Completely new so this may be nothing, but reading about the issues with the z when the 6 first shipped, I at least wanted to ask.
If I am using job controls in cura and I run my z to near the top (10 at a time) I hear no noise other than standard printer noise.
However when I run it from the top (not dead into the stops top) down I hear loud whining from the right z rod.
Its about in the spool area z height wise, so say it starts more or less at the top of the spool and continues down about 3/4 of the way through the spool and quiets down the rest of the way to the bed.
Is this supposed to happen? And is there a write up on a fix if its an adjustment error?
I’d need to see a video to tell you for sure. Louder noise at higher speeds isn’t unheard of, and can be a few things, either ignorance or something you will want to fix. You can try applying white lithium grease to the leadscrew itself (and only the leadscrew, never lubricate the bearing rod’s, you’ll gum them up) which may improve things. Also you can pull it and check for debris in the threads. It’s possible you have a loose bolt that is vibrating harmonically and causing problems it could also be a failing 608 bearing or a loose motor coupler, though that would be unusual on a new printer.
It could also be an alignment issue. That would be a bit more serious.
This might not be your issue but worth checking.
I had my left lead screw sagging a bit which caused a rattling noise when driving the Z-axis quickly. If I tried to wiggle the right hand side screw, it did not budge. The left hand screw wobbled side to side about a millimeter. All I had to do was to unscrew the green part that is pushing the lead screw upwards and re-tighten it while pushing the lead screw upwards towards the bearing in the top plate. Now it barely wobbles if I wiggle it by hand and the rattling noise is gone.
Thanks for the explanation and nice pictures, that solved my problem! Just like you showed, for me the left side leadscrew (near the control box) was making a ton of noise when starting a new print. Your pictures showed the process pretty well, but removing the control box was actually a bit harder than I thought it would be since its hard to access the two lowest screws. I found tipping the entire printer on its side (on the control box) gave me the access I needed to remove the control box. With the control box removed, doing the adjustment you described was fairly easy, and the noise level now is reduced greatly. I may try a small bit of white lithium grease on the threads too.