torque in Nm.
Pulse rate?
400 pulse rev?

The driver in this measurement is set to half stepping, that is 400 pulses per rev as compared to 200 pulse per rev for
full steps. Thus 400 pps (pulse per second) is 1 revolution per second. So 1000 rpm is equivalent to (1000/60)x400=6666 pps.

Pulse per second(half stepping regime)= RPM/60 X400

Torque at low rpm =5.5Nm = 3.7ft.lb =718 oz.in
Torque at 1000 rpm (6666pps)=1.8Nm=1.2 ft.lb=235 oz.in

Ratio of torque @1000rpm compared to 0 rpm =1.8/5.5 =33%

Craig

2044

Mach4 General Discussion / Re: Recommendation for VFD Alarm functionality?

« on: September 10, 2019, 10:06:07 PM »

Hi,
many servos and VFDs require an alarm reset usually provided by the controller.

If the controller cannot be enabled because of a VFD alarm and you cannot clear the alarm until
the controller is enabled......

Craig

2045

General Mach Discussion / Re: Motor tuning, please take it easy on me I'm new to this :)

« on: September 10, 2019, 08:04:18 PM »

Hi,
changing the microstepping will marginally affect smoothness but will have no effect on stepper torque and therefore acceleration.
Lower microsteps will bring the required pulse frequency down and allow you to go faster at 25kHz kernel or alternately increase
the kernel speed to as much as your PC can handle.

If you use an ESS then it so fast that kernel speed is irrelevant and is worthwhile aside from being smoother motion and the PC very much
less inclined to stutter and stall.

To really effect an increase acceleration without losing top speed you need a gear or belt reduction of 2:1 to about 4:1.
If that does not appeal try direct coupling to the screws first. If that's adequate all well and good. If you want more torque
at speed and maintain your top speed a belt reduction may well be the only way to achieve it.

I understand the test, would you just manual jog (at full velocity) one axis at a time back and forth between the limits or create a program to interpolate both axis running together for X and Y?

You need to create a program that goes back and forth multiple times but only one axis at a time.
g0 x0 y0 z0
g0 x100
g0x0
g0x100
g0x000
g0x100
g0x0
etc...

Try a low acceleration and work up, I should suggest a large increase to the extent it stalls in acceleration phase then back off.
You don't want or need to take all day over this, be reasonably aggressive in your increments and narrow the increments as you establish
the outer limits and refine you guesses.

Craig

2046

General Mach Discussion / Re: Go to Zero extremely slow, please help

« on: September 10, 2019, 03:00:55 PM »

Hi,
when Mach starts it defaults to a low 6% of max speed.

You can change that by including an F********* word in the initialization string that runs at startup.

Craig

2047

Mach4 General Discussion / Re: Recommendation for VFD Alarm functionality?

« on: September 10, 2019, 02:44:07 PM »

Hi,
that depends on the nature of the alarm.

If the VFD is just getting hot then a <feedhold> would be fine, the motion stops and therefore the cutting load drops
and allows the VFD to thermally recover.

If however the alarm is over-current or over-voltage the VFD will shut down and the tool will stop. If you don't stop
the motion of the machine immediately the machine will snap the tool and/or wreck your work and/or work holding.
An Estop is appropriate. A Delta VFD can have several alarm outputs....you could and probably should have more than one
with actions appropriate to each.

Craig

2048

Mach4 General Discussion / Re: Mach4 bug (wizards) - v 4.2.0.4305 + 4300

« on: September 10, 2019, 02:34:22 PM »

Hi,
at a guess I would say that the Wizards were compiled with Lua 5.2 compiler whereas Mach4 progressed to the Lua 5.3
compiler about four months ago.

Craig

2049

Mach4 General Discussion / Re: Mach 4 keyboard increment jogging randomly swaps to inches?

« on: September 10, 2019, 02:26:10 PM »

Hi,

Is this a known problem? or any ideas what could be causing it?

Yes there has been a few threads discussing that problem, the last about four months ago. Smurph promised he would
have a look at it for the next build and I've not heard of it since so I assume he looked at the problem and resolved it in
the latest builds.

What build Mach4Hobby are you using?

Craig

2050

Mach4 General Discussion / Re: Recommendation for VFD Alarm functionality?

« on: September 10, 2019, 02:21:38 PM »

Hi,
just hook an input pin of the ESS to the alarm  output of the VFD. Logically connect that input to an unused Mach input
signal, ISIG_INPUT50 say, and put this in the SigLib table in the screen load script:

Code: [Select]

[ISIG_INPUT50]=function(state)
if (state==1) then
    mc.mcCntlEStop(inst)
end
end,
Substitute <feehold> or <cyclestop> for Estop as you wish.

Craig