How to use the 'stealth' printer limits of Prusa Slicer  

RE: How to use the 'stealth' printer limits of Prusa Slicer

You dont.

Stealth mode was a Prusa creation, it was added specifically to their printers and isn't/wasn't part of any official specification (not sure if this is still the case).  As such there are no specific gcode commands for stealth limits, (ether as Mxxx or as a parameter to the standard M limit codes)

As the choice to run in stealth is set on the printer and only prusa printers were concerned with this there was no need to set them in the top, in fact only the normal ones can be included in standard gcode because you can only include 1 set using normal M commands.

You may be asking 'then how does the printer slow down in stealth mode then'.  Answer is that ALL of the settings from your profiles are stored at the end of every gcode file generated.  Your stealth capable printers can read those just as easily as any other line of text.

For example, from a gcode file I had kicking around for my Mk3.

; machine_max_acceleration_e = 5000,5000
; machine_max_acceleration_extruding = 1250,1250
; machine_max_acceleration_retracting = 1250,1250
; machine_max_acceleration_x = 1000,960
; machine_max_acceleration_y = 1000,960
; machine_max_acceleration_z = 1000,1000
; machine_max_feedrate_e = 120,120
; machine_max_feedrate_x = 200,100
; machine_max_feedrate_y = 200,100
; machine_max_feedrate_z = 12,12
; machine_max_jerk_e = 1.5,1.5
; machine_max_jerk_x = 8,8
; machine_max_jerk_y = 8,8
; machine_max_jerk_z = 0.4,0.4

Note the 2 sets, one is normal the other stealth.

RE: How to use the 'stealth' printer limits of Prusa Slicer

Thanks @Neophyl, this solves the mystery.

Is there a gcode to switch the printer to the stealth mode, something I can include in the startup gcode?

RE: How to use the 'stealth' printer limits of Prusa Slicer

Not as far as I know but I'm not really familiar with any additions they may have done for the Xl's. Core1 etc as I don't own one.

If you want to decide the speed at slice time the simplest thing is to create an extra printer profile and set the normal speeds in there to the stealth ones. Then slice with the appropriate printer selected. No need for a switch then. Of course the normal way is to just slice using a Print profile that has suitable speeds for all the moves set as you like rather than relying on the printer maximums (which some printers don't even use anyway)

btw the reason I know this sort of stuff is I regularly skim the Prusa Slicer github repo. For example this now closed issue https://github.com/prusa3d/PrusaSlicer/issues/6161

For a gcode command to be supported it would first need implementing in whatever printers firmware and then in the slicer to match. These sorts of requests have to be made to the firmware providers. As yet you haven't mentioned what printer you are using. Prusa printers firmware githubs are located here for the older boards (einsy) https://github.com/prusa3d/Prusa-Firmware/issues and here for the newer ones like MK4.XL (Buddy Board) https://github.com/prusa3d/Prusa-Firmware-Buddy/issues

There are a few existing for stealth mode switching on the Buddy repo already but they seem to be asking for control via Prusa Connect or on a schedule for overnight use.

The older firmware repo from a cursory search showed this one https://github.com/prusa3d/Prusa-Firmware/issues/2477 as the most relevant. There are others.

RE: How to use the 'stealth' printer limits of Prusa Slicer

Thanks @Neophyl, my printer is CORE One so xBuddy controller.

I would expect it to have a gcode command to control its mode.

RE: How to use the 'stealth' printer limits of Prusa Slicer

Isn't it related to a StealthChop on newer printers? See https://help.prusa3d.com/article/buddy-firmware-specific-g-code-commands_633112 gcode M569, some of them have it enabled by default already mini).

RE: How to use the 'stealth' printer limits of Prusa Slicer

Posted by: @_kaszpir_

Isn't it related to a StealthChop on newer printers? See https://help.prusa3d.com/article/buddy-firmware-specific-g-code-commands_633112 gcode M569, some of them have it enabled by default already mini).

It seems that a change in the LCD stealth mode setting invokes M9140 or M9150. 

https://github.com/prusa3d/Prusa-Firmware-Buddy/blob/818d812f954802903ea0ff39bf44376fb0b35dd2/src/gui/MItem_tools.cpp#L170

And according to ChatGPT (?) these commands control also the Trinamic StealthChop mode on all axis. 

I turned the stealth mode on the LCD and am trying it now as my default printing mode. So far I like it.

RE:

in that case it does something different:
https://github.com/prusa3d/Prusa-Firmware-Buddy/blob/master/src/marlin_stubs/PrusaGcodeSuite.hpp#L137
which leads to
https://github.com/prusa3d/Prusa-Firmware-Buddy/blob/master/src/marlin_stubs/M9140_M9150.cpp#L21
and finally:
https://github.com/prusa3d/Prusa-Firmware-Buddy/blob/master/lib/Marlin/Marlin/src/module/planner.cpp#L155

so it just sets different speeds only, and not touching StealthChop?

RE: How to use the 'stealth' printer limits of Prusa Slicer

It's possible that Prusa's 'Stealth mode' and Trinamic's 'Stealth Chop' are two independent concepts.

'Silent mode' would be a better name in my opinion, regardless if it uses Stealth Chop or not.