Messages

1801

Mach4 General Discussion / Re: Cycle G83 in the Lathe version creates a collision

« on: January 09, 2020, 12:55:44 AM »

Hi,

however if you tell me that it is compatible with Mach4, it must be perfectly! because the money we paid was valid.

That is rather the point, they claim to have a working Mach4 solution, and it must be said its not bad but it is far from
perfect. I doubt in fact if there is ANY controller that could be deemed perfect however there are a number that do a
better job the CSMIO. This is a great pity because CSLabs had a very VERY good reputation for quality, functionality
and support. The quality remains but the functionality lags behind others and support sucks. They also demand quite
a premium for their product....could you be satisfied?.

now I want to understand who is responsible for the G76 and G84.
the plugin or Mach4?

I cannot answer that, as in a lot of realtime ops, drill cycles included, it is a co-operative venture between the motion controller
and Mach4. It may be that there is fault on both sides. The fact that RT concludes as you do but with a different motion controller
suggests that Mach4 is at fault.

Perhaps someone from NFS would like to explain, at least in general terms, whats going on.

Craig

1802

General Mach Discussion / Re: Switching from Mach3 to Mach4

« on: January 08, 2020, 10:46:20 PM »

Hi,
NFS have no say in whom or how hardware is made for Mach3 or to  a certain extent Mach4.

In order to make a Mach4 plugin, be it for a motion controller or pendant or PLC etc, a person/organisation/company
would do well to sign a N(on) D(isclosure) A(greement) with NFS and then they get all the inside information
to make a good job. NFS is very keen to see other manufacturers making hardware and plugins for Mach4 and offer
considerable support to those who do.

At the current time the only manfacturers who have invested considerable time and effort to make a working Mach4
plugin are European ans US based. All have long experience in the Mach3 market and all have a great reputation
for support, none could really be considered cheap.

There is but one Chinese manufacturer who has made a Mach4 plugin but its that buggy that no-one uses it.
The company concerned don't seem to care either, if they've got your money you are out of luck.

As you know development of Mach3 ceased six years ago....so Mach3 is what it is....there will be no updates or increased functionality.
On the other hand Mach4 development proceeds apace.

Presumably if you are happy enough with the functionality of Mach3 then you aren't interested in mcSurface plugin, script based THC,Trace module,
Mach4 Ethercat and so on, and these are only the last few months.

Craig

1803

Mach4 General Discussion / Re: Cycle G83 in the Lathe version creates a collision

« on: January 08, 2020, 04:53:31 PM »

Hi,
CSLabs have not been very proactive in correcting their Mach4 plugin for their controller.

CSLabs are trying to promote their own software and have largely ignored Mach4. It has taken over a year for a plugin update
and it still doesn't address all the bugs. For 600 Euro I think that's pretty poor, in fact that sounds like a Chinese rip-off to me.

Craig

1804

Mach4 General Discussion / Re: Cycle G83 in the Lathe version creates a collision

« on: January 08, 2020, 04:18:13 PM »

Hi,

the only thing I know is that after spending about 1400 euros between only controller and license I expected much more.

You bought an expensive controller without doing your homework, CSLabs support for Mach4 and their customers has taken a dive.

Craig

1805

Mach4 Plugins / Re: Galil plugin compatibility

« on: January 08, 2020, 05:05:36 AM »

Hi,

I already have 1 micron linear scales fitted to my machine, so it makes sense to use them.

Agreed. As far as I am aware there are two choices to proceed, a feedback controller or load sensing servos.

If it were my choice and I chose a feedback controller I'd go with Galil, I know its expensive but you can bet it would work.
The other two would 'probably work'....but do you want to spend that sort of money on a 'probably'?, I wouldn't.
I think the CSMIO Mach4 plugin is dodgy and CSLabs don't seem to care. I hate it when Chinese companies do that
rubbish.....so why should I spare a Polish company? That leaves the Hicon, I'd want to do a deal more research
before I spent $1200USD.  Given that you've already got AC servos it seems to me like a backward step to use
them as analogue servos and use the Hicon to close the loop.

