Electronic Artisans ELS Article

[AjohnwParticipant @ajohnw51620]

I suspect the main problem for Linuxcnc is that it will do much more than what many people want especially when they start off. Anything on Linux tends to grow like topsy according to what some one wants as they are generally the people who do it.

The docs can be confusing too. Often written by some one who is very conversant with the software – in the past. More often now it's written by some one who feels like writing some documentation. What is always lacking and not just on Linux is user orientated doc's that explain things the easy way via examples.

The other problem that can crop up is terminology such as HAL. Easy to find out what that is just google Linux HAL just as someone would if they wanted to know what something in a mac or windows machine would do. This is what comes up.

HAL was a software subsystem for UNIX-like operating systems providing hardware abstraction. HAL is now deprecated on most Linux distributions

Completely irrelevant to a user. There are other problems with documentation of software orientated things as well. Fashion. People start using wizards and devkits. Fine if these do what some one wants but detailed docs are likely to be lacking. Fortunately there is often an answer. The web or youtube. On linuxcnc for instance I immediately found 200 videos – the popular ones. Last time I was curious I found a pretty comprehensive video on building a controller. It didn't take long to find at all.

Me and software skills. In the area I like working in I have been regarded as formidable so much so it's why I retired. Funnily enough my speciality is real time and making use of processor and other hardware. It's an area that has been largely de-skilled now and only done by a few specialists for others to use. Basically I found myself in a situation where I was getting all of the problems jobs and no fun breaks from them. After 3 solid years of that I decided to get out. There were other problems as well but I am used to putting up with those.

John

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[John Stevenson 1Participant @johnstevenson1]

John.

You have confirmed what I have been saying all along.

Not one word in your post above is relevant to a USER who wants to USE a machine.

Tormach have tweaked Linux CNC for their own machines. It boots up directly into the controller screen. Just like a Fanuc, Haas, Hurco etc, etc the user doesn't even see Linux and why does he need to.

They have written the documentation for this machine, not for Linux CNC. If fact if you look thru the operating manual you see nothing of anything written before in any of the Wiki's

[Michael GilliganParticipant @michaelgilligan61133]

Posted by John Stevenson on 25/03/2016 12:15:06:

… Tormach have tweaked Linux CNC for their own machines. It boots up directly into the controller screen. Just like a Fanuc, Haas, Hurco etc, etc the user doesn't even see Linux and why does he need to.

.

John, and John

This gladiatorial 'debate' is interesting as a Spectator Sport, but; may I just ask you both:

… Does it have any direct practical relevance to those of us who might be considering the 'Electronic Leadscrew' that was the subject of his thread ?

i.e. … Has anyone published a method by which the Tormach disk can be used by someone who is willing and able to wire-up a simple stepper motor system, but does not wish to invest in Tormach hardware, or LINUX geekery?

MichaelG.

[John Stevenson 1Participant @johnstevenson1]

Posted by Michael Gilligan on 25/03/2016 12:39:22:

John, and John

This gladiatorial 'debate' is interesting as a Spectator Sport, but; may I just ask you both:

… Does it have any direct practical relevance to those of us who might be considering the 'Electronic Leadscrew' that was the subject of his thread ?

i.e. … Has anyone published a method by which the Tormach disk can be used by someone who is willing and able to wire-up a simple stepper motor system, but does not wish to invest in Tormach hardware, or LINUX geekery?

MichaelG.

.

In answer to the first part of your question on the electric leadscrew the only relevance is that because Linux can use a multi line encoder it threads properly.

The ELS, Mach 3 and the Putnam system all use a single indexing pulse which whilst 'working' does not work well and there are pitch errors.

Look back a bit in MEW and Tony Jeffree did an article comparing both systems and found them lacking.

The second part of your question is harder as one goes hand in hand with the other. Linux CNC as it stands can thread and thread well but you have to sort all the problems out for yourself.

No one has done a simple install not using specialised cards / hardware.

Perhaps a job for Johnw as his expertise is in real time software ? It is something that I for one can't understand why it can't be done.

I have just gutted a brand new Conect CNC lathe, based on a Myford ML10 for a new controller. However this thing has a multi line encoder, can do accurate threads and used to run on a BBC computer.

If we could do it then, why not now ?

[Michael GilliganParticipant @michaelgilligan61133]

Thanks, John

I will keep 'observing' for a while.

MichaelG.

