I initially sent this to Edwin in a message as I didn’t want to freak anyone out. In my defense I had a bit of a buzz and the loudness of it freaked me out. My calm frame of mind as an electrical engineer and computer engineer only came after the buzz was gone lol.
I turned on the machine and it booted up as normal, all status lights were green, no issues. But as soon as it finished booting the power supply went haywire and sounded like a transmission stripping a gear or a chainsaw. It was not a linear module as I hurriedly poked my head in the enclosure, the noise was coming from the outside. Quickly peaked at the touch screen and all status lights were still green, put my head near the power supply and placed my hand on it and I could feel it. I immediately switched the power off.
Waited a little, turned it back on and I cannot get it to repeat, homed the modules and went smoothly as can be. However now there is a slight buzzing sound coming from the power supply which is not a vibration resonance from the power supply to the enclosure roof panel as I picked it up and it still was buzzing, kind of sounded like the fan blades edges hitting something oh so slightly and so I shut it off for fear of a bad power failure (again, buzzed). Much later after my buzz wore off (and no I was not going to operate it when drinking, only turned it on to check something) i thought there’s really only one thing that moves inside a PSU. Pretty sure the fan bearing has gone bad. I’ve ordered the fans for the noise reduction upgrade on Amazon. Before it happened I had been trying to track down the slightest high pitch noise coming from my work area where I have many electronics, and the sound would change harmonics like it was spinning. I knew it was the sound of a failing fan bearing but couldn’t place it exactly as I have tinnitus in my left ear. My idiot brain just never connected the two til the buzz wore off.
Yep, I’m hearing the same thing, it’s the inner fan cooling the actual PSU board for me. I’ve been running my snapmaker literally non stop for the past 2 weeks though, so I suspect that’s the cause.
Once I’m done with the current project I plan to take the PSU apart (again, I already took it apart once to do the noctua upgrade, and again when it started making this new noise) and replace or maybe just grease the fan.
Shouldn’t make a difference. The fan is rated for way more hours than that. I’ve slowed down over the past month or so now that works been getting busy again post-covid, but I ran mine pretty much 24/7 from the time I got it in July until late February. Only powered down to cycle power. They’re cheap fans though so they might fail prematurely.
Sorry for the late reply as I was busy with the tickets this morning. In order to rule out the machine and those linear modules, you can boot the power unit without connecting the machine.
No worries you gotta enjoy your weekends. Support has already gotten back with me far sooner than expected, I sent them the same detailed information and was able to send the video as well, they told me that they think something is wrong with the power supply and are going to replace it. I’m still going to do a stand-alone test run. I haven’t been able to get the loud noise to repeat whether plugged in to the machine or not. The power supply has developed a buzzing noise after the event that was not there before which was in the video I sent them.
What I ended up doing was to replace the internal fan (e.g. not the front fan) with a Noctua NF-A6x15.
As per other posts on here, the wires needed to be swapped, but I did it non destructively: I popped the wires out of the original fan extension cable header (just using some tweezers to push the pin down from the “top” before it slid out the back of the connector).
After consulting the wiring diagram for the fan, blue and green got taped back onto the cable. I then just shoved the black/yellow pins into a 2 pin JST female connector (I made sure black lined up with black, and yellow went where red was from the stock fan’s connector) and hot glued the wires to the connector to keep them from popping out.
Plugging everything back in, and it all worked, except that now my PSU is absolutely silent (it has 2 Noctua fans in it)!
I finally caved and bought the new rails, so my machine will hopefully be completely silent soon.
