Retracting and Clicking  

RE: Retracting and Clicking

Newish owner of a Prusa Mini here.  I have the clicking on retraction too, but my prints are great quality, so for me, the retraction click wasn't/isn't impacting print quality. I have taken apart my extruder and inspected the gearing, and on my Mini, this is definitely the cause of the click noise.  There is slop between the gears that I cannot really entirely eliminate, but I did manage to reduce the noise significantly by assembling the extruder with force down from top of the inner extruder assembly while screwing the halves together, to mash the gears together a better, and applying a lot of lubricant.  Now it makes a noise, but it's less of a "click", and more of a whirring of gears with a slight click accent noise occasionally.

I think unless you were able to find gears that meshed better, or you were able to alter the way the existing gears interacted with more precision than the current design allows, you might not be able to eliminate the clicking, but I also don't think it's a huge concern other than it being noisy.

RE: Retracting and Clicking

@lienmeat

Post a video and maybe we can help you figure the cause.  

RE: Retracting and Clicking

@cwbullet

It was quieter before, right after I tried to get the gears to mesh better and lubed it up, but after printing for a few hours today, it's about as loud as before.

RE: Retracting and Clicking

@lienmeat

That sounds fairly routine sounds.  Can you post a video of the print head while it is printing?  It is helpful to see what it is doing with the noise.  

RE: Retracting and Clicking

I don't like to revive very old posts, but I had the same issue and fixed it.

I went back to the first video I did of my first print of the whistle that is included on the usb key, and the clicking was there already.

Since there was no problem during prints for me, I reprinted the mini extruder front and rear parts.

The parts that came with the printer were revision F1 (front) and F4 (rear). These parts were uploaded on February 19th 2021 and are labeled R1 (front) and R4 (rear). The screws fit much better into the slots, and the gears have noticeably less room to wiggle. There is still a sound you can here when it retracts, but it is more of a low grinding sound (which I assume is normal). I am also not sure if those printed parts are older or newer, but I would guess they are older.

The only bad thing about this that I noticed, is that the initial pull in of filament is a bit louder, which I can live with.

RE:

Well I just upgraded my mini extruder to the bondtech dual drive (Trianglelab clone) two days ago in hopes to fix this problem but the clicking sound is back after the initial few hours of printing. Baisically the same story as with the original extruder, started to click after first few prints. Print quality is good with both. The clicking sound is not as loud because the big gear is plastic but still annoying.

Seems to me that this clicking problem is a general design flaw of non direct drive extruders (or atleast of the two I have experience with). I guess that after the initial break-in of the extruder, a small gap develops between the gears that produces the clicking on extruder retractions and decelerations/pauses. Is the gap due to gear wear or is the motor slowly pushed away by extrusion forces/vibrations I dont know, only a tiny gap is needed to produce the clicking sound.

RE:

That backspin is absolutely normal on Bowden tubes, the effective retraction is 5 to 10 times more than a direct drive. The clicking shouldn’t probably be there.

 I’m waiting for mine delivery and I will tell you how it sound.