RE: Prusa CORE One kit assembly instructions
I think I've fixed it, ridiculously simple if it turn out to be a permanent fix...I've done about 5/6 prints and the z noise is gone, it was making noise every time a print finished until now.
I'm hesitant to post the solution as I thought I fixed it before but it returned 😂
Have you tried a Z calibration, which drives the bed all the way down to the base? (Control > Calibration & Test > Z alignment calibration) If it remains quiet near the bottom, please do tell us what you did to silence the drive! 🙂
RE: Prusa CORE One kit assembly instructions
All that was required (on my machine) was simply tightening up the screws on the trapezoidal nuts. I think from my paranoia about over tightening things as I was building the kit, that resulted in me under tightening certain things... I should point out I have in no way overtightened them now, maybe a quarter turn more on each screw and the noise has completely gone. Im pretty confident this is the cause.
I had a quick look at the assembly guide and there is no warning about over tightening them initially...obviously don't over tighten anything, but they need to be tight.
RE: Prusa CORE One kit assembly instructions
I think I've fixed it, ridiculously simple if it turn out to be a permanent fix...I've done about 5/6 prints and the z noise is gone, it was making noise every time a print finished until now.
I'm hesitant to post the solution as I thought I fixed it before but it returned 😂
Have you tried a Z calibration, which drives the bed all the way down to the base? (Control > Calibration & Test > Z alignment calibration) If it remains quiet near the bottom, please do tell us what you did to silence the drive! 🙂
I haven't but I'll give that a try when I get the chance a bit later.
RE: Prusa CORE One kit assembly instructions
All that was required (on my machine) was simply tightening up the screws on the trapezoidal nuts.
Maybe "squeezing" the POM a bit helps to take some minimal play out of the nut/lead screw combination, and hence stops the lead screw from vibrating laterally? As long as there is not too much friction, resulting in lost steps or blockage, that seems like an acceptable solution.
(I had been wondering whether my diligent approach of re-seating the nuts after the smooth rods were inserted, avoiding lateral tension on the nuts and lead screws, might actually have promoted the vibrations.)
RE: Prusa CORE One kit assembly instructions
In my kit, it was most notable in the XY motor mounts (steps 5.17 and 5.19 of the build instructions; the M3x30 screws which serve as axles for the dual idlers). I think others mentioned some different parts in their kits.
Those holes appear to be 3.2mm in diameter, and given that I always use 3.3mm for (snug) M3 clearance holes in my models it's not surprising that they don't bite very much.
I've 'sleeved' the holes at the far end down to 3.1mm, just as an experiment - see the red parts in the image - and am printing a sample in ABS with the 0.2mm SPEED profile.
But I would agree, since there's no axial load, even a slight bite should be fine, so not worth reprinting.
RE: Prusa CORE One kit assembly instructions
I think I've fixed it, ridiculously simple if it turn out to be a permanent fix...I've done about 5/6 prints and the z noise is gone, it was making noise every time a print finished until now.
I'm hesitant to post the solution as I thought I fixed it before but it returned 😂
Have you tried a Z calibration, which drives the bed all the way down to the base? (Control > Calibration & Test > Z alignment calibration) If it remains quiet near the bottom, please do tell us what you did to silence the drive! 🙂
When the Z goes right to the bottom I get a bit of a rattling noise, completely different to the previous groaning Chewbacca noise.
I can live with that 😂...I very rarely print anything even close to that size.
RE:
My apologies - the hole itself is 2.9mm. It has a tear-drop top section (a characteristic of Prusa's modelled holes to make sure they print cleanly), for which I needed a fraction over 3.2mm to capture it all. 2.9mm is a lot better than 3.2mm!
So my 0.1mm smaller sleeve is 2.8mm.
In my kit, it was most notable in the XY motor mounts (steps 5.17 and 5.19 of the build instructions; the M3x30 screws which serve as axles for the dual idlers). I think others mentioned some different parts in their kits.
Those holes appear to be 3.2mm in diameter, and given that I always use 3.3mm for (snug) M3 clearance holes in my models it's not surprising that they don't bite very much.
I've 'sleeved' the holes at the far end down to 3.1mm, just as an experiment - see the red parts in the image - and am printing a sample in ABS with the 0.2mm SPEED profile.
But I would agree, since there's no axial load, even a slight bite should be fine, so not worth reprinting.
RE: Prusa CORE One kit assembly instructions
I have plenty of Prusa orange ASA, so I'm tempted to reprint the PETG parts, especially the black parts, partly because I've never been a fan of black parts (very difficult to work on except in good light) and partly just 'to make it my own'.
This is all the parts in the petg-parts-black.3mf file, reprinted in ASA. And I've just discovered that my printer kit was shipped with only one of the orange side handles, so I may as well the three parts in petg-parts-orange.3mf as well, to match.
RE: Prusa CORE One kit assembly instructions
So based on the comments from Jan, do you still intend to use the ASA parts for the motor mounts and cable clip?
