Got my SM 2.0 a few days ago and only got a chance to have a play with it.
I am experiencing a hissing noise, constant and with the same pitch from what i suspect to be the linear modules (close to heating bed). Is anyone else having this or should i get in touch with Snapmaker?
The sound… sounds like a fan but it is located around the Y splitters area, so it can’t really be a fan.
I have also upgraded the firmware today to the most recent one, and for a few seconds the hissing stopped completely, while the screen was saying Updating the modules / controller.
I have a guess that what you’re hearing is a low-level arc discharge.
I’ve seen a photo here on the web site of a charred path through the circuit boards next to the stepper motor inside the linear module. It looks pretty clear that it’s an arc fault through an electrical short. Given what you’ve said in combination with these photos, my suspicion is that you’re hearing the early stages of what’s going to be a terminal failure for that module.
Your report that this stopped when the firmware was being updated is consistent with this hypothesis. During a firmware update, the hardware would be completely powered down, removing the current source that powers the arc.
If you’d like to verify this without disassembling the linear module, use a mechanic’s stethoscope. This is just like a doctor’s one but with a metal rod that you touch to a part to hear what it’s doing inside under motion. Harbor Freight has a perfectly serviceable one for $5 when it’s not on sale for $2. Touch the probe to the linear module. If my suspicion is correct, the sound will be loudest near the circuit boards, about two or three inches from the end of the extrusion near where the cable exits it. The sound would be present along the whole linear module at lower volume, and barely audible if at all on the other modules.
If you are printing or moving pretty slow, you will get some resonance noise because of the all metal design.- If this is the case, try various print/move speeds. - Make a video to get sure this is your problem, please
I have some antivibration mat under my machine which makes it less noisy.
It could also be the linear modules holding their position - mine also make a bit of a hissing sound. I wouldn’t describe it as a buzzing sound that I would normally associate with an arc
OMG LOL it’s not partial discharge. The energies involved here are not even within 2 orders of magnitude of being enough to generate audible partial discharge.
It’s normal, you’re hearing the magnetostriction of the stepper motor at the carrier frequency of the driver output.
Just wanted to thank you all for your replies and views on the matter.
For further clarification, the same hissing noise happens as soon as the printer gets powered on and remains the same all the way through its use. (Though i have to admit it becomes harder to differentiate the sounds while the printer is in operation).
The hissing however if the same even if the X,Y,Z coordinates of the head are different. Basically it hisses the same wherever the head is - for example during the calibration process where noise levels are fairly low, the hissing i am describing is constant.
I will look into recording a video so you guys can compare with your machines.
PS: i am not suggesting there is a problem with mine per say, but rather wanted to find out if the sound is normal and others are having it too.
You can disable the stepper motors with M18 to make the sound stop. You’ll have to rehome with G28 before doing anything again. Some people add M18 to the end of their gcode files so the machine goes quiet when it’s done printing.
If the noise is a hissing or fiping sound and occurs very clearly when the axes are at a standstill and changes when the bed or head is pressed lightly, it is only the motor brake. the steppers are controlled by pwm and the whole machine then works as a loudspeaker for the motor coils. this becomes clear when switching on the printer. shortly after switching on, the machine jerks exactly at the moment when the control of the axes is started and exactly then the noises start
The most common causes of arc fault are loose connectors and (internally) frayed stranded wire. No need to invoke dielectric breakdown as an initial fault. Arc faults generate ozone, which chemically attacks insulators, so you later can get breakdown of insulators as they become compromised. There’s a reason, now that AFCI (arc fault circuit interrupters) have gotten inexpensive, that they’ve started to be mandated in building codes.
Given the general poor quality control on these SM products, I wouldn’t at all be surprised that there are, say, a number of bad crimps on a high-current connector.
Air is a dielectric, small arcs through air are PD as the air has broken down.
120V AFCIs are applied on systems with peak voltages of 170VAC. The PD occurs once every half cycle at the wave maximum and minimum voltage.
Not sure either of those apply here, but ¯\_(ツ)_/¯
Regardless, essentially telling someone new that a well understood sound stepper motors make is arcing and possibly going to burn their house down is misleading.
That’s an arc discharge. Partial discharge is different. To quote the Wikipedia article you cited: “partial discharge is a localized [dielectric breakdown] (which does not completely bridge the space between the two conductors)”.
That’s the peak supply voltage, not the peak voltage that occurs when you get an arc fault. You get much higher voltages when a contact breaks because of inductive kick. The inductance here is the parasitic inductance of the physically-realized circuit, even where that are no coils parts as designed-in inductive circuit elements. For example, the contact points on DC relays are notorious for tiny arcs when the contact breaks; it’s why you see 120 VAC and 24 VDC ratings on the same relay.
I have this sound as well, I can still hear it while the enclosure is closed, and obviously it’s louder than the power supply that is not in the enclosure. Snapmaker 2.0 350 Hiss
I have the same sound as you in the video, however it does stop when I send M18 and starts again when it re-homes. Does this mean I have nothing to worry about? Mine is louder at times, not so noticeable at others. Also, it didn’t do this when I first set it up and printed/lasered, but has started within a week of having it.
I’ve still not used the Snapmaker yet, but I did update the firmware and noticed it stopped while updating the modules, after watching a few videos I don’t think it’s normal, I’m sending in a support email now.
Zero Zhao (Snapmaker)