MKS SERVO42C NEMA17 Closed Loop Stepper Motor Driver Low Noise for CNC 3D Printer Prevent Losing Steps Compatible with Gen L SGen L SKR 2 / V1.4 Turbo BTT Octopus V1.1 Mainboard

The controller board on the back of the stepper motor tracks when the printer gantry moves out of position. When I grab the hotend (while cold) and yank it to the side, it automatically moves back to its original position.

Great idea, but the product is not finished. It's buggy, which would be fine if the firmware was open source and we could fix it, but it's not. It's works 95% of the time, but 5% of the time it causes layer shifts. It often goes info a feedback loop driving the print head back and forth repeatedly until Marlin crashes. It's like the printer is having an epileptic seizure while on meth.Until the firmware is open sourced I would stay away. Without the firmware source you will have zero chance of fixing the bugs and it's clear the MKS is not going to fix them. They haven't even released a single firmware update to fix a single bug. The github site is empty, been empty, and most likely will remain empty of firmware source or update. This is a dead project.If you want closed loop, I would look elsewhere. I'm looking into linear scales or rotatory encoders to get a working closed loop control as Marlin has at least some support for them already. At the very least I would have the source code (Marlin) so I could fix/add any needed support. If I had known this was a closed source project I would not never bought these stepper controllers. I just saw a git hub site with a firmware directory and thought that the firmware source was available. But it was just a trick. The directory is empty. My fault for not checking first.It make matters worse one of the two cheep stepper motors failed and I had to replace it.

I picked this up because I thought it was their new version 2 model. Biqu put out a new model and then i saw this one and figured it's their new model also. Well it is but it isn't. It's their new old model V1 where V2 of this closed loop stepper has way more function and use. I sent it back and will wait until I find V2 of this model. Not going to pay top price for 2 year old technology.

the hall effect encoders on these is too slow for fast moving 3d printers. Don't waste your money Hanpose has some nema 17 stepper/servo's with optical encoders. they'll cost more, but work better.

Only four stars because I can’t find a way to connect it to my laptop for manual control.

The media could not be loaded.  Dieser Schrittmotor ist ein Traum.Ich hatte Probleme mit Versatz in der Y Achse schon bei 100 mm Geschwindigkeit trotz TMC2209 Treiber.Das Bild mit dem klaren Dreieck zeigt es ganz gut.Schuld ist vermutlich auch das schwere Druckbett mit 300x300 mm und der Glasplatte auf dem Heizbett.Nun habe ich auf diese Motoren an X und Y umgerüstet und ich bin begeistert.Stark, schnell und leiser als mit dem Trinamics Treiber.In dem Video übertönt der Bauteile Lüfter leider alles, darum habe ich die Lautstärke Messung mit dem Handy gemacht.Die Vase auf dem Drucker stellt die Mechanik unter Stress bei der Druckgeschwindigkeit, aber wie zu sehen absolut genaue Layer und kein Shifting zu sehen.Der Umbau hat sich gelohnt.Eine Anleitung habe ich bei Thingiverse eingestellt.Erwähnt muss noch werden, das die Motoren fertig montiert und kalibriert geliefert worden sind, also einbaufertig.Der Einbau funktioniert allerdings nur, wenn tauschbare Treiber im Pololu Format auf der Drucker Mainboard verbaut sind!Bei fest verlöteten Chips keine Chance.