Vibrations when descending Z axis before printing  

RE:

I did the MK4 upgrade and experience this type on noise on all three axis.  I  was able to dampen, not eliminate, the y-axis and x-axis by making the belts supper tight, but I worry about shortening the motor lifespan. I haven't been able to do much about the z-axis noise which sounds just like noise in you vid.  It is my opinion that the noise is an artifact of the 400 step motors and how they are being operated.  The rotational vibration sound is then amplified through connected plastic structures.  I haven't spent much time with customer support, but if you contact start off with the vid. 

It's possible that they be able to give you advice, is so, please pass that on here.

Good Luck

v

RE: Vibrations when descending Z axis before printing

Thanks for your explanations.

Explanations via chat today :

This is actually normal behaviour since the motors move under current - it should only make this sound when its preparing before a print and later on will be gone in the print

here is no guide for mk4 but this page could still help you to find out where it might come from and make slight adjustments in case its coming from the lcd housing. https://help.prusa3d.com/article/vibration-when-printing-mk3s-mk2-5s_2177

it is not directly coming from the Z axis, it only happens when the Z is moving and it can resonate through the whole printer

Question : Is there an improvement planned in future firmware?

Answer :this is how the printer works and will be hearable before printing. its not a defect and most likely wont go away in future updates

RE:

Interesting, 

It may in fact be the new normal,  but something is definitely different on the MK4. My Mk3's were very quite on all axis.

The vibration is begin generated somewhere, what we are hearing is mainly the amplification of that vibration.  The generation of vibrational noise generally requires moving parts, i. e the motors, pulleys, bearings, belts, or fans. For the X-axis we only have the motors and trapezoidal nuts. 

I feel like Prusa has been rushed to get new products on line to be competitive with new and different methods, and noisy printers is one of the more obvious consequences. The responses you got seem typical of their recent attempts  to downplay our frustrations with these noises and several other annoying MK4 attributes. 

I guess you could just stare at you printer for hours, like I have, and try pull out some Jedi voodoo to fix you own problems. I'm still seeking a solution and will post if I find it. 

RE: Vibrations when descending Z axis before printing

I also just received a new assembled printed with the same noise. This is my first prusa so I guess the grinding noise is normal.

It would be nice if they could fix this. I understand it may be of no harm but it sounds like a cheap printer ready to break.

So far the mk4 has not impressed me over the Bambu X1 serries.

RE: Vibrations when descending Z axis before printing

In my opinion, these sounds are caused by choosing an inappropriate rotation speed of the Z-axis motors, when unfortunately some parts of the printer resonate. Note that these sounds do not occur when moving at a different speed. It would probably be enough to change the movement speed and the problem would be solved, but the developers don't want to do this. The problem is also that if I fix it in the FW, it's of no use to me because I won't upload my FW to the printer without losing the warranty.

RE: Vibrations when descending Z axis before printing

I have the same noise on my MK4.When it levels the bed and when Z moves up and down during printing as the extruder moves from one printed part to the other.This noise really annoys me. But I haven't found a solution for this yet. 🙁

RE: Vibrations when descending Z axis before printing

"This is actually normal behaviour since the motors move under current"
"this is how the printer works and will be hearable before printing"

That's a load of crap if that came from Prusa support. I bought the kit and assembled it last year, this noise never happened until many months later for me. Now it vibrates the whole table it's on.  

RE:

When I built my FYSTEC metal enclosure for my MK4 I noticed an increase in sound like this one. The metal base (or wood in your case) can act like a speaker cone and amplify the sound.   My solution was to slide a 20x20x2” concrete block under the printer.  It’s almost totally silent now.  The mass of the block will damp the vibrations out and make the printer whisper quiet.  

RE: Vibrations when descending Z axis before printing

My new MK4 vibrates in exactly the same way when the Z axis is descending in preparation for a print. I've done a few hobby projects with stepper motors and had the same experience when stepping at low speeds. I believe if the Prusa guys changed the step rate in the next firmware release, this issue would go away.

RE: Vibrations when descending Z axis before printing

same vibrations here ...

RE: Vibrations when descending Z axis before printing

Now i've had my MK4 for a couple of weeks now, I can say that the noise is only coming from the left hand stepper motor. So I'm not so sure that this is a resonance issue any more. The right hand motor is pretty silent.

RE: Vibrations when descending Z axis before printing

Same goes for me. The left one is more noticeable. And while it‘s not too bad it‘s a little annoying. I contacted Prusa support about it and they suggested to loosen the trapezoid nuts on both sides a little bit. That indeed reduced the overall vibration.

RE: Vibrations when descending Z axis before printing

I definitely have to look into getting myself one of these units. My goodness these things are amazing.

RE: Vibrations when descending Z axis before printing

Hi together, I had this same issue. Help desk told me it is normal, but also advised installing the latest firmware. Since installing version 6.1.3 my z-axis is completely silent!