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A comment on Prusa MINI: Smart and compact 3D printer. Parent comment

Re:Prusa MINI: Smart and compact 3D printer by jrockway on Saturday October 12, 2019 @07:03PM (#21236971)
I think he is referring to a step motor controller as a "stepper". People love the fact that Prusa uses Trinamic drivers instead of no-name drivers.

I personally don't understand why step motor control is something that needs to be outsourced. Just stick an H-bridge between the microcontroller and the motor and improve the control algorithm with every release.

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Re:Prusa MINI: Smart and compact 3D printer by m0xte on Saturday October 12, 2019 @07:23PM (#21237052)
The “no name” drivers are a bit more complicated than an H bridge: https://www.pololu.com/file/0J450/a4988_DMOS_microstepping_d...

The typical H bridge has many failure modes and disadvantages which are handled by the controller ICs. Not to mention a lot less CPU overhead for the AVR running the show.

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Re:Prusa MINI: Smart and compact 3D printer by jrockway on Saturday October 12, 2019 @08:06PM (#21237255)
Yeah, you can get some feedback from the controllers easily (and then omit physical endstops).

I am waiting for a 3D printer that uses servo motors, though. So many failed prints come from not knowing where the extruder is. But you can just measure exactly where it is, rather than guessing based on how much current the motor used.

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Re:Prusa MINI: Smart and compact 3D printer by taneq on Saturday October 12, 2019 @09:31PM (#21237663)
Servos don’t actually gain you that much. If you’re meeting enough resistance to skip steps then your print is wrecked anyway.
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Re:Prusa MINI: Smart and compact 3D printer by imtringued on Sunday October 13, 2019 @04:12PM (#21242648)
Servos will easily triple the cost of the printer.
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Re:Prusa MINI: Smart and compact 3D printer by IshKebab on Sunday October 13, 2019 @02:53AM (#21238830)
I've done manual h-bridge style control and it just can't match a proper driver. You're going to get a ton more vibration and less power.

I use Leadshine ones normally. They're big but also very reasonably priced and work very well.

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