1 signal two stepper drives

[jmh474]

Iv got a leafboy77 and found out it doesn't support slave function, but my build requires 2 for my Y axis.

Akz250 runs on mach3

Would it be possible to share a single signal to run 2 x stepper drivers? If so would there be any concerns I should be aware of?

I have seen people run 2 steppers off one drive but I think 2 drives running individual steppers will be a better way to go.

Or is there away around this to slave an output?

[JAZZCNC]

What controller does it use.? If it's a parallel port then mach3 will let you use slaving. If it's USB or Ethernet then it's an external controller and that will determine if can or cannot use slaving.

Whether you can use 2 drives from one Output will depend on the current of the Output and what the drives will draw. It can be done if you have the current.

The downside, other than putting extra stress on the Output, is while it allows you to drive 2 motors they can't be controlled individually so the gantry cannot be squared using Home switches at each side.

Don't run 2 steppers from one drive. this is a very bad idea that will make the motors run very rough.

[jmh474]

It's a usb input

I can use a seprate power supply to power the drivers so I don't need to wory about current problem.

I could just square up the router after every job done, I have asked other people and they've said they've never had a problem doing it this way

[dazp1976]

It's a usb input

I can use a seprate power supply to power the drivers so I don't need to wory about current problem.

I could just square up the router after every job done, I have asked other people and they've said they've never had a problem doing it this way

Find a new controller with a mach plugin that supports slaving. It will be less hassle.
Ditch usb and get ethernet. Usb can play grief with a router vfd.

[JAZZCNC]

It's a usb input

Ok that will be why it can't Slave and this alone is sign that it's not a very good controller, expect issues along the way from other things.!

I can use a seprate power supply to power the drivers so I don't need to wory about current problem.

The current I'm talking about has nothing to do with the current required to power the drives and motors so PSU size doesn't come into it.

Without getting too deep or technical I am talking about the current Step & Dir Inputs which are going to draw from the controllers Outputs. Each Output will have a max amount of current it can supply which will be in the Milliamp range and the drives Inputs will require a certain amount of current to operate, again in the milliamp range, which they draw from the Outputs.
So, for instance, let's say your controller's Output can provide 15ma and the drive's input requires 7ma to operate so when operating a single drive there is no problem because you have plenty of spare capacity. However, controlling 2 drives then you do have a problem because each drive will pull 7ma requiring 14ma total but the output can only provide 15ma which doesn't leave any spare capacity and you could get issues from signal loss and lost steps, etc.
If the inputs pull more than the Outputs can provide then you could damage the controller and you will definitely have a signal loss at best if they work at all.

So to know if this will work for you then you first need to know the spec of the controller's Outputs and the spec of the inputs of the drive.
If not then you could easily run into trouble with crazy shit happening or blow the controllers Outputs.

Now because I'm guessing it's a cheap controller because its USB and doesn't slave and the fact the drives will probably be cheap drives to match then there is a good chance you will have the worst of both worlds where the Outputs are low current and drives inputs will require a high current. This is common of cheaper components.
In all honesty, USB is shite for CNC as it's flaky in power terms and easily affected with electrical noise, best avoided if possible.

I could just square up the router after every job done, I have asked other people and they've said they've never had a problem doing it this way

Yes you can and some people just crash the machine into hard stops to square up but why would you when a proper controller will and should square it up for you in nice controlled why without you ever having to think about it.?

[dazp1976]

Ok that will be why it can't Slave and this alone is sign that it's not a very good controller, expect issues along the way from other things.!
Without getting too deep or technical I am talking about the current Step & Dir Inputs which are going to draw from the controllers Outputs. Each Output will have a max amount of current it can supply which will be in the Milliamp range and the drives Inputs will require a certain amount of current to operate, again in the milliamp range, which they draw from the Outputs.
So, for instance, let's say your controller's Output can provide 15ma and the drive's input requires 7ma to operate so when operating a single drive there is no problem because you have plenty of spare capacity. However, controlling 2 drives then you do have a problem because each drive will pull 7ma requiring 14ma total but the output can only provide 15ma which doesn't leave any spare capacity and you could get issues from signal loss and lost steps, etc.

Looks like stepper output = 13ma. Inputs = 7ma. General purpose OC outputs = 500ma.
Not worth the bother tbf.
http://leafboy77.com/?page_id=25/

The 5 axis version of AKZ250V3 shows slave support:
https://www.aliexpress.com/item/1005...rch-mainSearch

http://leafboy77.com/?page_id=354

The EDG381 supports slave and is ethernet:
https://www.aliexpress.com/item/4000...rch-mainSearch

http://leafboy77.com/?page_id=271/

According to this the Druffel STB4100 usb supports a slave.
https://drufelcnc.com/doc/DrufelCNC_STB4100_manual.pdf
I see these on many budget routers:
https://www.aliexpress.com/item/4000...rch-mainSearch
https://www.youtube.com/watch?v=Lt6e6WI_GaE
https://www.youtube.com/watch?v=107CmKN2Md0