[sam sokolikParticipant @samsokolik60334]

Many many people have been using linuxcnc to thread single and multi line encoders. Are they all geeks? Or did joe blow user try it and find out it wasn't so bad? For a system that is free, flexible and works – a little bit of elbow grease is going to be required on your part. Also – the linuxcnc forum is a great place to ask questions. There are many many knowledgeable people on there to help. http://forum.linuxcnc.org/forum/

To say that the developers have not listened is a bit of a stretch. There are a few things that have been done to make setup easier.

Printer port setup wizard

http://linuxcnc.org/docs/2.7/html/config/stepconf.html

mesa hardware setup wizards (very inexpensive and popular hardware interface solutions for linuxcnc)

http://linuxcnc.org/docs/2.7/html/config/pncconf.html

Those are there to get you an initial setup.

There are also other gui's now that people have written.

http://linuxcnc.org/docs/html/ (under User Interfaces)

A lathe config for say the printer port or mesa hardware could be setup entirely with the wizards. It would be pretty hard to make a wizard to configure every possible setup with linuxcnc. Getting your fingers dirty in the configuration files of linuxcnc will really show how much you can do. (The integrated ladder logic also works very well)

The documentation has been getting better and better and linuxcnc is a constantly getting bug fixes and improvements. http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Released_2.7.X (and that is just the 2.7 release)

My emco compact 5 pc lathe is running linuxcnc with the 100 line + index encoder perfectly. (without the circuit board hack – just using linuxcnc to do the required latching of the octal chip)

http://www.cnczone.com/forums/linuxcnc-formerly-emc2-/283236-cnc.html

As far as pathpilot – it is tormachs design for their machines. It is going to be even harder to configure than linuxcnc prime. There are components that are missing that might be needed for other setups. That being said – I have seen on the forum someone setup pathpilot using the printer port instead of mesa hardware – so I am sure it is possible.

sam

(Edited to fix the links)

Edited By sam sokolik on 25/03/2016 14:04:41

[AjohnwParticipant @ajohnw51620]

Posted by Michael Gilligan on 25/03/2016 12:39:22:

Posted by John Stevenson on 25/03/2016 12:15:06:

… Tormach have tweaked Linux CNC for their own machines. It boots up directly into the controller screen. Just like a Fanuc, Haas, Hurco etc, etc the user doesn't even see Linux and why does he need to.

.

John, and John

This gladiatorial 'debate' is interesting as a Spectator Sport, but; may I just ask you both:

… Does it have any direct practical relevance to those of us who might be considering the 'Electronic Leadscrew' that was the subject of his thread ?

i.e. … Has anyone published a method by which the Tormach disk can be used by someone who is willing and able to wire-up a simple stepper motor system, but does not wish to invest in Tormach hardware, or LINUX geekery?

MichaelG.

I'm inclined to agree agree Michael. All I was trying to point out is that if some one takes a little time looking around it may well be easy to use. It's the same on all sorts of things on all systems.

On the leadscrew as it's rather interesting I did hang about on it's yahoo group for a while. Personally I didn't like some of the bells and whistles. I'd be happier with something that just replaced a gearbox. I tried to buy a used lathe from Italy that had something similar fitted but didn't win the auction. The way it was used may have coloured my opinion. Simple. Set pitch and thread count and do it. Thread count could easily be distance.

The general idea came from some one that did it with a phase lock loop – an analogue plus digital chip approach rather than software. I think details on that are in the groups file section.

A sort of background murmur I picked up was difficulty with the unit tracking spindle speed accurately. Pass really but some one was going to switch to direct speed control of the motor by using a DC one and I assume an encoder. I did handle a sample off a high end machine a while ago. Very coarse thread and a high precision nut all in aluminium. It was possible to feel that the control loop was hunting as the nut was run along the thread – just. This probably represents maybe a thou or so variation probably less on an expensive commercial unit.

I'm glad some one came along that actually uses Linuxcnc rather than bleating about it and his comments hit the nail on the head.

John

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[Another JohnSParticipant @anotherjohns]

Posted by Ajohnw on 25/03/2016 14:46:59:

I'm glad some one came along that actually uses Linuxcnc rather than bleating about it and his comments hit the nail on the head.

Are you referring to Sam, or my comment earlier in this thread, or John Stevenson, or Lester (or is it the John of ELS fame) or…

Or, are you one who doesn't bother to actually read what others have written before posting? Just asking – there's a lot to read.

 

Edited By John Alexander Stewart on 25/03/2016 15:25:12

[AjohnwParticipant @ajohnw51620]

There wont be any need for a linuxcnc user to see linux John. I see some signs of it when I boot up my desktop and needn't even see that really. It could equally well carry on and load something else. A few questions in the right place should fix that sort of thing if needed.

