Resonance, spreadCycle and stealthChop
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@matt3o Nothing much leaps out at me from your config.g file. I note that you are using DAA (M593). Never had the need to use it myself - what happens if you take it out? Better/same/worse?
The motor currents look low if your motors are 2Amps but I seem to recall that you'd played around with different settings.
Unrelated to your resonance problem but your instantaneous speed change threshold (jerk) settings are low. That's likely to slow down segmented arc moves. (I use 900 as opposed to your 300). Your extruder jerk at 120 will play havoc with pressure advance if you start using that. Suggest you set it really high so that it can't interfere with print speeds (I use 3600).
Sorry that I can't be much more help with your vibration issues.
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@deckingman thanks for your feedback, really appreciate all your help. I played with currents/speed/accel/jerk. I tried anything I could including DAA. Nothing really helps. Only setting amperage incredibly low (below 1A) somehow mitigates the problem.
Regarding the extruder, thanks for the heads up... I wish I was already optimizing the extruder
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@matt3o Probably a bit late now, but I wonder if changing micro stepping to (say) 32x or 64X would have had any effect. Strange that reducing motor currents helped .......
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@deckingman said in Resonance, spreadCycle and stealthChop:
@matt3o Probably a bit late now, but I wonder if changing micro stepping to (say) 32x or 64X would have had any effect. Strange that reducing motor currents helped .......
tried that too from 1 to 256 microstepping. with/out interpolation. nope.
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Have you try to tackle the mechanical resonance problem by mechanical means? This is something that good mechanical engineers should know how to do.
Here is a demonstration of mechanical resonance, there are no explicit 'pulses' or 'steps' but it resonates never the less.
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Try the motors, its worth a shot. What you showed in the video its very similar to how the Toolchanger behaved a certain speeds. The frame itself isn't a source of vibration, it can only resonate. For my case its clear the motors are adding the vibration to the system.
StealthChop is another way to prove its the motors/drivers adding the noise. Maybe it wouldn't achieve your performance goals but it would be a good data point to show that the mechanical system can indeed be quiet.
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@garethky said in Resonance, spreadCycle and stealthChop:
StealthChop is another way to prove its the motors/drivers adding the noise. Maybe it wouldn't achieve your performance goals but it would be a good data point to show that the mechanical system can indeed be quiet.
oh yeah stealthchop is completely quiet, but I start dropping steps at 120mm/s which is lower than a standard travel speed. I'll give the motors a shot... I spent already a fortune on this thing
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on your corexy design , did you test the motion system before connecting the belts ?
maybe the rails are not 100% parallel .on your cartesian design , i'm not sure if its a good idea to run the rails unsupported like that .
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@hackinistrator said in Resonance, spreadCycle and stealthChop:
on your corexy design , did you test the motion system before connecting the belts ?
maybe the rails are not 100% parallel .ooooh yeah it took forever to align those rails
in the new motion system I have even more rails. I'm becoming an export at aligning rails!@hackinistrator said in Resonance, spreadCycle and stealthChop:
on your cartesian design , i'm not sure if its a good idea to run the rails unsupported like that .
I dunno, they are pretty hefty rails. I hope they will be fine. If it doesn't work I'll put them on a baker.
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this is funny because on my config (core XY tmc2209 all metal frame and parts) i had to force the spreadcycle because stealthchop was noisy at more than 60mm/sec
and what i think is that stealhchop induce some counter force to reduce the sound (and so on a move you don't have a really perfect sinus wave on your motors wires) but the problem is taht they mess together when using a core XY, because both the variations from each motors arrives in the x cage and from my observations this is from the sound comes. for me the stealthchop mess with itself because it's not supposed to work on core XY. and that's why you got wierd noise when moving both motors at the same time and not on diagonals.
and i have to admit i can live woth spread cycle because honnestly the fans are louder, by far.oh and on the BLV mgn FB page when io talk about my problem the first thing people said was "disable stealthchop, it suxx with marlin" as they thought i was on marlin.
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that's interesting. just a note though
@psychotik2k3 said in Resonance, spreadCycle and stealthChop:
and i have to admit i can live woth spread cycle because honnestly the fans are louder, by far.
it's not a noise issue. everything shakes!
but anyway with the new kinematics I solved the issue. Don't tell @dc42 but I also installed klipper on the duetwifi 
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@matt3o said in Resonance, spreadCycle and stealthChop:
I also installed klipper on the duetwifi
How does this work, did you replace the Duet's firmware with a dumb version that is controlled by the Klipper SBC?
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@zapta said in Resonance, spreadCycle and stealthChop:
How does this work, did you replace the Duet's firmware with a dumb version that is controlled by the Klipper SBC?
yes, you have to replace the original firmware with Klipper's. I like RRF "all is Gcode" philosophy, but over all I prefer klipper and I don't think I'll revert back, at least for now.
