CNC Sewing machine question

I don't think that the problem is related to having both PID and Stepper. If the system says that there is no UART for the DAC then I would expect that the problem is exactly that.
It is possible that the GM hardware or fimrware does not support having both analogue output and stepgen, but I would be rather surprised.

At last i was able to rotate motor with dac. Unfrtunately i have 2 issues:

1) Can i run 2 motors with dac, synchronously(exact timing), one motor for turning needle and the other motor is for turning the bobbin, since needle penetrates into to bobbin hole hundreds of times in a minute i need exact timing not to hit and break needle?

2) I can use needle and bobbin motors as third and fourth axis. However after thread break the machine needs to go back and all the motors rotates back, and this is expected. I wonder if there is a way to make third and fourth axis motors not to rotate back but decrease their coordinate value?

I hope the questions are clear.

You should be able to slave one motor to the other, then only drive one of them.
ie, the position command of one motor is connected to the position feedback of the other, possibly with scaling and phase offset.

Look at the recent "hexagonal boring" post on the forum for an example of the power of that.

We are preparing the setup for master slave running. However i was not able to find hexagonal boring post.
Thanks.

ahmetbm wrote: We are preparing the setup for master slave running. However i was not able to find hexagonal boring post.
Thanks.

Try this:- forum.linuxcnc.org/10-advanced-configura...-boring-linuxcnc-fun

Wow! That's interesting. I have never considered this option before. I wonder if it is possible to do with an overlocker? I do small DIY projects, such as drapers or cushions, even Halloween costumes, and soft toys. My friends also ask me to make something for them from time to time. Now, my friends brought their friends to me, and I started to receive money for the items I make. So, I decided to expand a little bit and also bought an overlocker sewing machine as an addition to my regular sewing machine after I’ve read this info sewingmachinebuffs.com/7-differences-bet...nd-overlock-machine/ . Now, I complete my projects way faster. I think that adding Linux apps will also expand my opportunities, and I can try to do something more complicated.