So 200 video's aren't of use to a user. Ok fine by me.

That a beeb has done it is a good example of why I think linuxcnc is now rather dated but it represents rather a lot of work so it makes a lot of sense to use it rather than what would mean something of a fresh start. That is going on slowly but when I see comments about huge line count encoders my software hat makes me giggle. Nothing as far as I am aware has been forthcoming which means that the people doing this sort of thing want to be rich one day or aren't having much success. Maybe they lack the abilities needed. I've no idea. I suspect something heading in a different direction will appear at some point probably just for screw cutting and feeds. I have been tempted to have a go myself at times but having stopped writing the stuff I can't see myself starting again. Plus the fact that if it had someone's OS in it I'd find it a hindrance and wouldn't be prepared to spend the time that would be needed to enable me to make use of it.

John

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[Enough!Participant @enough]

Posted by Ajohnw on 25/03/2016 14:46:59:

On the leadscrew as it's rather interesting I did hang about on it's yahoo group for a while. Personally I didn't like some of the bells and whistles. I'd be happier with something that just replaced a gearbox.

I don't really understand your comment, John. The "other bells and whistles" aren't part of the basic kit and can simply not be added leaving just the gearbox replacement. All you have to do is build the minimum stepper-motor drive to suit your particular lathe. The firmware does contain drivers for those bells and whistles but they have their own menu sections which can be ignored.

That's all I did initially and I did indeed end up with something that "just replaced the gearbox" for both power feed and screwcutting. I only occasionally do the latter but it's really nice to be able to switch the power feed from roughing to finishing speed in a couple of seconds without having to redo the gears (I don't have a selector gearbox).

If the user want to expand his horizon ever-so-slightly, the firmware includes a setting that will let you feed up to a settable and repeatable position allowing you to cut up to a shoulder without setting a mechanical stop. It's very useful but if he feels it's too much of a bell/whistle he doesn't have to use it.

The only thing I've added since is a so-called "Electronic Half-Nut" which is simply a pot with a spring return to zero and two, part-travel detents. Implementation (mechanical design) is up to the user. It isn't actually necessary (I went years without it) but it does get you away from the control box and lets you control longitudinal power feed from the lathe itself (with the added advantage of an instant fast feed position for setup purposes).

[Lester CaineParticipant @lestercaine30947]

Some of you will have seen the discussions on all of these areas over the years on other lists, and we still have not come up with those elusive working plans for the time machine to give us a few more hours a day

My Taig mill is still running the version of Mach3 I started with some years ago … must be some time because the ITX box driving it still has W2k on it! I've installed many copies over the years, and as long as one sticks with 32 bi windows new ITX boxes with no pre-W7 drivers work fine. The only problem I have is down to the closed loop controller on the Taig which will from time to time stale on a job it's just done 5 times perfectly. Nothing to do with Mach3 and I've simply had no time left over to switch hardware … which is why my own ELS kit is still only half assembled, and the LinuxCNC box is still sitting on top of the Mach3 one. When I build a new controller a get someone on the phone wanting to buy it and the old set up does a job.

When I do find time to play with stuff I always document the work … mainly for my own reference later … and using the using the PHP based content management system I've been developing for 18+ years and which currently pulls in more money than CNC sales. But my plan in addition to completing a working ELS ( Which is all the Chester 3in1 here is worthy of ) is to get a working LinuxCNC set-up to parallel the single screen Mach3 set-up I've been supplying and supporting.

To add to the useless information here, I only use Windows with the CNC kit. I've run a Linux desktop for many years and as the main desktop for coming on 10 years. Modern installations of Linux are a LOT less hassle and I can configure a Linux ITX box or full server in under an hour while a Windows box is over 24 hours of install, update, and further configuring. So TODAY I find Linux a lot less greeky then windows! But we do need a bit more work on the LinuxCNC installs, or the interfaces to ARM based motion control boards.

[AjohnwParticipant @ajohnw51620]

I did mention Linuxcnc John but not Sam. I do read but sometimes cross posts crop up. I often break off to do something mid way through replying. Depends how long it is.

On Bander's post well this was my impression when I looked around at it. I think this was when I had a Myford and no gearbox so sometimes ago and was probably comparing it with the Italian one I mentioned plus what I wanted it to do. I didn't realise that parts could be left out. Different people are likely to have different ideas on how something like this should work.

Actually I did buy some bits and pieces to have a go but time and the cost of suitable dev kit and tools ruled it out at the time so it never happened. I changed lathe as well and that does have a gearbox.

