That’s actually exactly my point, steppers are objectively inferior to servos, but servos are too expensive compared performance gains for hobbyists.
Comment on Why do we still use stepper motors?
ShepherdPie@midwest.social 10 months agoAll the DIY CNC machines I’ve seen use larger stepper motors. The commercial CNC machines I’ve seen can cost $10,000 to hundreds of thousands.
DreadPotato@sopuli.xyz 10 months ago
Hacksaw@lemmy.ca 10 months ago
I don’t think the sentence you have is entirely accurate.
High cost servo systems (motor, encoder, and driver) are superior to high cost strippers for dynamic positioning. Even that can be tenuous for low torque low speed applications, or nanoscale applications, etc… Certainly for 3 axis table/gantry CNC systems (router, laser, 3d print) for commercial/industrial grade applications servos are superior.
If you’re aiming for a hobbyist price point steppers have better dynamic positioning performance than servos. You can build a $300-$1000 3d printer with servos, but especially at the low end, it’s not going to be good.
DreadPotato@sopuli.xyz 10 months ago
But that just highlights the statement/question in my OP, it’s just cost prohibitive to use servos as a hobbyist. You can as a hobbyist get a better system with servos, but not for a reasonable price point.
semperverus@lemmy.world 10 months ago
Do you want to have a conversation, or do you want people to agree with you?
Your post is phrased like a question, but your comments feel like the opposite.
Strykker@programming.dev 10 months ago
If you are buying industrial grade 1000+ dollar servos you are no longer “hobbyist” in the price range that hobby level 3D printers exist steppers are more precise than servos.
Eranziel@lemmy.world 10 months ago
I don’t know why you’re getting down voted. You’re correct, steppers are used due to cost.
TwanHE@lemmy.world 10 months ago
You will not get a better system when using servos no matter the price point at the moment. People have tried and failed just because the software support isn’t there yet for 3d printing.
The biggest issue I’m aware of is matching the timing between the extruder stepper and the servos that do the XY motion.
Which isn’t apparent at lower speeds but at higher speeds you can notice they’re no longer in sync which leads to all sorts of issues and artifacts.
I’m currently waiting on some 3 phase steppers and drivers to test to hopefully get something with less speed deviation than a normal 2 phase stepper and more reverse torque but don’t cost too much and are still easily driven by connecting a driver to your boards step/dir output.
aSingularFemboyHooter@sh.itjust.works 10 months ago
Which makes them superior, which is why they are used. Cost can’t be ignored any more than the torque or speed, speccing parts that are considerably more expensive that achieve equivalent results is bad engineering unless you have a very specific application that requires it.
If it was ‘objectively inferior’ we wouldn’t use them. You build to your requirements, not by playing top trumps with competing technologies while ignoring the cost.
curiousPJ@lemmy.world 10 months ago
It seems like the argument is that at a lower price bracket, stepper motors offer higher performance than what a equivalently priced servo+encoder+controller combo can perform.
I felt like what I’m reading in this thread wasn’t matching up with that I see out in industry… Diamond turning machines are inherently low torque, low speed, AND nanoscale operations which uses servos for driving its respective axis. See precitech -youtube and in stark comparison Roeder’s 5axis optical mold machining. Wire EDM’s were all driven by servo motors until linear motors became popular. Even those famous JingDiao test samples are made on machines driven by servos.