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Hi everyone,I’ve been working on a CNC project for a while and I’d like some advice before committing to hardware. Here’s my situation:

• I originally built a 3-axis CNC router running on GRBL (ESP32) + a custom PCB. I used that setup for a long time and gained good experience with it.
• Later, I decided to upgrade to 5-axis by adding A and C axes to the same GRBL-based system. While it functions, I quickly discovered a limitation: ESP32 GRBL doesn’t support TCP, so the machine can’t act as a proper 5-axis system.
• Because of this, I started looking into LinuxCNC. At first I wanted to use my Raspberry Pi 5, but I read that the Pi version of LinuxCNC can’t really handle full 5-axis control.
• I then tried installing LinuxCNC on an old laptop, but since it has no parallel port, I searched for hardware solutions that use Ethernet. That’s how I found Mesa boards.

From what I’ve gathered so far:

• The 7i76 series supports 5 axes and spindle control, but its encoder inputs are only for the spindle, not for axes.
• The 7i95 series seems more suitable because it supports encoder inputs for the axes as well. My thinking was that even though steppers usually work fine, it would be good to have encoder feedback to check for missed steps.

Where I’m at now:

• When testing LinuxCNC setup, I couldn’t find any 7i95 options in PNCconf, which left me confused.
• My current hardware: 2.2 Nm NEMA 23 steppers with DM556 drivers on all axes (6 motors total, since Y has dual rails).
• I don’t have encoders yet, I was waiting to see which types are actually supported by the mesa boards.
• As another option, I do have a couple of 400 W Delta B3 servos, but not enough to equip all axes. I’ve considered using them if steppers turn out too weak, but that would mean buying more servos.
• My main goal with encoders is simply to check for missed steps on the steppers.

My questions to the community:

1. Am I on the right track with the 7i95 + LinuxCNC setup for a 5-axis machine with encoder feedback?
2. Would you recommend a different Mesa board or configuration for this?
3. Are there any guides/resources for setting up a 4+ axis machine with Mesa boards and LinuxCNC?

Thanks in advance for any advice!Ozan T.

After reading Note under the table, you can set "sync0Shift=700000" in ethercat.xml
 

It's from the ethercat manual, I put a link there a post ago.
This is unique for this servo
 

You have a 1 ms cycle time in axis.ini. According to the manual you have it set to 2 ms. Change that withand check the value again with ethercat upload.
The error comes from the drive, it thinks the config is wrong.
The only thing to do is to follow the manual.
One thing I can think of is that it doesn't like variable PDOS.
But there aren't any complains about that.
You can as a next step test to define the receive and transmit PDOS
as on page 9 and 10. Include all pdo entries even the ones you don't use.
 

You should apt remove r8168 driver or it will take that one.
Best to check though, I might not remember this right.

We should probably add that Wiki page to the main docs.

Sadly I have no solutions for the problem when the gamepad disconnects. I used to use a hard-wired one and the same problem existed.
It might be possible to fix it in the driver, but doing that isn't on my personal list of "must fix" items.

However, feel free to raise an issue so we don't forget about it.
github.com/LinuxCNC/linuxcnc/issues

We should probably add that Wiki page to the main docs.

Sadly I have no solutions for the problem when the gamepad disconnects. I used to use a hard-wired one and the same problem existed.
It might be possible to fix it in the driver, but doing that isn't on my personal list of "must fix" items.

However, feel free to raise an issue so we don't forget about it.
github.com/LinuxCNC/linuxcnc/issues

Here's the old interface to the d15 connector.
J3 goes to torch- which is the bottom right of the other pic.

4 on the bottom right of the break out is 1:10 divided arc.
5 on bottom right of break out is 1:25.
They were never wired up.

There is a wire between the torch- and the old thc's interface. I think the interface has resistors and they sampled the work+ side at the thc. But i'm guessing and there's no useful documentation for it. There is a spot on the old interface for divided arc volts, but it was never hooked up. 

So I have to do at least a little wiring inside either way, so I was thinking may as well put the thcad inside the plasma while I'm at it. 
It's a high frequency machine so maybe that'll help with emi.



 

No I did not see the wiki page.

However, I played around a bit more and got a very basic setup that actually allows me to use the joysticks on the joypad to move the axis.
Switching the jog speed looks quite useful though, I'll try to adapt it. And also the dead-man switch is probably a good idea.

This is what I currently have:

 

The ARC OK and Torch ON are there, but there is voltage out at all, and that is a must for THC to function.
Might need to wire stuff inside the plasma, do you have anyone that can do that?

Yes.
Or any other combination, except tandem joints can not be on the same pin, so you can have XYZ on 1 pin and the Y2 on the 2 pin.
Check point 2 for you situation.

