Messages

2101

Mach3 under Vista / Re: Origin drifting along the program running

« on: August 19, 2019, 11:38:29 PM »

Hi,
you are gaining or losing steps. If it were the servo/servo drive it would fault 'following' error in short order.
Ergo the extra/missing steps ocurr before the servo drive.

The ESS is likely to be good. I assume that you have a breakout board between the ESS and the servo drive.
What make and model? Is it fast enough for the signals it is expected to carry?

What is your motor tuning (steps/unit and max velocity)?

What are the electronic gearing parameters in the servo drive?

All these questions determine the required signalling pulse speed to the servo drive. Personal experience suggests that
any thing faster than 50-100 kHz is going to require differential signalling.

Craig

2102

Mach4 General Discussion / Re: Could somebody just spell it out for me?

« on: August 18, 2019, 05:17:04 PM »

Hi,
if you stick with 32bit Windows7 or earlier you could use Mach4s parallel port called Darwin ($25 licenec fee applies). It works OK
but is limited in realtime supports like threading and THC.

To get the best out of Mach4 you need an external motion controller. You have mentioned two already. With an external motion
controller you can use a 64bit OS like Windows10.

Not all Mach4 ready controllers are the same....some have more realtime supports than others. At the current time the
Ethernet SmoothStepper by Warp9 has the most complete set of realtime supports including threading, spindle PID,backlash comp,
realtime THC, laser rastering plus all the usual homing/limits supports that you would expect.

May I suggest you look at:
Ethernet SmoothStepper by Warp9
UC300 by CNCDrive
57CNC by PoKeys
PMDX-424 by PMDX
Hicon Integra by Vital Systems ($600 entry level)
CSMIO/S by CSLabs (600 Euro entry level)

Note the UC100, PMDX-411 and 57CNCdb25 are all 'one port' devices and have strictly limited inputs. They are cheaper than their
bigger siblings but you'll miss the extra IO. If you do want a UC100 DON'T buy a Chinese rip-off from EBay or Amazon, they are
NOT the real thing. Buy direct from CNCDrive or their nominated distributor.

Craig

2103

Mach4 General Discussion / Re: Limit switch config help please.

« on: August 18, 2019, 04:56:49 PM »

Hi,

o am I correct in assuming that X +++ and X--- can be wired in series and use the same input pin on the C10 ?? (Same for y & Z of course) but then again if all 5 switched are wired in series and are set normally closed, then any one of the switches being triggered will cause a stop ??

Yes, that is correct. In the early days of Mach when everyone used a parallel port with so few inputs it was the norm to connect limit switches
in series. You could also nominate three of the limits, one for each axis as home switches. The problem becomes that Mach has to interpret what any
given switch event means, was it intended as a home event or is it a limit for which an immediate Estop is in order?.

With an ESS and two breakout boards you have plenty of inputs and do not have to compromise. You have sufficient inputs to have three separate inputs
for three individual home switches and six inputs for six limit switches. This would mean for instance you can use proximity switches as limits and not
have to try to wire them in series/parallel on some other tricky combination and still have microswitches for home switches. No tricky interpretation by Mach
required.

Home switches can be anywhere on an axis, even in the middle. It is normal to place them at one end of each axis however but they don't have to be right at the
absolute end. My home switches are within 3mm short of each axis end with limit switches just beyond them.

You might ask 'what is the sense of having machine 0,0,0 somewhere inside the travel envelope', but that is what 'home offsets are all about.
Thus if your X axis home switch is 10mm from the negative limit then you would nominate the X axis home offset as 10mm. Thus when the
X axis homed its machine coordinate would not be set to zero but rather to 10mm. When the X axis is homed it is 10mm away from the negative
limit and with the home offset, hey presto, the machine coordinate is 10mm as well.

Craig

2104

Mach4 General Discussion / Re: Limit switch config help please.

« on: August 18, 2019, 02:40:51 PM »

Hi,
I personally find roller plunger snap action microswitches to be preferable for home switches.

https://nz.element14.com/honeywell/bzc-2rq18-a2/switch-basic-top-roller-plunger/dp/1525198

Proximity sensors make good limit switches. I recommend Zener diodes as MN300 proposed.......you risk
over-voltaging your C10s input TTL ICs without them. Note also that you cant really wire them in series, with
a proximity switch you are pretty much required to have one input per switch. Microswitches, when used as
limits can be wired in series.

Craig

2105

Mach4 General Discussion / Re: Limit switch config help please.

« on: August 18, 2019, 06:58:27 AM »

Hi,

Can I use the same switch for home and Limit for each of my axis or do I really need separate switches

Yes you can but I always recommend separate home and limit switches.

do I really need X+ and X- limit switches.

If you are going to have limit switches then yes....you need two switches per axis, one at the positive limit and another at the negative
limit. You could use 'soft limits' instead of limit switches. Genuine limit switches are safer but if you have good home switches
and homing procedures then soft limits are a reasonable proposition. If you  don't have good home switches and homing
procedures then you better have limits or you will crash badly and repeatedly.

Craig

2106

PoKeys / Re: Pokeys57CNC and homing to middle ?

« on: August 17, 2019, 02:29:17 AM »

Hi,
Machs program structure and it API is a major part of 'coding in Lua'. In fact Lua is pretty simple, even if it has
a syntax 'only a mother could love' but the structure and API really make Mach4 so versatile.