John

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[AjohnwParticipant @ajohnw51620]

Posted by Lester Caine on 25/03/2016 16:47:35:

To add to the useless information here, I only use Windows with the CNC kit. I've run a Linux desktop for many years and as the main desktop for coming on 10 years. Modern installations of Linux are a LOT less hassle and I can configure a Linux ITX box or full server in under an hour while a Windows box is over 24 hours of install, update, and further configuring. So TODAY I find Linux a lot less greeky then windows! But we do need a bit more work on the LinuxCNC installs, or the interfaces to ARM based motion control boards.

Just to continue the useless information I have used Linux for my desktop for a good while longer than that and am not at all happy dealing with what's under the hood and have no intention of ever being conversant with it, just what I may need to do which is basically compile applications on the few occasions I do need to do that. Many things install with a single click. I have messed things up a couple of times and visit the distro's forum where it's been sorted pretty quickly. At odd times I have wanted to find out what is going on somewhere on the machine and for me that needs google but doesn't take long and I forget as soon as I have done what ever I wanted to do.

I've stuck with Suse now OpenSuse which has always made installs pretty easy. I do configure what I want in that area but for many the defaults would be fine. It's only a matter of deciding on partitioning in my case plus always using a root account – admin user in other words. I've also stuck with KDE for the desktop through thick and thin. That plus a utility called YAST makes doing what I might want to do to the machine easy. If not the forum will always help. LinuxQuestions can be useful at times too. On both there are people who will take a lot of time steering people through what they might want to do.

John

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[Lester CaineParticipant @lestercaine30947]

Posted by Ajohnw on 25/03/2016 19:28:08:

I've stuck with Suse now OpenSuse which has always made installs pretty easy. I do configure what I want in that area but for many the defaults would be fine. It's only a matter of deciding on partitioning in my case plus always using a root account – admin user in other words. I've also stuck with KDE for the desktop through thick and thin. That plus a utility called YAST makes doing what I might want to do to the machine easy.

Snap … been through a number of other distros and ended up with Gnome for a time while they removed the crap added to KDE, but I'm back on SUSE and classic KDE. It would be nice if YAST was still the default admin interface, but I still have the UniPlus+ System 5 manuals on the shelf here – little of the basics have changed since 1980. Long before Gates ripped off CP/M

It is a simple fact that nowadays both Linux and Windows desktops are a complete mess which has nothing to do with the improving usability and everything to do with too many Indians trying to get their own agendas taken as the 'new way'. If we go back to the likes of W2k and earlier versions of KDE then the whole user interface would be cleaner and faster? The motion control code has nothing to do with operating systems.

[AjohnwParticipant @ajohnw51620]

To many indians wanting to do this and that has been a problem – I can remember letting out an Oh No on the kde mailing list when some bright young c++ programmer wanted to do a daemon to do all indexing. I was gob smacked by what it had indexed when I finally found why my discs kept clicking. Just about everything I had looked at even on the web so turned it off. Later I found I couldn't have my posh clock unless it was active – that never reached a release. Frankly now on 12.3, I was waiting for 12.4, there is no signs of it doing it's stuff and it only does what it needs to. I still run Kmail 3 via the PIM though. It's a problem with C++, bit like Highlander – there can only be one but maybe mail justifies it's own. Looks like I will have to update to 13.2 as not sure I want to try Leap yet but I'll bet OpenSuse has the most stable KDE5 just as they did on 4. I still use Kfind.

I thought there must be something about on linuxcnc to simplify the g code aspect so took a look, Bear in mind that this was posted some time ago

**LINK**

The forum discussion is still ongoing

**LINK**

If people read doc's and see rather strange comments about can be tabbed into something else it often means that it can be dragged and dropped – may work like that may not.

John

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[AjohnwParticipant @ajohnw51620]

Another example of a linuxcnc interface

**LINK**

I guess the real problem for some is that it's clearly highly configurable so rather than bleat like a sheep it would best to both look around and ask because some one some where will have probably done it.

There also seems to be route from freecad. FreeScad is early days but seems to be for checking the G Code before actually using it. Typical Linux work duplication.

All this from 20 min of looking at a couple of video's. – I skip through them for find the interesting bits.

John

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[John Stevenson 1Participant @johnstevenson1]

Any Pugh is a very, very, accomplished programmer. What I'd call formidable.

Now get Joe Blogs in the street to load this into Ubuntu and get it running.

Btw on the next to last page in a post from Andy it says

"These macros don't produce any G-code. Each operation runs a pre-programmed routine with different parameters.

If you want to produce G-code then look at NGCGUI or Features or JT's G-code generator"

So not sure if it works or just looks good.

