Very loud stepper motors

N3XT3D

Hello everybody.

I have a problem with my Corexy printer. This is absolutely loud, especially at speeds greater than 60mm/s, which increases with speeds up to 200mm/s.

I have added a youtube video so that you can see for yourself here.

I have installed a DuetWifi board and a Siemens SITOP 24V 20A power supply, as well as genuine HIWIN-rails.

M350 is checked. Interpolation is switched on.
I also modified M569, but it didn't have much of an impact.

Here is my config.g

; Configuration file for Duet WiFi (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v2.1.4 on Sat Dec 28 2019 21:53:43 GMT+0100 (Mitteleuropäische Normalzeit)

; General preferences
; Aktuelle Duet Wifi Firmware Version: 3.1.0 - Stand: 17.05.2020
; Paneldue Information: Hardware Version: Panel Due v3.0a - 57600 baud - aktuelle Version: 1.24 - Stand: 11.05.20
M575 P1 S1 B57600														; set Panel Due Baudrate to 57600
G90																		; send absolute coordinates...
M83																		; ...but relative extruder moves
M550 P"XY Cube"															; set printer name

M667 S1																	; select CoreXY mode

; Network
M552 S1																	; enable network
M586 P0 S1																; enable HTTP
M586 P1 S0																; disable FTP
M586 P2 S0																; disable Telnet

; Drives
M569 P0 F3 S1															; physical drive 0 goes forwards - Changed TOFF for reduced motor noise F4 is default
M569 P1 F5 S1 															; physical drive 1 goes forwards - Changed TOFF for reduced motor noise F4 is default
M569 P2 F3 S1															; physical drive 2 goes forwards - Changed TOFF for reduced motor noise F4 is default
M569 P3 S1																; physical drive 3 goes forwards
M584 X0 Y1 Z2 E3														; set drive mapping
M350 X16 Y16 Z16 E16 I1													; configure microstepping with interpolation
M92 X200.6197 Y200.4387 Z1600.00 E412.493								; set steps per mm
M566 X500.00 Y500.00 Z30.00 E400.00										; set maximum instantaneous speed changes (mm/min)
M203 X12000.00 Y12000.00 Z150.00 E2100.00								; set maximum speeds (mm/min)
M201 X2000.00 Y2000.00 Z100.00 E5000.00									; set maximum accelerations (mm/s^2)
M204 P1000 T2000														; set accelerations of printmoves to 1000 and for travelmoves to 2000 (mm/s^2)
M906 X1600 Y1600 Z1600 E1600 I30										; set motor currents (mA) and motor idle factor in per cent
; M593 F32																; Set Dynamic Acceleration to cancel ringing at 48 Hz
M84 S30																	; Set idle timeout
M671 X30:270:30:270 Y270:270:30:30 P0.7									; Define Bedleveling screws, 0,7mm pitch

; Pressure advance
M572 D0 S0.07															; Pressure advance - 0.113

; Axis Limits
M208 X-11 Y0 Z0 S1														; set axis minima
M208 X306 Y321 Z500 S0													; set axis maxima

; Endstops
M574 X1 S1 P"xstop"														; configure active-high endstop for low end on X via pin xstop
M574 Y2 S1 P"ystop"														; configure active-high endstop for high end on Y via pin ystop
M574 Z1 S2																; configure Z-probe endstop for low end on Z

; Z-Probe
M558 P1 C"zprobe.in+zprobe.mod" H3 F100 T12000 I0 B0					; set Z probe type to unmodulated and the dive height + speeds - A5 S0.02 optional fuer multiprobe selbsttest
G31 P500 X-2 Y-16.4 Z3.05												; set Z probe trigger value, offset and trigger height - 3.05 for CFK; 3.02 for Buildtak; 2.724 for Powdercoated Springsteel; 3.152 for ALU -  Wert kleiner wird Abstand Größer.
M557 X30:270 Y30:270 S40												; define mesh grid

; Heaters
M308 S0 P"bedtemp" Y"thermistor" T100000 B3950 A"Druckbett"				; configure sensor 0 as thermistor on pin bedtemp - A"Printbed"
M950 H0 C"bedheat" T0													; create bed heater output on bedheat and map it to sensor 0
M143 H0 S100															; set temperature limit for heater 0 to 100C
M307 H0 A154.1 C2269.2 D1.0 V24.0 B0 S1.00								; disable bang-bang mode for the bed heater and set PWM limit
M140 H0																	; map heated bed to heater 0
M308 S1 P"e0temp" Y"thermistor" T100000 B4725 C7.06e-8 A"Nozzle"		; configure sensor 1 as thermistor on pin e0temp - A"E3DV6 Hotend"
M950 H1 C"e0heat" T1													; create nozzle heater output on e0heat and map it to sensor 1
M143 H1 S280															; set temperature limit for heater 1 to 280C
M307 H1 A368.0 C157.4 D3.7 V24.0 B0 S1.00								; disable bang-bang mode for the nozzle heater and set PWM limit

