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Did you download this through the pcnconfig or the browser?

On my VMC that I retrofit, Im running lcnc 2.8.0 (did so a few years back), using AXIS... ive had an intermittent problem of axis completely freezing while the machine continues to operate, but not able to use any keyboard input and having to estop and kill axis via taskmanager to restart the machine.
I would consider this hugely dangerous... anyone else have an issue like this?
Its been especially long programs where the toolpath display has had to remove previous run path highlights as it goes that have caused this issue.
Lcnc 2.8.0, mesa 7i76e, dell touchscreen, i5 something or other with 8gb ram. edit: running on linux mint 19.1
Stable for short parts very well, but running long programs has now got me a little scared.

Is this one of those times where an upgrade is warranted?
 

Hallo ich möchte gerne ein 5/2 Wege Magnetventil  an eine  Mesa 7i76e anschliessen.
Ich habe folgendes in meine Hal-Datei geschrieben:
net werkzeug-auf <=motion.tool-release
net werkzeug-auf => hm2_7i76e.0.5.output -00
Vedrahtung: TB5 Ausgang 00(Mesa TB5 pin 16)

Linuxcnc meldet  unbekannt  motion.tool-release
 wo ist mein Fehler

mfg 
Hilton

 

rodw wrote:

For such a large machine upgrading from the 7i96s would be a smart move as io is limited (but you can add extra boards). eg. Depending on your needs 7i76eu, 7i95t, 7i97t.

Ok, I was just thinking that buying it once for the complete machine would be easier and more clean instead of adding the various boards per needs. Also because time sometimes makes obsolete something and its difficult to
find later.

rodw wrote:

Note that if you do fall back to ethercat, with beckhoff, you just need to add an extra input or output module at any time as required at a cost of about $50 for another 8 ports.

In fact the initial idea of going with EtherCAT was exactly to prevent not having the possibility to add later
some functionalities. To me seems that more and more industrial stuff is going EtherCAT direction.

rodw wrote:

Don't forget LinuxCNC can handle about 8 spindles so the drill could get a free ride on another Z axis stage if you are creative.

ok thanks for that info. I will have to struggle a lot with it, I know

rodw wrote:

Does your table have downdraft zones?

What you exactly mean by "downdraft zones" ? I have not yet build the table where the workpiece will sit on.
But the gantry is already existing and here are some pictures of when I received it. brastrak.com.br/files/cnc/

For such a large machine upgrading from the 7i96s would be a smart move as io is limited (but you can add extra boards). eg. Depending on your needs 7i76eu, 7i95t, 7i97t.

Note that if you do fall back to ethercat, with beckhoff, you just need to add an extra input or output module at any time as required at a cost of about $50 for another 8 ports.

Don't forget LinuxCNC can handle about 8 spindles so the drill could get a free ride on another Z axis stage if you are creative.

Does your table have downdraft zones?

Nomenclature nitpick: Unless you've got encoders on there, those are stepper motors, not servos. And even steppers + encoders are typically referred to as "closed-loop steppers", not servos.


PSU: If you're going to use a switch-mode PSU, make sure you get a big (uF rating, voltage rating) capacitor to put on it. Motors dump energy into the PSU on deceleration, which can lead to voltage spikes and blown stepper drives and/or PSU. A toroidal/transformer based supply is often recommended instead for this reason.

This may also be useful: www.geckodrive.com/support/power-supply-basics/


Wire: You may want multi-conductor wire. If that's for the steppers, 4-conductor would be good. Running 4 separate wires to each motor seems unnecessarily obnoxious.


Missing from your list: buttons, switches, fans, terminal blocks, enclosure, mounting hardware, connectors. Specifically, you'll probably want to put your parts in a box of some kind, and at the very least an e-stop is a good idea. Generally you want that wired such that it hard-cuts power to the motors+spindle of the machine or otherwise renders it in a safe state.

Drawing out everything you'll use and the connections between them can help identify gaps- eg, making sure you have enough terminal blocks. It's shockingly easy to run out of those. Ditto for enclosure space- a little planning goes a long way there, and also getting a bigger enclosure than you think you need.


Finally: I'm not familiar with all the mesa offerings (I've got a 7i76e on my mill, IIRC), but try to think about what you might want in the future and then you can decide whether it's worth buying something with spare I/Os to support it now or accepting you may need to upgrade the card later to add things. Things you might consider:

-Coolant/air blast control
-MPG
-Spindle encoder
-Touch probe
-Toolsetter
-Hardware feed hold/single-step/pause/resume/etc. buttons
-Rotary axis

IIRC you've got a Taig, and IIRC those use ER collets or equivalent... my experience is re-zeroing tools with ER collets gets old fast. I more than once trashed a tool and/or workpiece forgetting to do so... a toolsetter IMO would be worth planning for.