I am trying to figure out how to interface a thcad2 and mesa 7i97t with a hypertherm hsd130.
Originally, this machine was hooked up to an external hypertherm thc.
The hsd130 has an internal 37 pin connector that goes to a "phc interface" that has am external 15 pin connector that connected to the old thc.
Unfortunately, the phc interface's manual doesn't explain what the pins on the 15 pin connector are for or how they should be wired and the hsd130 manual doesn't even mention it.
The manual does have all the information for the internal 37 pin connector. 

 Should I just remove the phc 15 pin connector and use the 37 pin? That seems easier than trying to reverse engineer the "phc interface"?

I will try to attach the relevant pages from the manual.

The example circuits are above my head.
Do I need any relays for the arc ok and start i/o's or can they connected directly to the 7i97t?
Should I use 24v from my controllers power supply?
Can I use 2 or 3 1mohm resisters connected directly to the torch/work leads for the thcad2?

You should be careful what you wish for, I'm known for breaking software and finding bugs in these parts It's kind of how I got my start into the LinuxCNC project.  Phill probably still has nightmares haha but maybe I made up for it in the later years. 

Feedback:

1.  I'm not keen on the idea of uploading my dxf files to a random website (no offense intended).  Probably has to do with my line of work for my day job, but even still I can imagine there would be customers that would be upset about that if they consider their work proprietary or NDA, etc. (dead horse beat).  That said, I can see the convenience aspect as well.  Nothing to install, just internet connection.  I still prefer local software.  Don't worry I have plenty of benign dxfs to upload.  

2.  There are two types of countries:  Those who use the metric system, and those who have been to the moon (I know, I know, you guys are right, the metric system is easier, but I still prefer the dinosaur units over here).  So the attached dxf file is one that I exported in imperial units.  I am not sure what your software made of it, but it doesn't seem right since the size in the bottom says 46.59mm x 9.37mm.  I'm fairly certain it's 46.69in x 9.37in.  Seems like you have at least some plan to handle units as the lead in/out section says "units".

3.  The zoom is a bit wonky.  The movement is very small with my mouse wheel.  It "feels" like when you get zoomed too far in in CAD and the mouse wheel is less effective.

4.  In the Prepare section, the "Apply" buttons are a little confusing to me.  It seems intended to just click the top most apply, but the other ones (except detect chains) seem to do nothing, and then 3 of them are greyed out? 

5.  In Program, it wasn't immediately apparent to me where I go to add a tool.  Of course these are all in the metric system, but I accepted the defaults to have a play.  The kerf was hilariously large so I went back and made it smaller, but it still seemed ... off.  

6.  In tools, I am not sure a rapid speed is necessary.  Normally these would just be G0 which dont require a speed since it's driven by the machine's settings.  

7.  It's nice that I can add an operation by part.  But it would also be nice to have a "select all" option.

8.  I am not sure what "fit" does next to the lead in/out length?  The default was 5 units which is hilariously large, and checking or unchecking "fit" seems to have no effect.  That said, when I change it to something reasonable (.25), then fit does seem to keep the arc length within the kerf width...

 

9.  It seems to have put the leadin on the wrong side for some of the parts (the ones with an inner "circle").

 

10.  You can also see from the pictures above that it choked on the splines around the outside of the part.  When I simulated this, it moved at an incredible speed around these sections (again I attached the file so you could have a play).  

11.  I am a bit unsure between the Kerf Compensation of Outside, Inside, and Part.  This doesn't seem to be strictly necessary?  Wouldn't the kerf always be toward the scrap (or away from the part)?

12. When I clicked export it says "No paths available. Please create operations first.", but it just let me simulate it?

13. Some maybe helpful notes about cutter compensation: linuxcnc.org/docs/devel/html/plasma/qtpl...:cutter-compensation

I am not sure when you'd actually want to use cutter comp, I've always just relied on the CAM to offset the paths for me, and therefore it renders cutter comp unnecessary.

I think that's enough for one my first go at it haha. Hopefully that doesn't feel like I'm beating you up. Seems like you are working toward a good thing.

I am unsure what all of your goals are for the project, but if you need inspiration, SheetCAM is a pretty good software to try and emulate. I cant think of much I would want to do that it does not. It's nice to have free options for sure!








 

running your script gives:

enp1s0 r8168
enp1 r8168

I've also tried lspci -nnk | grep -iA3 net. For both ethernet ports this gives

kernel driver in use: r8168
kernel modules: r8168

I did specify DKMS in installing the package, but after this everything became plain "r8168" (????)

Are you sure you are using the DKMS driver?

Can you run this script to verify the driver name:

 

download

chmod +x edrivers.txt
 
./edrivers.txt