Y-Axis: Loud resonance (help needed)  

RE:

Not sure if I'm able to help much given that there's not too much information to go on here, maybe you can upload a video of it :).

some steps I would take are:

1. isolate, make double sure that the sound is the y-axis (maybe it's interplay between 2 different stepper motors? when the print head moves diagonally?)

2. if the sound is 'resonancy' then you can check it by grabbing firmly on the chassis + squeezing and twisting it with your hands to see if that gets rid of the sound, if it does, then there's hope.

3. get a dampener (foam or sponge) and put it under a plate that the printer sits on, I also made myself a concrete slab to further absorb vibrations. This makes a big difference!

4. you can try to loosen / tighten different combinations of screws on the chassis itself, it's what I've done, and it might feel like a bad idea to make parts of the printer looser, but I considered it worth it to get rid of some resonance on my part.

RE: Y-Axis: Loud resonance (help needed)

I was so surprised seeing your reply. I wanted to make this post, so I started typing it...then went to the print, trying to narrow down the noise with different prints I prepared for that issue and film it. Things didn't work as planned....I couldn't find a consistent pattern....so I thought I never sent this post :-D. I really don't know why I still send it - I never would make such an "empty & open question". So sorry - but at the same time so grateful to still see such a comprehend and friendly reply. I saved your answer and I am sure it'll help me to narrow things down.

But if an admin sees that, don't hesitate to delete my post. I didn't plan to post that 90% unfinished. 

I would never end a question without any "thank you" note or proper friendly ending.

Thanks again & best wishes,

Constantin