I do have a solution for you....its a bit long winded but it works. Remember this workaround is because you cant be bothered
to shift your home switches.......so no complaining that its difficult!

Firstly you cannot set the machine coordinates in Mach at will. You can't do this in Mach3 OR Mach4.
I have a cheat that allows you to do so in Mach4.....it was an interesting excerise but in truth I never use it.

The only way you can 'set' the machine coordinates is by homing, also called referencing, your machine. Thereafter the
machine coordinates are 0,0,0 or some other set of numbers that you programmatically define as 'home offsets'

Lets assume that you are in  Mach4 session and you have by whatever means referenced your machine so your machine
coordinates are valid relative to the nominal home positions determined by your home switches. When you shut Mach4 down
you could save the current machine e coordinates is the .ini file. Once the machine is shut down it seems highly likely that
your machine wont move until you start a new session.

When you start a new session initially Mach has no idea where it is, it has lost all reference to the previous session. What Mach
may reasonably guess is the the machine is in the same position as when it was shut down last. You can read the
stored machine coordinates and using those coorinates guess whether the home switches are to the right or the left
of the machines current position. You can use the API I posted to set the homing direction based on Machs guess.

With Mach having set the homing direction then <Ref All> should cause the machine to move, in homing order,
towards your home switches irrespective of where the machine position is.

Should it transpire that your machine axes can or have been moved between sessions this method would fail.

Craig

2107

General Mach Discussion / Re: Mach3 RnR motion card - problem with plasma relay

« on: August 17, 2019, 02:03:16 AM »

Hi,

The only problem i have is the output signals. I cant make them work

That is the exact same problem by all the others who have posted.

My advice remains unchanged....search the forum until you find a user who has got it to work and find out how
they did it OR get a good motion controller.

Good luck.

Craig

2108

PoKeys / Re: Pokeys57CNC and homing to middle ?

« on: August 17, 2019, 01:33:13 AM »

Hi,

So currently there is no option to directly address this.

There are in fact provisions that you could use:

LUA Syntax:
dir, rc = mc.mcAxisGetHomeDir(
                              number mInst,
                              number axisId)

Description:
Get the hominig direction for the specified axis.

And this API:

LUA Syntax:
rc = mc.mcAxisSetHomeDir(
      number mInst,
      number axisId,
      number dir)

Description:
Set the specified axis' homing direction.

You can use these APIs to read and set the homing direction, all that is required is some skillful coding.
What they can't do is tell Mach on which side of the home switch it is UNTIL it has homed OR if you tell it so.
Machs great, it has a great deal of programming power to make it very flexible but its not magic.

If you do not wish to be required to tell Mach where its newly powered up state is EITHER shift your home switches
OR buy some 'you beaut' non volatile multi-turn encoder equipped servos......at considerable expense.

Craig

2109

Promote and discuss your product / Re: Dual Motor Syncing and Z-Pulse qualification of limit

« on: August 16, 2019, 11:05:21 PM »

Hi,
Mach4 and most of the Mach4 ready motion controllers support 'index homing'. Including the Hicon as previously
mentioned, the Ethernet SmoothStepper and 57CNC. I suspect the UC300 and PMDX devices support it also but
cannot definitively say so.

An axis is homed to a home switch as per normal but then the servo/stepper will drive in a preset (programmable)
direction until it detects an Index signal. This allows for homing accuracy well in advance of a normal home switch.

Additionally Mach4 allows you to programmatically link and unlink slave motors from an axis. Thus you could, with some
ingenuity and Lua coding write homing routines to exactly synchronize a gantry.

Craig

2110

PoKeys / Re: Pokeys57CNC and homing to middle ?

« on: August 16, 2019, 08:54:04 PM »

Hi,
home switches can be anywhere on an axis. When the home switch is activated it will reset the machine coordinates,
but you can choose to reset them to zero OR some offset. Thus if you had a home switch in the middle of an axis you
could set a 'home offset' equal to half the axis travel. This would result in the machine coordinate zero being at  the
end of the axis despite the home switch being in the middle.

You have identified one problem however. If for instance you set the initial homing direction to the right, and when at power up
the machine was already to the right of the home switch, the machine will travel yet further to the right hitting the end of
the axis before any home switch activation.

I solved this problem by having my home switches near (within a few millimeters) of the end of travel. Further I used
roller plunger microswitches which because of their defined and repeatable hysteresis make good home switches.
I used to have limit switches beyond the home switches but they were cheap switches and I didn't design the mounting
well and I wiped a couple out.  I removed them all and rely on 'soft limits'. Because I get very reliable and accurate homing
this has proved adequate. If I were to fit limit switches I would use inductive proximity switches. They can easily be arranged
such that an over travel event does not destroy them.

The 57CNC gives you plenty of inputs. I would take advantage of that an use one input per switch and would further recommend
separate home and limit switches. For a three axis machine that would mean six limit switches and three home switches for a total
of nine inputs. Many people combine limit and home functions but with such a capable controller you don't have to.
It means also that if a switch event occurs than Mach knows exactly what event it represents, not having to deduce whether
its a limit or a home event or even if its a X++ or an X-- event.....with one switch/one input no deduction or interpretation
is required or potential mistake be made.

Craig

https://nz.element14.com/honeywell/bzc-2rq18-a2/switch-basic-top-roller-plunger/dp/1525198
Note this is the New Zealand site and is in NZD. If you search for Element14, or equivalently for Newark in the US or
Premier Farnell in the UK you will get the same product but in your local currency.