My MK4 is very noisy (vibration) in X-direction for large flat pieces
Dear all,
I have encountered recently high noise during printing in X-direction. The video can be found here:
https://youtube.com/shorts/doJWulTNFiw?feature=share
First it looks like the issue discussed here:
But it is the more the x-axis, not the y-axis and it sounds very different in my opinion.
Any suggestion or ideas of root-cause?
Regards
RE: My MK4 is very noisy (vibration) in X-direction for large flat pieces
I'm not sure if it's exactly the same problem, but I also experienced a seemingly similar "washboard" sound. Most often this is on large or circular prints where the print head is moving quickly.
I noticed my MK4 did this the most when I would use one of the speed input shaping profiles with normal PLA (e.g., Prusament PLA, Polymaker PolyLite PLA, Jessie PLA, or MatterHackers Build Series PLA, or even the structural input shaping profiles on matte PLA filaments (i.e., Polymaker PolyTerra PLA). When I've used "high speed" PLA filaments (i.e., Polymaker PolySonic PLA) I haven't yet encountered this issue.
My personal theory is this issue is under-extrusion caused by the combination of high print speeds and inability for the MK4 hotend to heat standard PLA filaments to an appropriate temp to facilitate such a high flow. This seems to cause weird "ridges" or "waves" to be printed, which build up over several layers and the nozzle strikes at high speeds to generate the "washboard" vibration sounds. When this is happening and you pause the print, try running your finger over the top of the infill and perimeters of the print. Do you feel waves, ridges, or some layer inconsistencies? Also, so you see a pattern of holes or divots on one particular exterior area on your finished print? I noticed some particularly large pattern of holes or divots on large circular prints like pencil cups or plant pots.
To avoid this issue I tend to only use Prusa's SPEED input shaping profiles when printing with high speed PLA/PolySonic PLA, use Prusa's STRUCTURAL input shaping profiles for standard Prusament or PolyLite PLA, and use a modified slowed input shaping or non-IS profile for printing matte/abrasive filaments such as PolyTerra PLA. That said, I'm not exactly sure how to actually fix this issue, just a workaround that has worked for me.
RE: My MK4 is very noisy (vibration) in X-direction for large flat pieces
Hello, thank you for your detailed reply. You are right, the issue mostly results during PLA prints, no PETG. I got in contact with the official support and they claimed, that this might be normal by using the standard "Grid" infill with higher infill-rate. The vibration also occurs in X-axis after testing. The prints went normal, but wavy structure were visible. Reducing the infill to 5%, and the problem almost disappeared. Anyhow there seems to be a contact area between the grid-infills, see picture. 
I also get with my finger above the infills as you described, but wavy surface was barley noticeable.
And you are also right: reducing speed seems to work as well, together by using different infill pattern.
RE: My MK4 is very noisy (vibration) in X-direction for large flat pieces
here is the video for 5% infill compared to the one above