Hardware advise....

CNCModeller

Hi All,
I'm starting to think about my mill conversion and was wondering about hardware selection.

My question is, since I'm planning on using 1HCL drivers for the main motion axes is there any reason not to just use a Duet 3 Mini 5+ as the main controller?

Any constructive thoughts would be much appreciated.

All the best
Barry M

jay_s_uk

@CNCModeller how many are you going to use? Just 2 for X and Y?

CNCModeller

@jay_s_uk said in Hardware advise....:

@CNCModeller how many are you going to use? Just 2 for X and Y?

I was probably going to get to 4 1HCLs and magnetic encoders as I wanted to go "on axes" closed loop on X, Y, Z and a rotary axis.

I was going to use more stepper drivers for a tool changer, but was hoping to control that over CAN to make it easier to maintain and remove if necessary.

Still spitballing this TBH, just thinking out loud/ exploring options.

Cheers
Barry M

jay_s_uk

@CNCModeller IIRC, it was said that a duet 3 mini should be ok with 4x1LC toolboards so I would expect it to be ok with 4x1HLCs.

o_lampe

@CNCModeller Which stepper motors do you plan to use?
I remember Duet3D introduced their own Hi-Res closed loop actuators a few month ago, but a short check on their webshop didn't show any.
Maybe it's worth testing them? Or use those low-res encoder steppers already available.

CNCModeller

@o_lampe my plan "A" is to use the existing stepper motors with the addition of optical quadrature linear scales on the linear axes and a magnetic quadrature rotary scale on the rotary axis. Plus magnetic encoders on the motors.

Once I understand maximum travel speeds with the existing motors and new control architecture I'll consider if they need upgrading.

Hoping to de-risk this on my polar printer bed with a magnetic and quadrature encoder setup before buying all of the necessary electronics for the mill.

dc42

@CNCModeller said in Hardware advise....:

I was probably going to get to 4 1HCLs and magnetic encoders as I wanted to go "on axes" closed loop on X, Y, Z and a rotary axis.
I was going to use more stepper drivers for a tool changer, but was hoping to control that over CAN to make it easier to maintain and remove if necessary.

The Duet 3 Mini should handle the 4 axes via 1HCLs without difficulty. Any additional stepper drivers for a tool changer would only be used occasionally, so they wouldn't create much extra load whether you drive them directly or over CAN.

If you definitely don't want to drive any axes from the main board then the main board 6XD is another possibility. It has the same high-performance processor and dual CAN interfaces as the 6HC but it costs less, and it doesn't have the 48V VIN option nor the optional WiFi module.