3DPrinting
3DPrinting is a place where makers of all skill levels and walks of life can learn about and discuss 3D printing and development of 3D printed parts and devices.
The r/functionalprint community is now located at: !functionalprint@kbin.social or !functionalprint@fedia.io
There are CAD communities available at: !cad@lemmy.world or !freecad@lemmy.ml
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No bigotry - including racism, sexism, ableism, homophobia, transphobia, or xenophobia. Code of Conduct.
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Be respectful, especially when disagreeing. Everyone should feel welcome here.
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No porn (NSFW prints are acceptable but must be marked NSFW)
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Do not create links to reddit
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If you see an issue please flag it
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No guns
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No injury gore posts
If you need an easy way to host pictures, https://catbox.moe may be an option. Be ethical about what you post and donate if you are able or use this a lot. It is just an individual hosting content, not a company. The image embedding syntax for Lemmy is 
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I disagree with all your points. What kind of servos are you talking about?
BLDC and AC servos maintain full torque at stop too, and have about 2-3× the torque of a stepper of similar size.
The only way a stepper can rival a servo for precision is with a high degree of microstepping, which is far from guaranteed positioning with open loop control.
I haven't directly compared response time between steppers and servos, but I would be extremely surprised if there's a significant enough difference to worry about. Most servo-controlled machines are larger and so are designed to accelerate slower than a printer, if that's what you mean. This is intentional because inertia is a thing you have to worry about, not because the servo reacts to command changes slowly.
There are valid reasons steppers are used on printers, but it's not because they have superior performance.
Huh, this is true about BLDCs as well? I remember seeing in a video that BLDCs tend to have very poor torque output when stopped and especially when at low speeds (due to very low efficiency requiring too high currents for drivers to supply), whereas AC motors have a pretty much flat torque curve until they get fairly fast. I'd be interested to know if this is true.
That sounds like a problem from using too small of a drive. Every torque curve I've seen for brushless DC or AC servos is constant torque from 0 to about 75% rated RPM, and then starts to drop off.
That sounds about right. You can technically achieve full torque at 0 RPM, but the current required for that might be very high (and may not be practical for the small size, power limits, and cost of a 3D printer). I know this is a problem in Asian import mini-lathes - if you run the spindle too slow you won't get much torque out because the driver can't supply enough current.