If you're using one of the ethernet-connected Mesa cards, you'll want a dedicated ethernet port on your pc to access it - don't share it with a connection to your home router (if you're not using wifi). PnCconf is otherwise sufficient to get you going, although I think you'll eventually find yourself hand-modifying your config files to do custom things

One consideration for the Mesa cards: if you think you'll need more field I/O, you might as well pay a little extra and get a card with that built-in. I.e. 7i76EU instead of 7i96S

I converted a manual KBC GRIP-1340 lathe to CNC, kept the handwheels connected via encoders. I can manually machine or NC with it, It is more like a 'teaching' lathe, or tool room cnc lathe. Gives you the ability to quickly face or turn a diameter without having to write code or install a gui/cam thing to do it for you.

When i spin the handwheels, then stop, the machine stops. Encoder over-run is something you can disable. Sure you dont get feedback like a manual crank, but for the odd time doing something it doesnt matter. I put microswitches in the feed sticks and spindle fwd/rev lever, right now im using on screen dials to set the pitches and speeds, but its very similar to a manual lathe when you want it to be, and exactly a CNC lathe when it has to be.

I ended up using a 7i76E and 360ppr encoders connected with a small timing belt to 3d printed gears secured to the hand wheels inside an apron box i made from some rectangle tubing. My X ballscrew isnt in the apron it is beside the cross slide. I still have the cross slide on the lathe incase a quick taper job is required. Ill probably end up ditching it eventually for a more solid mount as its a weak point.

Anyways, the machine has made its money back and then a small fountain of cash to fund the other toys. It might not be everyones cup of tea, but it works very well.
 

I started with a parallel port for a lathe conversion, it was robust enough to do the job, but eventually went with a 7i76E for it, then a VMC i retrofit with 7i76E+7i84S, then now im doing another mill with a 7i95T, the Mesa hardware is fantastic- so good that china is now knocking it off!

Parallel port to start, then work your way through things. Lots of help here on this forum!!

If you have access to a PC with a parallel port, it's a cheap and easy way to get started in CNC using knockoff breakout boards from Amazon and some cheap stepper/driver kits. That's what I did. However, this is not a robust solution. I had many problems with port pins getting fried, for example. Getting any one of the Mesa cards (I used the 7i76E) is a bit more of an investment but the electronics are much more robust, and you get to enter the worlds of "industrial lego". At that point, you'd need LinuxCNC anyway, so might as well start there.

Also, it looks like GRBL is designed to run on an embedded board, not a PC, so if you want the lowest cost-of-entry, go LinuxCNC.

This is actually pretty easy, the 7i76e comes with 2 mpg inputs and you can have them on the 7i96 as well but you have to give up a couple of pins or a Stepgen.I can't quite remember what. If you ask PCW nicely, I'm sure he will sort out the correct solution.

Once you have that sorted, there is a good example of a MPG using parallel port pins in the docs. linuxcnc.org/docs/stable/html/examples/mpg.html

But in your case, you can ditch the axis select knob because you will use a dedicated MPG for each axis. Just implement the scale select knob... I have not thought about it but you may be able to use the one scale select for both MPGs. Using digital knobs lets you minimize the number of pins you need for the scale hence the mux4 components.

The Pi4b was marginal, sometimes requiring a slower servo thread but one guy I know says the Pi5 is flawless on real machines
I'd probably pair it with a mesa ethernet card. A Mesa 7i76eU has 5 axes, 16 outputs and 32 inputs but is extensible beyond that.
Linuxcnc supports 9 axes and 32 motors
Arduino is not useful for linuxcnc
There are several GUIs that support lathes but its always best to start with axis until you get everything functional.
Of course we are friendly!
You can mess with everything!
Check the docs as they list the GUI's available but you can write your own. Some support portrait mode.
I checked the other day, there's is over 1800 pages of docs but I always refer to the online docs.
There are no limits to motor size and it will control Ethercat and analog servo motors not just step and direction.
Linuxcnc is far more flexible than Centroid and is complete as opposed to Centroid where additional upgrades are required.
But it may require more effort from you  because there are probably more decisions you need to make becsause of LinuxCNC's flexibility

Re Youtube not sure on Lathe specific videos but I have a channel which is trying to produce tutorial type material.
This one is designed to be a general introduction describing the various pathways through Linuxcnc 

I'm currently working through a series of videos building a control panel from scratch using a parallel port (3rd one to be released tonight) with a couple more planned. Once fully functional, my plan was to replace the parallel port with other controller options. Sounds like I need to include a lathe walkthrough too!



 

mesaus has one:

mesaus.com/product/7i76eu/

 and our EU dealers have more

We should have the next build lot done in about 4 weeks

Thank you I will give that a look
 

There is one on ebay right now for $200.
www.ebay.com/itm/227441166265