Messages

7011

General Mach Discussion / Re: One step forward, two steps back.

« on: May 20, 2017, 07:31:00 PM »

Hi,
the choices are use an external motion controller which will allow you to use your PC as is OR change OS to 32 bit
Windows 7 or earlier.

Changing OS and using a parallel port it certainly doable, many CNCers do exactly this. The PP can be a bit cussed tho.
Some PCs do a good job when others don't without any particular reason. Additionally PP is VERY sensitive to other software
running on your PC, should your browser auto start say part way thru a machining job the PP will almost certainly stall
and lose the plot.

Given the sensitivity of the PP to PC and/or installed software provided the impetus for external controllers. There are a number
in the $100-$200 bracket that perform well. The companies making them have been around a while and back them up. Don't
buy a cheap-crap one from a no-name supplier, the forum is littered with posts from people who've bought such units and can't
get them to work.

Craig

7012

General Mach Discussion / Re: memory write error windows 10

« on: May 20, 2017, 07:14:03 PM »

Hi,
tell me more about this USB to Parallel converter. If you are trying to use Machs Parallel Port the converter won't work.

There are a number of external motion controllers which plug into the PC with USB but after all their internal trickery connect to your
BoB with a DB25 plug. All of these controllers will use a software plugin. Do you have this plugin?

Craig

7013

Mach4 General Discussion / Re: Jog Speed

« on: May 19, 2017, 03:21:32 PM »

Hi,
I don't know for sure but

rc = mc.mcJogSetRate(
      number mInst,
      number axisId,
      number percent)

suggests that the jog rate is assigned per axis.

Craig

7014

General Mach Discussion / Re: memory write error windows 10

« on: May 17, 2017, 06:29:43 PM »

Hi,
what external motion controller are you using?.

While Mach will run under Windows10 the parallel port driver will not. The parallel port will run under a 32bit OS Windows7 or
earlier. If you wish to use Windows10 as OS then you will require an external motion controller.


Craig

7015

Mach4 General Discussion / Re: Home, Limits, Soft Limits

« on: May 17, 2017, 01:20:37 AM »

Hi,
try

Mach4 CNC Controller
Mill Operations Guide

from page 40.

Reading your post you say that your limit switches are normally open. The most common method with Mach is normally closed.
Do the switches fitted have NC contacts in addition to the NO ones?

The ESS allows plenty of inputs so assigning one pin to each limit switch is doable but will require extra BoBs.
I would still recommend separate home switches. As your home switches reference your machine repeatability is desirable, I would
go for good quality roller plunger microswitches very securely mounted and adjusted. If your steppers or servos have index contacts
then you can use index homing as well for extremely accurate homing.

Craig

7016

Mach4 General Discussion / Re: Home, Limits, Soft Limits

« on: May 17, 2017, 01:02:54 AM »

Hi,
welcome aboard. The confusion over these terms is very common when starting out and can still catch you out years down the track.
A large part of CNCing is understanding these terms and being able to use them sensibly.

You may have noticed with Mach4 enabled on the file ops tab there is a button 'Help Docs?'. On that button you'll find a directory of useful
manuals and reference documents. Over a period of time you will probably find several other useful documents and they can be added to this
list, I have some for ENUMs and pound variables and more for LUA coding.

This one is useful

Mach4 CNC Controller
Mill Operations Guide

If your new to CNC then

CNC Programming Handbook by Peter Smid

is pretty much the bible for CNC.

The upshot is that when you turn a machine on the machine has no idea of 'where it is' unless you have some very expensive absolute linear encoders,
and if you had those 'why piss about' with Mach4 when you can afford Fanuc/Seimens? Consequently you need to home or reference  your machine.
Its common to use one extreme corner of the machining envelop as reference but is not in fact required. The simplest way to achieve that is to fit
microswitches, one to each axis, called home switches. When you home or reference your machine you will drive an axis until it triggers its home
switch, back up a little until it deactivates again, and set its 'machine co-ordinate' for that axis to zero. The next axis in the list will now be homed
in the same way. When all axes are homed the machine knows where it is and will maintain that knowledge throughout the session. It will know
for instance that its getting to very close to the end of travel on an axis and will fault out if you try to exceed the travel limit if you've set soft limits
correctly.

