Which Duet controller for Tevo Little Monster delta printer?

martinv

Hi there,

I am the new lucky owner of two Tevo Little Monster delta printers. One of them is working fine, the other one is dead. I haven't actually tried it but the previous owner said the controller is dead. So I'm thinking about replacing the faulty controller, perhaps with a Duet. I'm quite tempted to try and improve the quality above that produced by the standard Little Monster that I have.

Looking around on the Net I'm tempted to buy a Duet 2 WiFi controller. I am wondering if this is still the best model to buy in 2023 as many posts I have read are getting quite old now. So that's really it - still buy the Duet 2, or a different (newer?) model? Any thoughts appreciated.

-Martin

dc42

@martinv the Duet 3 Mini would be a better choice provided that the stepper motors in your machine don't need more than about 1.6A peak current. Do you know what model stepper motors it uses, or what current they are normally set to in that machine?

My Kossel XL uses a Duet 3 Mini.

martinv

@dc42 Thanks for the reply. The Stepper Motors have the following written on them:

RB STEP MOTOR
42SHDC6022Z-26B
LOT NO. 190119

I have been unable to find a good match with a reliable source on the net. I have measured the face plate at 42mm (square), 47mm long. Shaft is 5mm x 24mm long. Coil resistance measures 1.7Ohms. They are very likely 1.8 degree steps on this printer based on what I've read.

I did find a Reddit comment (how much weight to give that I don't know LOL) that claimed:

42SHDC6022Z-26B
Current / Phase: 1.5 A
Rated Voltage: 3.0V DC

After all that as well as looking on Digikey and getting a bit overwhelmed I went and had a look at the contents on the microSD on the present controller. The config file has the following:

# Smoothieboard configuration file, see http://smoothieware.org/configuring-smoothie
# NOTE Lines must not exceed 132 characters, and '#' characters mean what follows is ignored
## Robot module configurations : general handling of movement G-codes and slicing into moves
...
alpha_current 1.5 # X stepper motor current
...
beta_current 1.5 # Y stepper motor current
...
gamma_current 1.5 # Z stepper motor current
...
delta_current 1.3 # First extruder stepper motor current

So is that the max current, 1.5A?

For this particular printer what would the Duet 3 Mini have that would be beneficial compared with the Duet 2?

Thanks for your help!

jay_s_uk

@martinv yes, those will work fine on a duet 3 mini.
The duet 3 mini has a couple of advantages over the duet 2

The duet 2 only has 512kb flash and this is pretty much maxed out so there may be new firmware features that don't make it to the duet 2. The duet 3 has 1024kb of flash
the duet 3 mini has CAN-FD support to its easier to expand

martinv

@jay_s_uk Thanks for the info and @dc42 too. I have just ordered a Duet 3 Mini 5+ Wifi. Exciting!