Contary to popular opinion I am not bashing Linux, in fact the opposite. I want the community to see that there is a market for just users. It's hard though. In fact Andy, in another thread is genuinely curious why someone wants to use the Tormach screen over what is available.

It's down to use, familiarity and perception. Most modern controllers look very similar and for a purpose. The skill pool of users to operate this machines isn't endless and making them similar means users can swap between machines / jobs without expensive retraining.

Now when I show prospecting users these Linux CNC screens with the exception of two the rest don't even have start stop buttons and modifying a screen isn't drag and drop but requires someone with formidable programming skills.

This is fact because I believe in chequebook engineering, you get where you want to go far faster.

When my gear hobber broke down I knew it could get got up and running on Linux. In fact the Formidable Andy Pugh has done exactly what I wanted and has a you tube video on it. So a local Linux Guru was contacted, Hi Dave and he spent a few hours with a spare computer setting up and then popped down and we fitted it up.

It works well, it wasn't easy even the guru had problems but it works and all this does it run one axis and has two rev counters slapped in the middle of the screen, one for hob sped and one for work speed.

Certainly not a product you would sell on looks.

So long short is there will always be programmers and people who want to play.

There will always be users and people who want to use machines to make what they want

There will be people like Tormach, who want a package they have control over for support issues

Unfortunately these three categories cannot overlap, each wants a specific use.

[Mark P.Participant @markp]

If I wanted to fit an ELS to my lathe just for screw cutting, is there a simple programme that I could use with a laptop without using the controller as shown in the artical?
Mark .p

[Alan JacksonParticipant @alanjackson47790]

Mark

You can use TurboCNC which is a Dos program you can download, it will work from an older laptop with a printer port. It requires a spindle sensor showing one pulse per rev and a stepper motor and driver. I use it on my Stepperhead lathe and it works very well. It does not have the luxury of the more sophisticated systems mentioned on this thread but it is very suited to model engineers etc. I described it in more detail on my Stepperhead articles. Here it is on utube, you can hear a slight speed variation but this should not be of any real concern in most circumstances.

Alan

[John Stevenson 1Participant @johnstevenson1]

Mark and anyone else that is still following the practical side of this conversation instead of the theoretical "I may well do it one day "

Then Weston Bye who writes for Home shop machinist put together a stand alone ELS a while ago that is interesting to read.

 

http://bbs.homeshopmachinist.net/threads/42769-Electronic-Threading-my-method

 

Clickable link added.

Edited By John Stevenson on 26/03/2016 22:52:36

[Michael GilliganParticipant @michaelgilligan61133]

Posted by John Stevenson on 26/03/2016 22:51:57:

Mark and anyone else that is still following the practical side …

.

Thanks, John

MichaelG.

[AjohnwParticipant @ajohnw51620]

Posted by John Stevenson on 26/03/2016 22:51:57:

Mark and anyone else that is still following the practical side of this conversation instead of the theoretical "I may well do it one day "

Then Weston Bye who writes for Home shop machinist put together a stand alone ELS a while ago that is interesting to read.

**LINK**

Clickable link added.

Edited By John Stevenson on 26/03/2016 22:52:36

Dear Dear, Toys out of pram etc.

People might find the electronic method I mentioned earlier interesting.

John

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[Michael GilliganParticipant @michaelgilligan61133]

Ajohnw,

Perhaps I am missing some 'programmers joke' but I really do not understand your last outburst.

JohnS has provided a link to something that is comprehensible, and I [for one] am grateful.

The details [mechanical and electronic] may or may not prove to be directly transferable; but I like the concept.

I particularly like his starting-point:

[quote] To do this I had to start with a sufficiently large pulse count per revolution of the spindle – in the case of my equipment, 8000 pulses per spindle revolution. [/quote]

… I think that thread should prove to be genuinely educational.

MichaelG.

Edited By Michael Gilligan on 27/03/2016 08:56:49

[Mark P.Participant @markp]

Thanks for the replies I will have a look at the links and dig out the old copies of MEW.
Regards Mark P.

[AjohnwParticipant @ajohnw51620]

There is some practical information around on a different method of making an ELS. This is the basic details

What a metric implementation can do

And a rough schematic

The original article is here giving details of how the "ratios" are achieved. The gearbox is just motor speed reduction.

**LINK**

More on the yahoo group. As is often the case there doesn't seem to be much info on how well it works and it uses as servo motor to drive the lead screw – that means a low inertia motor is probably needed according to some leaving the question of how low. There is also some detail of an attempt to replace the motor with a stepper. Not enough to see how well that went but there could be other methods.

John

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