Most users fit limit switches as well, one at each end of an axis. If the machine tries to drive off the end of an axis it will trigger a limit switch and
go into emergency shutdown. Emergency shutdowns will often mean that the machine loses an accurate measure of its location and so restarting
the machine to continue with the job clamped in the vice may be out of whack and wreck the part. For this reason we try to avoid banging into the limits
whereas soft limits can be used and the machine can shut down and protect itself in a controlled manner and so that much easier to restart the
job if required.

Soft limits only work if the machine is referenced, its no good telling the machine 'don't go beyond 1000mm' if the machine doesn't know where it
started from. You can program Mach to know what the extents of your machine are, very useful. It will also warn you if the part program you've
just loaded exceeds your machine boundaries.

There are a number of techniques and tricks that can be used to reduce the number of switches and wiring by combining some functions together.
They can be confusing if your just starting out, I would recommend separate home switches but all six limit switches can be linked in series. While
even more comprehensive arrangements can be devised this one is reasonably simple to implement and understand and still offer good results if
soft limits are used intelligently.

Craig

7017

Mach4 General Discussion / Re: correct driver mapping

« on: May 17, 2017, 12:10:51 AM »

Hi,
welcome aboard.

Need a few more details before I could answer your question at least with reasonable certainty of being correct.

Usually Mach4/ESS assign the following:

Axis 0    Motor 0       X axis
Axis 1    Motor 1       Y axis
Axis 2    Motor 2       Z axis
Axis 6    Motor 6       Spindle    --note that axis 6 is the first 'out of band' axes available in Mach4, they can be motion controlled
                                               but not motion co-ordinated with other axes.
As to which pin to hook to which driver terminal will depend on the driver. Can you post the driver manual?

The most common setup is step/direction. Thus for each motor there would be two pins assigned, and if you use the ability to assign
aliases to pins engendered by the ESS plugin, XSTEP,XDIR for instance. Each pin would typically be connected to corresponding pul+
terminal of the driver with all the pul- terminals shorted together and hooked to 0V of the BoB.
The axis enable signal can be assigned using the ESS plugin, XENABLE for instance and that pin hooked to the enable terminal of the driver.

Much of these assignments depend on the driver, some are logic low, some logic high. While the wiring for each may be different they achieve
the same ends. Post your driver manual please.

Craig

7018

General Mach Discussion / Re: Purposly Making a Weak Spot

« on: May 16, 2017, 04:33:56 PM »

Hi,
looks like parameter 61 is motor rated torque. Set that to the nameplate torque.
Parameters 45 to 48 are percentage of rated max torques.
The 'internal torque' limits the maximum current within the torque control loop while the 'external torque'
limits the torque output of the torque control loop. Note it is possible that the output torque be limited to less than the
internal current command, it allows more dynamic control at the potential risk of loop instability.

Craig

7019

General Mach Discussion / Re: Step pulse

« on: May 16, 2017, 04:14:53 PM »

Hi,
they look like ordinary steppers to me. I think I would try a regular stepper driver, probably a Geko and see if it works, I suspect it will.
Thereafter conversion to Mach is straightforward.

Craig

7020

General Mach Discussion / Re: Step pulse

« on: May 16, 2017, 03:04:14 AM »

Hi,
I think Ger is right, you cannot program Mach to produce a 60us pulse.

You could make a circuit to do so if you wish. It would require one IC timer per channel, probably a simple 555 timer for cents each.

Do you mind me asking why its necessary to have such a long pulse? Do you require similarly extended pulses on other channels/axes?

Craig