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how do i test this? (and fix if broken)

Is there in existence CNC machines with such axes placement. If yes how this types of machines called?
Red -> X, Green -> Y, Blue -> Z 
Pros:
Clean working area, no way covers (only on vertical wall)
Easy way covers construction (plain sheet of metal)
Possibility to put long vertical work material (if to remove table or use other type of attachment)
4 and 5 axis could be added for rotating (smaller table or chuck)

Cons:
Please share your opinion

I didnt see that either, its what i got with my last and frustraded way by using AI.
Before I did the "Thing" above I had this as .xml but that didnt work, too

I have started by doing it exactly like this : 

It could be interesting to use halscope and record pos-cmd and pos-fb around the Machine on event.
I think your analysis is right. I have a similar problem. I zero the encoder's values before starting linuxcnc.
My issue is related to stepper motors when energized, so not necessarily same for you.

 

Ok, changing the Home_Absolute_encoder=2 to =0, no change. #'d it out altogether, still no change.
What seems to be happening or at least what I can see is that when lcnc starts up it's loading the stored g54 values from linuxcnc.var as the current machine possition but then it's zeroing out the dro a few seconds later. If the machine is enabled it's actually trying to make that move to 0 rather than just the dro zeroing out.
I've no idea at this point. Maybe an actual homing routine will sort it out. At least for now I know that if I wait a few seconds before enabling the machine I won't snap any motor shafts.

What's that? Never seen that before.
Anyway that won't work with lcec_conf, it requires a file in xml format.

Easiest way, I think, is to take the output of the command "lcec_configgen" and put that
in the ethercat-conf.xml file and use that as input to lcec-conf.

Example here to show the structure and syntax of things
github.com/dbraun1981/hal-cia402/tree/main/example
Reference to lcec and lcec_conf
github.com/linuxcnc-ethercat/linuxcnc-ethercat
 

Okay, so one drive is for a spindle?
I made an adaptation to the cia402 component for the driver to work in PV (Profile velocity) mode
which is better suited to run as spindle.
Check out here github.com/MetalMusings/cia402pv
This person made it work after a while forum.linuxcnc.org/38-general-linuxcnc-q...tor-as-spindle-motor
 

Hallo zusammen , ich bin seid ca. 4 Wochen der stolze Besitzer einer Maho 500 W4 , es ist die selbe wie in dem User DoWerna jedoch haben sich bei dem Eintrag nicht alle meine fragen geklärt , zum einen wie ist das mit den Mesa karten gibt es unterschiede zwischen PCIe oder über Lan Kabel bzw. was ist besser oder besser erweiterbar oder eventuell günstiger und wie ist das mit dem Bedienpult welches ich selber bauen möchte ? ich habe mir die benötigten Taster zusammengeschrieben und möchte das auch in der Art machen mit Gmoccapy und dachte an die selbe Bedienart wie bei den Kunzmann 3/4 Maschinen dass dort also noch ein Handrad mit Achsauswahl hinzugefügt werden soll (Haidenhain Steuerung). ich bin kein Elektroniker sondern Industriemechaniker und muss mich dort in das Thema selber hineinarbeiten deswegen wäre die ein oder andere Hilfe gerade was die Mesa karten angeht nicht so schlecht  ich mache gerade einen Maschinenbautechniker und kenne mich dadurch schon ein wenig mit SPS aus aber manche Sachen kann man dort übertragen aber gerade das mit diesen Signalen bzw. von Haidenhain Glasmessstäben zu denen die die Mesa versteht ist für mich Neuland . gruß Tom

Looks like it's going to be the Home_absolute_encoder=2
I should have said that my motors don't have absolute encoders.

Ok so I've found what's happening but not why. Video below shows it in detail.
A few seconds after Lcnc loads the, I guess, current possition of the machine, the possition it starts up in lets say, is changing. I can see it jump from one position to the new one. Sometimes it's just the Z that jumps, sometimes it's the z and the y.
I hadn't noticed it before as I was so busy watching the motors. If I enable the machine before the current position in lcnc updates it tries to move to that new position. Again, easier to show it than describe it. It's pretty clear in the video, linked here

Could this be something to do with absolute encoders? The original machine that I'm using the files from had absolute encoders. Is there something saving the machine position on shutdown or something like that?


