Messages

321

General Mach Discussion / Re: Rpm read out in mach 3 I

« on: April 24, 2022, 01:31:39 PM »

OK, assuming that the pickup is a Hall Effect device you shouldn't need much if any debounce.  (On the other hand if it's a reed switch then I suggest you use a hall device instead!)

I've recently switched to using UC100 motion controllers on my lathe and mill, but more importantly replaced the lathe motor with 3 phase and VFD.  Because this is much smoother I can now use the high speed range.  I soon found the rpm reading didn't work on high speeds as the debounce was set too long.  I just reduced it to something very short and the speed indicator works fine - so something to try?  I use a slotted disc and opto interrupter, and essentially there's no bounce at all so no need to debounce.

322

General Mach Discussion / Re: Rpm read out in mach 3 I

« on: April 23, 2022, 02:51:10 PM »

What spindle sensor are you using and what is the debounce parameter set to?

323

General Mach Discussion / Re: Homing acceleration in mach3

« on: April 23, 2022, 09:54:00 AM »

Have you tried changing the homing speed setting?

324

General Mach Discussion / Re: Homing acceleration in mach3

« on: April 23, 2022, 05:20:50 AM »

Go to config\homing/limits\ and see what speed% is set in the RH column.  The default in Mach3 is 20%, IIRC on my machines I have set it to 5%.  I think this multiplier works on both the homing speed and acceleration.

Again, how on earth can the machine anticipate when home will be reached when the object of homing is to find that point!  Usually there should be a slight overrun possible on the home switch so the overrun doesn't cause lost steps.   

325

General Mach Discussion / Re: Homing acceleration in mach3

« on: April 23, 2022, 03:34:20 AM »

How would you know when to start decelerating?

326

General Mach Discussion / Re: Homing acceleration in mach3

« on: April 22, 2022, 04:47:41 PM »

Since the point of homing is to find the limit switch and the machine doesn't know where that is, deceleration is not possible only a hard stop.  The homing speed is usually set to a few percent of the normal jog speed to minimise the overrun.

327

FAQs / Re: How do I mill a Perfect Circle?

« on: April 21, 2022, 01:50:54 PM »

Oh, and you may have backlash...

328

FAQs / Re: How do I mill a Perfect Circle?

« on: April 21, 2022, 12:35:45 PM »

It's very straightforward if you know the screw pitch, stepper-to-screw gearing, steps per rev (usually 200) and microstep ratio.  See the Mach manual.

Also try some back-and-forth moves from 0 to 100mm back to 0 say and make sure it always returns exactly to zero to check for lost steps.  Do you have a dial indicator for assessing exact stop position?

329

FAQs / Re: How do I mill a Perfect Circle?

« on: April 21, 2022, 10:49:56 AM »

Clearly not actually properly calibrated and possibly losing steps. Do the settings as a result of the autocalibration correspond to calculations?

330

General Mach Discussion / iPad as touch screen

« on: April 21, 2022, 06:51:23 AM »

As I'm now using Win10 to run Mach3 with external motion controllers I'm wondering about using a touch screen (as mentioned in another thread).  My son told me of a couple of iPad/PC apps that can make an iPad operate as an extension screen for the PC, and as I have an old iPad lurking somewhere this looks interesting.  However the solutions aren't free so before I tried one out I just wondered if anyone else had tried this and if it worked please?  An example is

https://www.duetdisplay.com/