; Fans
M950 F0 C"fan0" Q250													; create fan 0 on pin fan0 and set its frequency
M106 P0 C"Bauteil Lüfter" S0 H-1										; set fan 0 name and value. Thermostatic control is turned off
M950 F1 C"fan1" Q500													; create fan 1 on pin fan1 and set its frequency
M106 P1 C"Heatbreak Fan" S1 H1 T45										; set fan 1 name and value. Thermostatic control is turned on

; Tools
M563 P0 D0 H1 F0														; define tool 0
G10 P0 X0 Y0 Z0															; set tool 0 axis offsets
G10 P0 R0 S0															; set initial tool 0 active and standby temperatures to 0C

; Limit axis movement
M564 H1 S1														; movements only work with homed Axis; H1 = forbid movement of axes that have not been homed; S1 = limit movement within axis boundaries

; Custom settings are not defined
M912 P0 S-4														; Set correction for CPU Temperature

; Miscellaneous
M911 S23 R28 P"M913 X0 Y0 G91 M83 G1 Z1 E-1 F1000"				; set voltage thresholds and actions to run on power loss

What struck me: The diagonal speed is permanently limited to 141 mm/s.

I have already changed the X and Y motors, but this did not bring any improvement.

I would be very grateful for comments, ideas and help.

Thanks

PDBeal

What motors are you using? 1.6A seems rather high for motor currents.

I'm basing this on my steppers on my CoreXY are rated for 1.6A but I have them set to 600 in my config and they're as quiet as can be. It might not be related, but worth checking at least.

N3XT3D

Thank you for the fast answer. I use the following Motors.

Unfortunately, I do not know whether the amperage also affects the noise. And also strange that the speed with only one motor is limited to 141 mm/s.

If a change would help, I would do it right away

N3XT3D

@PDBeal I just adjusted the amps to M906 X800 Y800 Z1600 E1600 I30 and this had a big effect on the noise! Would it make sense to buy motors with different specifications?

But first: great help!

Phaedrux

I use those same motors on my corexy at about 1700ma during printing and I can't say they are overly loud. But I also use some cork pads and printed motor mounts which dampen them. A big part of the noise is going to come from resonance with the frame, so if you can decouple the motors it can help a lot. A simple cork pad works ok, and there are purpose made nema17 rubber isolating mounts.

As for the corexy max speed attained when using a single motor, this thread may be helpful.

https://forum.duet3d.com/topic/8697/corexy-speed-constrained

theruttmeister

@N3XT3D said in Very loud stepper motors:

Would it make sense to buy motors with different specifications?

If you can hit the speeds you want with the lower current, no.
Motors with different current rating will also have different torque etc. Its not unusual to have a current rating higher than you are actually setting for the driver.

Also, your steps-per-mm in X and Y... seem odd. Are you running printed pulleys or something? I would expect with a coreXY machine that they would be identical (and unless you are running MXL belts, whole numbers).

If you are looking to increase speed, going to larger diameter pulleys is the most effective choice. I don't believe anyone is getting even close to the precision that 200 steps/mm is promising.

N3XT3D

@Phaedrux thaks for your answer!

I have already thought about such rubber dampers, but I also imagine a weak point in the accuracy, because the motor shaft no longer remains exactly in one position due to the rubber. Or whether the shaft is not even crooked due to the tensile load on the toothed belt.

N3XT3D

@theruttmeister I use 16 teeth aluminum pulleys. With these values of steps / mm I get the best dimensional accuracy of the printed parts. I also find it strange that these values are not identical. They are nominal 6mm wide GT2 belts.

The speed of the printer is a nice to have for me, but the main thing for me is to reduce the noise.

I thought that if I lower the amperage of the motors, I only lose the motor's holding power and not my speed. Ok, as the speed of the motor increases, the holding force also drops a bit, but I think the effects are not that big.

What would be more sensible to install a large, powerful, new motor like this 65Ncm and operate it with lower amperes (because of the volume and still maintain the holding power) or to provide the current motors with dampers and maintain the 1600 mA? It would be important to me not to lose anything in accuracy. I don't know if the motor in the rubber damper can't move too much.

Phaedrux

@N3XT3D said in Very loud stepper motors:

I don't know if the motor in the rubber damper can't move too much.

It's actually quite stiff rubber. I don't think you'd get much more flex then you would from belts.

N3XT3D

@Phaedrux said in Very loud stepper motors:

@N3XT3D said in Very loud stepper motors:

I don't know if the motor in the rubber damper can't move too much.

It's actually quite stiff rubber. I don't think you'd get much more flex then you would from belts.

Thank you. I will buy and try such dampers. At the other end of the motor shaft I have a ball bearing for stiffening. If the damper is installed, the motor shaft will probably no longer reach into the ball bearing. But I will definitely test and report it.

zapta

@N3XT3D said in Very loud stepper motors:

I will buy and try such dampers.

They work very good on my HEVO and significantly reduced the noise. You can estimate the expected noise reduction by removing the belt and then running the motor, once attached to the frame and once held in your hand.

