Upgrading CR-10S Steppers & PS to 24v Suggested Z replacement



  • For the fans you can run them at 12v by using a single buck converter from the 24v supply, or by using a direct 12v from your seperate 12v supply and feeding it into the V_Fan pin on the Duet, which will supply your fan block with 12v and allow you to continue to use PWM fan control.

    See here for more details: https://duet3d.dozuki.com/Wiki/Connecting_and_configuring_fans

    For the Z axis steppers you should try to work out a combination of lead screw pitch/lead and motor resolution that would leave you with an even step resolution so that you can use any layer height you want, or at least doesn't prohibit you from using a layer height you might want. So called magic layer heights. This is usually easier to obtain with a 0.9 degree motor. You can use this calculator to see if you can obtain the layer heights you want. https://www.prusaprinters.org/calculator/#optimallayer

    Your settings look reasonable.



  • I measured my Z motors on my CR-10s:
    Resistance: 9.6Ohm
    Inductance: 7.6mHy@1kHz (frequency used in datasheets)
    Since I was keeping my 12V PSU for the bed (I haven't checked if it can be wired for 24V, but it has 4 pads) I only supply 27.4V to the board and everything else is 12V powered (at 27.5-.6V the maestro doesn't let you move the steppers).
    edit: let us know how the swap works out, I would love to be able to use spreadcycle in silence.



  • 27v is really high. 25v is the limit.
    Why are you putting so much voltage through it?



  • @phaedrux Because the limit for the maestro is 28V and the factory motors are high inductance, to the point that the chopper frequency is still in the audible range even at the max voltage.



  • Fair enough. At least there's a method to your madness. ☺



  • what about z steppers with integrated lead screw?
    dont know the length you need
    https://e3d-online.com/motors-leadscrew-motor-with-pom-nut


  • administrators

    @puterpro said in Upgrading CR-10S Steppers & PS to 24v Suggested Z replacement:

    So I'm about to replace all the steppers on my CR-10S with some upgraded motors.
    I'm using three 17hs19-2004s1, but need some advice on replacing current current Z motors.
    The new X,Y, &E are: https://www.omc-stepperonline.com/nema-17-bipolar-59ncm-84ozin-2a-42x48mm-4wires-w-1m-cable-and-connector-17hs19-2004s1.html

    The rated current of those motors is a little high for the Maestro, but not impossibly high. With fan cooling of the Maestro, you can run them at 1.2A which is 60% of rated current. The 17hs19-1684s1 might have been a better choice.

    Why are you concerned about the existing Z motors - are they noisy at idle, or something else?



  • @zapta - Interesting about the dual voltage on the bed, never ran into that one, I'll have to look at it. Thx!

    @Phaedrux - You always have such helpful ideas! Fans - I forgot that Wiki entry. I'll puzzle it out, thx!
    For the Z axis, I didn't have all the numbers, so I wasn't sure of configuring the Z motors. @genghisnico13 helped me with that. I'll probably stick with the stock for now. Oh - I have the madness, not positive about the method part, mostly fake it. 😜

    @genghisnico13 - THANK YOU! I've been looking for that for months! That's good info on the voltages too. I'll look at the 24v to the bed thing later this week and report back (should be able to just ohm it out ...)
    I planned on starting at 24.5v and then inch it up, checking things, nice to have a guide. I'll be sure to post back.

    @Veti - If I end up replacing them I'll follow that up. For now I suspect the OEM's will be OK once I do a bit of tuning, thx for the link!

    @dc42 - I considered the 17hs19-1684s1, but down the road I expect to build a bigger machine so I figured running the 2004S1's detuned a bit would work, then I could steal them for the new machine.

    I'll setup the current to:
    M906 X1200 Y1200 Z700 E900 U700.00 I30
    Think that will be a safe starting point? Would detuning down to 1.1A until I get the active cooling box done help, or will that starve those beasts? (I'm using your Maestro box currently)

    Push comes to shove I can return the 2004S1 and get the 1684s1's instead (out of stock though ...)

    Thanks for the heads up on the cooling - I did a remix of a dual fan box here:
    https://www.thingiverse.com/thing:3520236

    I setup a channeled airflow on the drivers. I'm still tweaking the small airflow holes along the front and right side. Take a peek and let me know what you think ... Thx!

    Existing steppers - didn't have the resistance & inductance values (do now), was concerned about the config for them at the higher voltage. I'll have to see how they behave with the 24v supply.

    Thanks, as always.



  • @dc42 - PING! Sorry to be a pest but I'm hang-fire on installing these steppers until you tell me if I should return them and get the 17hs19-1684s1 ? They're much more expensive, and if the 17hs19-2004s1 will work running at a lower current in the box I linked in my reply to you (above)... Thx!

    @zapta - Looked into the bed setup today on the CR-10S, I see what people are talking about on there being 4 copper pads. But visual inspection and checking with my bench DVM reads it out at .64Ω which means it's 12v. Yes, you can run it on 24v, it's just a heater, but the thing would pull down the 24v supply a bunch, they run higher resistance on the 24v rated beds. I'll stick with my dedicated 12v supply, it's a spare anyway.

    Oh - those second set of pads? They are connected to the same heater, I'm planning on upgrading the wires to silicon covered 12 AWG so I'll use all four pads, they're just in parallel. Would have been nice if they were a second heater. ☹


  • administrators

    @puterpro said in Upgrading CR-10S Steppers & PS to 24v Suggested Z replacement:

    @dc42 - PING! Sorry to be a pest but I'm hang-fire on installing these steppers until you tell me if I should return them and get the 17hs19-1684s1 ? They're much more expensive, and if the 17hs19-2004s1 will work running at a lower current in the box I linked in my reply to you (above)... Thx!

    I see that StepperOnline is currently offering the 2004 at 18% discount, which is why it costs less than the 1684.

    If you intend to stay with the Duet Maestro then the -1684 is a safer choice, because you will be able to run it closer to its rated current. For the Duet WiFi/Ethernet, the -2004 would be a better choice. But I used to run the -1684 at 800mA, which is less than half its rated current. By the same token, the -2004 may be work reasonably well at 1A, which is no problem for the Maestro.



  • @dc42 - Thanks! Makes sense. I'll try them at 1 amp. I'll probably buy a Duet Wi-Fi (or whatever secret thing you're currently working on now ...) when I build my CoreXY and move the motors there.

    Did you peek at the case I uploaded to Thingiverse?


  • administrators

    @puterpro said in Upgrading CR-10S Steppers & PS to 24v Suggested Z replacement:

    Did you peek at the case I uploaded to Thingiverse?

    Yes I did. I am a little concerned that at the end near the anged fan, it looks to me that there isn't a good path for air flowing underneath the PCB to cool the drivers. Shouldn't the fan slot be at the bottom, not the top?



  • There's a slot above and below, kind of hard to see on the STL viewer. If you hit "Thingiview" at the top and rotate it so see the front you can see the mounting post through the bottom hole.

    I just printed the new revision (posted late yesterday) last night, came out much better than original.

    I agree the slot on the bottom should be a bit larger, the bulk of the air from the front angled fan should go under the board's drivers, the rear fan should handle the lesser flow across the board from the side vents.

    I'll edit the divider to bias it that way, thanks for confirming what I was already thinking. Going to mount a fan today and check the flow.


  • administrators

    @puterpro said in Upgrading CR-10S Steppers & PS to 24v Suggested Z replacement:

    There's a slot above and below, kind of hard to see on the STL viewer. If you hit "Thingiview" at the top and rotate it so see the front you can see the mounting post through the bottom hole.

    I see it now.


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