May I suggest do a bit of research on the Delta A2 series servos.

The company I bought mine from email me with offers. The latest email (deleted alas) explained that due to the volume of sales
that Delta was going to increase their discount and the company wanted to pass some of those savings on. It looked
roughly that I would save about $80USD on a 750W B2 series like I've already got OR I could have 750W A2 series
for the same as I paid for B2 series as short as a few months ago. That would put an A2 series servo/drive/cables about
$430USD excluding shipping.

http://www.ebaystores.com/fasttobuy2012

I have scanned through their listings and don't see any that match the offer they emailed me with....I would be emailing them
to get details. Just as a note Delta have a range of models that have either CANOpen OR Ethercat or some other network
combination. The network capable drives are approx. another $100USD or so. You require just the standard step/direction
units which are cheaper. That is the ASDA-A2-L drives.

https://www.deltaww.com/Products/CategoryListT1.aspx?CID=060201&PID=23&hl=en-US&Name=ASDA-A2+Series
https://www.deltaww.com/services/DownloadCenter2.aspx?secID=8&pid=2&tid=0&CID=06&itemID=060201&typeID=1&downloadID=A2+Series&title=A2+Series&dataType=3;&check=1&hl=en-US

If, after reading the user manual for the A2's, and you think it may work, would you consider buying one servo and drive to see if
you can make it work to your satisfaction?

Craig

1806

General Mach Discussion / Re: Switching from Mach3 to Mach4

« on: January 07, 2020, 05:13:32 PM »

Hi Chris,

but.. presumably there is a "transfer settings" style transition from mach3 to mach4, requiring no further setup, and also presumably if you are using a "standard" monitor 1080p the default screens will fit?

No, not really. There is a spreadsheet that will help the transition but Mach4 IS A DIFFERENT program and much of what know about Mach3 will have to
be unlearnt so you can get yourself going with Mach4.

Mach3 screens DO NOT work in Mach4. If you download Mach4 you will see the standard screens it ships with. Are those adequate?
Editing screens and/or composing new screens is very much easier in Mach4 than Mach3, having said that composing a new screen from scratch is time
consuming, if have have a real need then fine but otherwise editing or tweaking a standard screen set is the way to go. Mach4 screens display equally
well in many resolutions as befits a more modern program.

I'm not at all sure that the toolpath display in Mach4 is up to five axis stuff, there is some details on four axis display. Whether the toolpath display is
useful or believable should have no bearing whatever on the speed of the motion however.

My experience is that Mach4 toolpath following/zooming/rotation does not cause Mach to pause or otherwise 'bobble' as used to be the case with Mach3.

Craig

1807

Mach4 Plugins / Re: Galil plugin compatibility

« on: January 07, 2020, 03:53:34 PM »

Hi,

Backlash and lost motion are NOT consistent and repeatable, they are dependant on load and stiction. Linear scales compensate for this.

I agree 100%, if you are chasing the last micron then linear position sensing is required.

My contention is that with top quality ballscrews, rails/cars and a rigid bed/frame that micron level accuracy is obtainable, if not sub micron
without the complication of including a linear scale in the position loop. Having said that the latest generation of AC servos with load sensing
in addition to the regular rotary encoder have made including a linear scale within the position loop a very much easier and cheaper proposition
than it has been.

As you are probably aware the semiconductor industry have a great demand for ultra precision stages, they chase nanometers. They use interferometric
methods, an ultra precision version of more common linear scales. The position loop is closed by the servodrive and the servodrive itself handles its
own motion control as part of a distributed motion control system. A semiconductor production line could have tens if not hundreds of such stages, a
centralized feedback motion controller is totally impractical for such a large system.

Servo manufacturers are busy making network capable (Ethercat, Profibus, CANOpen etc) servodrives which are smart enough the conduct their own motion
control and closed loop control of the servo including load sensing.

