Rattling noise on MK2 when bed is moving  

Re: Rattling noise on MK2 when bed is moving

Most likely bearing issue.
Check if Y frame is perfectly perpendicular. Steel rods must be parallel, they must keep the same distance in front and back. Their distance should be 170mm (center to center). The frame must not be twisted, so if you look at Y rods from side, they must be parallel as well. If everything is done OK and there is still that rattling sound, it is faulty linear bearing. Maybe it is damaged only partially. You can check that by turning the bearings 90 degrees along their axis. Turn them gently and carefully while moving them forward and backward, don't turn them on the spot. Do it one by one and check if the sound disappears.

Re: Rattling noise on MK2 when bed is moving

Are you running in (HighPower) mode? That can be noisy. Does your printbed still make a noise when (SilientMode) is set?

Re: Rattling noise on MK2 when bed is moving

I cant tell by the video but to me that is the fan blowing air and it is bouncing off the holes not being bridged. Took me ages to figure out what it was on mine. I changed to Igus bearings but still the same thing. Have since changed back to the standards as I did not like the Igus. But yes if the fan (fan on the front) is running then its the noise from the air hitting the parts.

If the fan is on too high this is when you can get thermal overrun protection because the air bounces back and cools the nozzle. 😉

Re: Rattling noise on MK2 when bed is moving

Thank you

In the video the printer is printing in silent mode.

I've measured the Y frame and i seems to be exact 170mm between the center of the rods, both in the front and back.

Its not the fan because i can also hear the sound when printing the first layer without fan, although the sound is not that high.

Re: Rattling noise on MK2 when bed is moving

Hi
I have had same problem, mine was caused by a broken bearing, on the Y axis the single linear bearing, when I removed the rail a load of ball bearings came out..
I have replaced them with a better bearing all 3 . And it's a lot better,
Steve

Re: Rattling noise on MK2 when bed is moving

Mine had this LOUD noise the very first time it moved. Straight out of the box, I have not idea how to fix it but it's so loud it wakes everybody in the whole house Not a good thing from Prusa Research. They need to give us a fix for it.

Re: Rattling noise on MK2 when bed is moving

Same problem here. I am 99% sure it's a bearing problem. The reality is that the bearings included with Prusa printers seem to be of questionable quality. Not so bad that it affects the prints, but certainly bad enough that it causes a lot of noise for many people. I had the same problem with mine, and I isolated the problem to be the bearing. I am planning on just replacing the bearings with much higher quality bearings, but I may be going a bit overkill since the bearings I'm going to test are probably 20x more expensive.

Re: Rattling noise on MK2 when bed is moving

I have this too, where can good quality bearings be bought that will work with the mk2?

Re: Rattling noise on MK2 when bed is moving

I have this too, where can good quality bearings be bought that will work with the mk2?

That's a good question. A lot of people seem to like the igus DryLin bearings, but they are designed to be compressed in a housing, not attached using zip ties. I myself am currently planning on experimenting with SKF LBBR8-2LS/HV6 bearings, but they are super crazy expensive (normally 25-30USD each - cheapest I found was 19.52USD each from 123bearing.com). They are without any shadow of a doubt, overkill, and add an unnecessary and extraneous cost to a printer that does not need it.

I would love to hear about some good high-quality replacements that do not cost an arm and a leg.

Re: Rattling noise on MK2 when bed is moving

Just finished building my MK2 over the weekend and discovered the same rattling noise. The weakest link in the y-axis assembly, in my opinion, is the way the bearings are simply strapped onto the metal carriage with zip ties. So I ended up unscrewing the heated bed surface, cutting off the zip ties holding the bearings in place, and adding small pieces of felt between the bearings and the carriage before reassembling everything. That eliminated the rattling.

Re: Rattling noise on MK2 when bed is moving

juat rebuilt a lot on my printer (adding lots of variables for rattling). i actually found the source of all my loud loud rattling.... the threaded rod tops of the z axis. they arent the straightest rods that came with my kit bht they work, however, they will touch the sides of the hole on the z top plate causing a major amount of noise. i was running a test print after my rebuild and i was going nuts trying to find it. i put my fingers on the z top to keep the rod away from the hole side and boom, my major noise was gone. im curious to see if anyone else here can try that and see if its the cause.

Re: Rattling noise on MK2 when bed is moving

Have the same Z axis noise. Is there a possibility to reduce it?

Re: Rattling noise on MK2 when bed is moving

honestly i have no idea, but im into it. i think im going to try this:

http://www.thingiverse.com/thing:1322407

if you find a cure let me know!

Re: Rattling noise on MK2 when bed is moving

I have same issue also, doesn't seem to affect printing, but I would like to fix it.
I did see this in the assembly instructions:
http://manual.prusa3d.com/Guide/4.+Z-axis+assembly/106#s1600

But not sure what it means by" release the motor holder at the bottom and slightly move it."

Re: Rattling noise on MK2 when bed is moving

yeah im not sure about that either. in my case i do have a slightly bent rod so it will never be able to not touch the printed part. prusa sent both of them that way. but my prints are still good but it has been the major cause for a lot pf my noise/rattling.

worst csse scenario is i print new tops but drill the threaded hole way bigger in an attempt to not have it touch. that might be a quick fix, not tested though!

Re: Rattling noise on MK2 when bed is moving

another thing to check is how tight the y belt is and hpw tight the bearings are. i know people may have a tendancy to over tighten fearing things are too loose byt things can be too tight as well. the bearings if they are the regular lm8uus can warp if a zio tie is too tight or if you are using a mod to screw them into place. that can cause bearing damsge that can make a rattle too.

jist a thoight.

Re: Rattling noise on MK2 when bed is moving

hello,
Hello, I understood why there is a strange sound.
Because look at our table. As it is tightened.
There goes a nut and a washer that is adjacent to the bed. Think faster, the nut is badly tightened and the sound is transmitted throughout the bed. we have them 6 pieces . They all look tightened but at in certain resonance (i dont say faster or slower print speed) the whole table starts to make vibro-sound.
So these washers must have another anti-vibration washer that touches the bed.
we never touch this nuts because they already assembled on the bed, we just screw bolts through the black y carriage .

please comment !

Re: Rattling noise on MK2 when bed is moving

Is this still an on going issue with the MK2S? Just curious to know so that I can upgrade before assembling my kit. Doing research before my MK2S arrives end of the month.

Re: Rattling noise on MK2 when bed is moving

Have the same Z axis noise. Is there a possibility to reduce it?

... its amazing sometimes how the simplest detail can make all the difference. i double/triple checked everything, rebuilt over and over etc.

do this to straighten them:

printer is built, have the x axis about half way up.

confirm that your threaded z rods are not in the center or near center of the hole in the z axis top stop as possible. (again if they are rubbing the sides this will cause vibrations etc. during z axis moves)

simply loosen (do not remove) the two screws holding the z trapazoidal nut to the z bearing holders. (typically, the black screw nut with 2 screws).

simply shift/slide the nut slightly until the z threaded rod is as close to the center of the hole on the z axis top stop parts.

tighten screws with correct alignment found.

test by simply using the lcd to move the z axis up and down. if there are more wobbles, repeat the proccess until the desired placement is found.

i hope this helps anyone thinking its bemt rods etc. it may simply be the slight placement of the trapazoidal nut.

thanks for reading!

Derrick