BTW, I like your printer.

N3XT3D

@zapta said in Very loud stepper motors:

@N3XT3D said in Very loud stepper motors:

I will buy and try such dampers.

They work very good on my HEVO and significantly reduced the noise. You can estimate the expected noise reduction by removing the belt and then running the motor, once attached to the frame and once held in your hand.

BTW, I like your printer.

Many thanks. I will install the dampers tomorrow as soon as they are in the mail. I will then link a video with the current status. I hope that the dampers bring the hoped-for success.

theruttmeister

@N3XT3D said in Very loud stepper motors:

@theruttmeister I use 16 teeth aluminum pulleys. With these values of steps / mm I get the best dimensional accuracy of the printed parts. I also find it strange that these values are not identical. They are nominal 6mm wide GT2 belts.

I suspect you are actually either compensating for something that isn't square in the machine, or you are in the noise of your measuring equipment.
Larger pulleys might produce slightly different results just because you will be spreading any potential error over more teeth. Or it might even be variability in the motors...
Either way, not important.

The speed of the printer is a nice to have for me, but the main thing for me is to reduce the noise.

I thought that if I lower the amperage of the motors, I only lose the motor's holding power and not my speed. Ok, as the speed of the motor increases, the holding force also drops a bit, but I think the effects are not that big.

What would be more sensible to install a large, powerful, new motor like this 65Ncm and operate it with lower amperes (because of the volume and still maintain the holding power) or to provide the current motors with dampers and maintain the 1600 mA?

Ok. Holding torque is only important for holding position, torque during moves is pullout torque and is the relevant thing.
Torque is a product of both current and motor speed, as speed goes up, torque goes down. Its because it takes time for the magnetic field to generate the torque, increasing the voltage helps because higher voltages form magnetic fields faster.
That motor is also generating more torque because its 1.8 degree, not 0.9. That means the teeth inside the motor are larger (because there are fewer of them) and so you get a stronger field.
The holding torque is misleading, its 50% higher... But if you look at the torque curves (there's a link on the product page) and compare the two motors, you'll see that the pullout torque at 450 rpm is very similar: 3500 vs ~3750 gf.cm.
Part of that will be because one motor is being driven full step, the other half step.
And if you reduce the current limit, you reduce the pullout torque. Reduce it enough and you'll lose position.

Which is all a long way of saying, maybe.
The windings are not wildly different, but there are 3 potential outcomes I would expect:

Not noticeable change. None. The function just the same as the first motors.
The windings are different enough that the motors resonate at the wrong frequency and make a nasty noise.
They generate enough additional torque that you can under-drive them and they are quieter.

Your call on if its worth the cost to see, but there's no better answer than testing them out.

If you are working on noise its hard, because changes that seem simple may well cause the motors to make noise at a much more annoying frequency.
I once helped modify a printer's electronics to make the stepper drivers run at 16kHz. Don't do that, its a horrible sound.

The quietest printer I have built so far uses NEMA23's. When you push it, it will move at speeds and accelerations that are genuinely dangerous. But if you are printing at normal speeds the loudest thing by far is the 40mm fan cooling the head.
If you really want to get the noise down as low as possible, I'd suggest going that route, NEMA23's under-driven. Not a drop-in option though.
I suspect that the lower noise is mostly because that printer is dense, all milled parts and big extrusions. Its an old CNC maxim, if you want to reduce vibration, add mass.

The dampers are by far the best first option.

N3XT3D

@theruttmeister I also believe that these minimal deviations from the 200 steps / mm are negligible.

Thank you for the detailed and very instructive explanation!

So I'll try the motor dampers first. If that does not bring the desired success, I will test the other motors.

The NEMA 23 motors are a bit too big for my printer. Even if it is processed relatively sturdy, it would not be able to withstand the resulting forces without the printing result suffering.

It doesn't have to be whisper-quiet, but you shouldn't be able to hear the printer 3 rooms further at 200 mm/s.
In a rented apartment, printing overnight is so completely impossible, which I would like to do. In addition, the loud noises of the printer in the apartment are very disturbing in the long run. I would be absolutely satisfied with a normal noise level.

In any case, thank you for the help and the effort with the explanation. Really great. I will report what the change brought with the dampers.

N3XT3D

@theruttmeister so the problem with the noise no longer exists.

The dampers have had a huge impact. But the change from the 0.9 ° step angle to the motors with 1.8 ° step angle had an equally great effect. Many thanks for the help. Here is the video with the current state.

The printer is now quieter and faster, with the same current for the motors.

Phaedrux

That's a substantial difference!

N3XT3D

@Phaedrux said in Very loud stepper motors:

That's a substantial difference!

Absolutely. This is really crazy. Thanks to all for the help. Now I am happy.

theruttmeister

@N3XT3D
Exellent.
With Trinamic drivers, that's what you should be able to get to!

You are lucky you missed the bad old days of Gen3 reprap electronics... Makerbot Cupcakes were LOUD.