[chile]

Hi everyone, I hope this is the right section of the forum.
I have an issue with my cnc, it's a 3-axis (dual y driver/motor) closed-loop, which I won't name for correctness.
The machine is controlled by Mach3 with a legitimate license and an XHC 4 Ethernet board (already replaced with no luck).
Every now and then, in a completely random manner, during operation, the second Y-axis (A) of the machine stops while the first one continues to move, twisting the gantry until it can't move anymore, and then it goes into an error state.
After this problem occurs, resetting the drivers with an e-stop or even turning off the machine allows me to move it regularly with jog controls. However, if I give a G-code command, axis A remains still, and of course, axis Y goes into error after a short movement and this give me the opportunity to make some test (I've already done countless tests with wiring, drivers, and motors swapping etc). This time I tried connecting an oscilloscope to the outputs of the control board, and it confirms that there's no signal coming from the A-axis port. More precisely there's signal when jogging but there's no signal when sending gcode commands.
You can find a video at this link: https://youtu.be/OxL9pzbboVc
Oscilloscope probes are connected to Y and A axis

Among the tests performed with no success:

Replaced the control board
Used 2 different PCs
Tested 3 different operating systems (Windows XP, 7, 10)
Tried 3 versions of Mach (3.43.66, .60, .22)
Tested 3 versions of XHC board drivers (3.15, 3.17, 3.19)
I use the machine for work, so this problem is a big PITA, to say the least...

Does anyone have any idea on Wath can it be the problem?
Thank you in advance.

[chile]

SHORT VERSION:
The control board, without drivers connected, on the A axis (slave to Y) as output when jogging but no output signal when I send gcode command.
Control board already replaced.
Tried differ is, different mach3 versions and different control board plugin releases.

[joeavaerage]

Hi,
I have a very poor opinion of XHC products. You might try emailing XHC, many have tried and had no response.

I use an Ethernet SmoothStepper (Warp9 TD) and they work as advertised.

Secondly all development of Mach3 ceased nearly nine years ago, it still works but I think is obsolete. I've been using Mach4 for eight years
and its light years ahead.

If you use your machine for work, then a few hundred invested to bring it up to date and have it reliable is a no-brainer.

I too use my machine for work, and its become indispensable to it, so I would not say 'no expense spared' but I damned well do spend whatever I have to to make it
reliable, I just cant afford not to.

Craig

[chile]

Hi,
I have a very poor opinion of XHC products.

Well... I totally agree!

[joeavaerage]

Hi,
I rather suspect that at one time XHC had a talented engineer, or maybe a team of them. They developed the hardware and the plugin software.
At the time they were considered very good. Since then, that/those engineers have left the company and now there is little or no technical support.

This is the problem with the Chinese model of copying and pirating of intellectual property. If there is no protection of intellectual property then there is no way to
repay any development costs with the consequence that no development is done.

Ten years ago, XHC looked to have a good product and good technical support with ongoing development....but that has evaporated. Now all that is left is a company manufacturing
and selling but with little to no idea how it works.

Craig