 

The reference to the forum post was helpful. I now have the basic framework up and running. The servo, which is supposed to act as a spindle, is working to the point that it can be controlled with M commands, and the stepper driver (one driver for two closed-loop steppers) is also working. I've attached the files. More to come.

de.aliexpress.com/item/1005008271228331....gatewayAdapt=glo2deu

de.aliexpress.com/item/1005010098887410....gatewayAdapt=glo2deu

 

tommylight wrote:

The link i posted, explicitly mentions making the machine work without encoder feedback to LinuxCNC first, so enable the stepgen feedback in the hal file and omit the encoder feedback, test the machine, set the scaling correctly, and only after getting this done activate the encoder feedback and omit the stepgen feedback.
Closed loop stepers when loop is closed on the drives are viewed as normal open loop steppers from LinuxCNC.
So yes, it should work with your drives, just make sure they work properly in open loop mode to LinuxCNC.

Thanks tommy,
so i will test it today.
hopefully this will work.
This was a lot of work adapting these linear-encoders and make all work, but it would be an extreme optimization of my machine to get it to the level of accuracy I always wanted. Not least to finally get a handle on the occasional step losses on the X-axis.

But with you all, i am sure. At the end this will work! ;o)

So I've got my machine to the point of wiring up and testing motors. Made adapter plates and fitted everything off temporarily.

I'm running into an issue when I hit machine enable in LCNC.
One or more motors will jump, move that is, violently for a split second.
Only for a split second and only once, a few seconds after I hit enable.
Sometimes it'll cause LCNC to error out (servo amp error?) and other times not.
The machine continues to work as if nothing's happened though, if it throws an error i just hit enable again and it's good to go.
No jump after the first startup. I can turn the machine enable button on and off as many times as I like and it's fine after the first time.
Sometimes it doesn't do it at all!
I've checked all the encoder cables and motor cables.
I've swapped all the cat5 cables connecting the drives.
I've auto tuned all the drives in ASDA soft. Any jogging or tuning functions from the drive or the drive software work flawlessly, no jump.

I'm at a bit of a loss. I assume LCNC is sending something to the drive and maybe it's position dependent? I've messed around with how I close out of LCNC looking for patterns but I can't really narrow it down.

I've uploaded a video of the Z axis jumping. It's pretty violent, like max speed and acceleration for 1/10 of a second.

Youtube Video

Hal, ini and ethercat xml are attached. I worked from someone else's files, hence the EL8 name.

PCW, thanks again for your hints! 
Maybe you remember, that I have had that latency problem posted somewhere this year and had it solved. But, I will follow your advice and go through this process agein, tomorrow. I did never do that diagnosis with HALscope but I will do this, too. 
Yes, my thoughts up to yesterday was mechanical fault but the measurements today say no. These hundreds that I found are totally acceptable for me, but the tenths not. I really don't know where these deviations come from. Maybe I check the latency again, and take a  look at Halscope, and got to all screws that fix the Z axis.
BTW _ I made measurements at the milling spindle head with a spring scale: I got 1/10 in Y direction at 10 kg, 2/10th in X direction at 10kg, so this is way under my deviations at the milled part. 

I will report my findings, thanks for your hints again!
Hanno 
 

Thanks for your reply, Lcvette!The alarm comes at the motor, Lcnc does not even react on this, because my alarm loop does not work actually. I have to find out why, in the next steps. Yes, indeed, i have ballscrews and especially on Y, a C5 with double Nut. Yes, I know that paired bearings would be better, but i cannot afford them. The bearings are from NSK,and the dealer says I have to set a spacer in between (0.5mm) to set the backlash to exactly zero. Otherwise I would have a small amount of play within. So, I hope this information was ok. I know other bearings that are paired without backlash, but they are way more expensive. I took measurements today and found just 1/100mm backlash, measured at the end of the ballscrew. I found some more hundreds, measuring at high feeds, driven by my handwheel that makes stepping the axis, not smooth running, there were some more 2-3 hundreds, measured at the side part that holds the Bearing and the motor, I think it's a resonance of the whole system at that side. Maybe additionally triggered by the belt drive. Its a HTD15 mm belt, 2:1 reduction, same as at X axis. Belt tension is strong enough, I can move it just 5-6mm from above in the middle of the belt. Well, I dont have a feedback loop back to LCNC, the motor is a JMC 3.3 Nm Nema 24 CL Stepper with its own closed loop.
So, what FF do you mean, FF1 that is set to 1.0? Because somebody else said a tiny amount of maybe 0,003 should help too.  
 
 
(photo from whole machine is not accepted althoug it is under 1 MB)

Thanks a lot for thinking about my problem! 
Ahh just seeing your next posting - what exactly does seem too big for you!