@jay_s_uk Thanks for your input, yes those are the two options I am deciding between.

@jay_s_uk said in Upgrading CNC to Duet 3, keep or replace existing motor drivers?:

Cons going against you here is you may need some fairly significant cooling to run the built in drivers at ~5A.

I completely forgot to ask about cooling in my initial post so I am glad you mentioned this; the existing drivers are attached to a pretty substantial heatsink and if the Duet would also need extra cooling it would definitely make the replacement a bigger project.

It sounds like the 6XD is the way to go then if there are no big advantages to the drivers that the 6HC uses over the existing ones.

@T3P3Tony I would think that I could get at least double that speed for travel moves; as I understand it that is currently limited by the LinuxCNC controller and not by the motor drivers. I will have to check the current settings and the motor gearing though to be able to answer your other questions.

@T3P3Tony I would think that I could get at least double that speed for travel moves; as I understand it that is currently limited by the LinuxCNC controller and not by the motor drivers. I will have to check the current settings and the motor gearing though to be able to answer your other questions.

@jay_s_uk Currently the max speed is ~150ipm.

@droftarts Of all of those the tighter integration was the main advantage I was thinking of. I'm far from an expert on stepper motor controllers, so would you be able to elaborate on the practical benefits of e.g. spreadCycle or any of the other additions that you mentioned?

@jay_s_uk Thanks for your input, yes those are the two options I am deciding between.

@jay_s_uk said in Upgrading CNC to Duet 3, keep or replace existing motor drivers?:

Cons going against you here is you may need some fairly significant cooling to run the built in drivers at ~5A.

I completely forgot to ask about cooling in my initial post so I am glad you mentioned this; the existing drivers are attached to a pretty substantial heatsink and if the Duet would also need extra cooling it would definitely make the replacement a bigger project.

It sounds like the 6XD is the way to go then if there are no big advantages to the drivers that the 6HC uses over the existing ones.

Hi All,

I am planning on upgrading a CNC router table to use a Duet 3, but I'm looking for some advice on whether to use the existing motor drivers or go with the built-in drivers on the Duet 3 6HC.

The router currently runs on LinuxCNC through a parallel port, and has one Gecko G201 motor driver and two drivers that look like they are either rebranded or imitation Gecko G201s. These are connected to a 40V supply. The X and Y axes both use Nema 34 5A motors and the Z axis is a Nema 23 (I didn't check the current rating on that one). I'm looking to make the upgrade as simple as possible, but I'd also like to get the most possible performance out of the machine, and so if the built-in drivers on the Duet 3 would provide me with that then I would rather use those. As far as I can tell the main advantage of the existing drivers is that they could run higher voltages (up to 80V), but since they aren't it seems to me that they would just be adding unnecessary complication in this scenario.

BTW the machine does currently run, and I have made some parts with it. The main reasons I'd like to switch to the duet are that I believe that the current setup is limiting my speed and I am also much more familiar with configuring the Duet firmware as I run them on both of my 3D printers and I have always been happy with the quality and features.

Thanks in advance for any input!