My suggestion is to take advantage of that trend and use the hardware that is coming forward as a result RATHER than a feedback controller like Galill.

Craig

1808

Mach4 General Discussion / Re: Zeroing and extents

« on: January 06, 2020, 12:47:46 PM »

Hi,
sometimes the zoom is such that the machine boundaries are larger than the toolpath display winow.
Try re-genning the toolpath and zoom out....do the boundaries come into view.

Craig

1809

Mach4 Plugins / Re: Galil plugin compatibility

« on: January 06, 2020, 12:43:16 PM »

Hi,

I don't know why you're so wed to the idea of indirectly measuring the position when you can directly measure it. That's clearly a more accurate option.

Rubbish!!! Zero backlash, high accuracy, high stiffness results in ACCURATE linear position from angular angular input.
Why do you suppose there is a market for high quality ballscrews? OEMs would use cheaper ballscrews if they could....
but they can't.

If you want to close the loop on a linear scale....go to it!!...there is a cost effective solution if you'll 'un-wed' yourself
from the idea of a feedback motion controller.

Craig

1810

Mach4 Plugins / Re: Galil plugin compatibility

« on: January 06, 2020, 06:55:21 AM »

Hi,

You can go to ever finer resolution on the drive system, but it won't help with reducing the lost motion in the ball screws, leadscrew thrust bearings and in the stretching and compressing of the leadscrew

The measured and published stiffness of my ballscrews is 1110N/um. It is for this reason that I am trying to aim for a stiffness
overall of 10um @ 1kN force.

Directly measuring the position of the table rather than indirectly doing that would certainly lead to a more accurate machine,

Without good and costly linear scales I rather think that angular position of the ballscrew is at least as accurate.

LDVT probes are available in much higher resolutions, that's what Renishaw used to use.

An LVDT's resolution is inversely proportional to its stroke, so yes sub micron resolution can be had but at strokes of mm's
at best. Longer strokes, +-50mm resolution of 10um is more realistic. My own design has a stroke of +-5mm and the best
available commercial units has resolutions quoted around 1 um. If I could achieve 2um resolution I would be well satisfied.
Resolution is probably a poor concept with an analogue device like an LVDT, resolution in fact infinite but there comes a point
where the uncertainty in measurement outstrips it accuracy.

I'm surprised that there isn't a motion controller that can take step and direction pulses from Mach4, interface linear encoders and output the required movements in step and direction pulses to the servos.

After a fashion....there is. You may have noted that feedback controllers like Gallil are getting fewer and fewer as manufacturers
fade away. This trend has been happening for twenty plus years as servo drives become ever smarter. With Ethercat,
Profibus, CANOpen and similar network strategies each servodrive becomes its own motion controller in a distributed motion
control solution. Who needs expensive feedback controllers with all the programming and tuning drama when you can buy
an off the shelf servo an drive which exceeds any feedback motion controller out there?.  Given that you have AC servos
you can only be aware how much more flexible they are compared to brushed DC servos of earlier years. Already the latest generation
servo drives, including such features as load sensing, are rendering the servos like yours and mine (Delta B2's) if not
obsolete certainly outdated. A load sensing servo and servo drive do just exactly what you want, that is take step direction
pulses from Mach4 and enclose a linear scale within its feedback loop.

Where an AC servo differs from a DC servo of years past is that an AC servo MUST have superbly accurate angular information
on the position of the armature to enact field oriented control. In absence of a rotary encoder the servo drive can only
estimate its angular position with the lost motion now corresponding to loss of certainty about angular position.
That would in turn reduce the current feedback loop bandwidth from kHz to hundreds of Hz and therefore the velocity and position
loops would be even worse affected, reducing position bandwidth to a few or perhaps tens of Hz, too low to be of any use for CNC.
A loads sensing servo must still have a direct coupled encoder to maintain its bandwidth but can also close its position
on a linear scale....is that not what you want?

Craig