RE: Prusa CORE One kit assembly instructions
So based on the comments from Jan, do you still intend to use the ASA parts for the motor mounts and cable clip?
Yeah, good question - I had the same thought when I saw Jan's reply. The ASA motor mounts seem to have a bit of flex - not as much as PETG, but not super rigid. I'll try them I think, and can always do them again in Prusament orange PETG if necessary. The ASA cable clip opens far enough to get the cable in.
RE: Prusa CORE One kit assembly instructions
Chris, let me know how it goes with the ASA parts. ASA seems to have many of the same properties for flex as PETG so you might be good. I was thinking plain PC but even that seems a bit stiff for these.
So based on the comments from Jan, do you still intend to use the ASA parts for the motor mounts and cable clip?
Yeah, good question - I had the same thought when I saw Jan's reply. The ASA motor mounts seem to have a bit of flex - not as much as PETG, but not super rigid. I'll try them I think, and can always do them again in Prusament orange PETG if necessary. The ASA cable clip opens far enough to get the cable in.
RE: Prusa CORE One kit assembly instructions
Will do. Unfortunately I won't get to build my kit until after Easter - it arrived just a couple of days too late for me to build it before, with work and personal commitments. But at least it's given me time to print my own 'anything-but-black' parts.
RE: Prusa CORE One kit assembly instructions
I will start with one point that surprises me a little: the Y bearings are already embedded in an injected plastic part.
Does that mean MK4S upgrade kit will not reuse original bearings? Or the injected parts will be replaced by printed one?The bearings in question:
Do you have any new info? I'm interested in this, there is no printed part and if it is pressed, maybe it can be disassembled and the bearing replaced, I have mixed feelings about it 🙁
RE: Prusa CORE One kit assembly instructions
ASA scheint viele der gleichen Flexibilitätseigenschaften wie PETG zu haben, also könntest du damit gut zurechtkommen. I
I have printed the holders for the Y-axis rods on the MK4S from PCCF. As well as the Finda clamp of the MMU3.
Both break before they give way.
But both work perfectly with ASA.
RE: Prusa CORE One kit assembly instructions
I really do like this Orange - comes out so nice when printed.
I have plenty of Prusa orange ASA, so I'm tempted to reprint the PETG parts, especially the black parts, partly because I've never been a fan of black parts (very difficult to work on except in good light) and partly just 'to make it my own'.
This is all the parts in the petg-parts-black.3mf file, reprinted in ASA. And I've just discovered that my printer kit was shipped with only one of the orange side handles, so I may as well the three parts in petg-parts-orange.3mf as well, to match.
RE:
I will start with one point that surprises me a little: the Y bearings are already embedded in an injected plastic part.
Does that mean MK4S upgrade kit will not reuse original bearings? Or the injected parts will be replaced by printed one?The bearings in question:
Do you have any new info? I'm interested in this, there is no printed part and if it is pressed, maybe it can be disassembled and the bearing replaced, I have mixed feelings about it 🙁
In theory you can change it, I mean, I did it to Misumi one when I tried to get read of resonance noises.
I wouldn’t recommend it as I needed a lot of force to remove them as they are press fit in the sockets.
I used a vise, a « pin » and rubber hammer to get them out. When reinserting new bearing you have to really pay attention on the orientation of the lines of balls inside bearings. Check first the original orientation as it’s hard to explain (when you have the mounted bearing in the final orientation balls should draw a X and not a + if you look through the bearings).
Risks of deterioration of the bearings is quite high when removing or replacing it.
PS: it did not work, I didn’t manage to improve noise, so I replaced the original bearings after all.
RE: Prusa CORE One kit assembly instructions
I will start with one point that surprises me a little: the Y bearings are already embedded in an injected plastic part.
Does that mean MK4S upgrade kit will not reuse original bearings? Or the injected parts will be replaced by printed one?The bearings in question:
Do you have any new info? I'm interested in this, there is no printed part and if it is pressed, maybe it can be disassembled and the bearing replaced, I have mixed feelings about it 🙁
In theory you can change it, I mean, I did it to Misumi one when I tried to get read of resonance noises.
I wouldn’t recommend it as I needed a lot of force to remove them as they are press fit in the sockets.
I used a vise, a « pin » and rubber hammer to get them out. When reinserting new bearing you have to really pay attention on the orientation of the lines of balls inside bearings. Check first the original orientation as it’s hard to explain (when you have the mounted bearing in the final orientation balls should draw a X and not a + if you look through the bearings).Risks of deterioration of the bearings is quite high when removing or replacing it.
PS: it did not work, I didn’t manage to improve noise, so I replaced the original bearings after all.
I'm waiting for a rebuild kit and have new bearings ready so I'm asking 🙂 a colleague recommended MYT bearings and they are very good and I can recommend: https://levendigs.com/products/myt-linear-bearing-kit-for-prusa-mk4?_pos=4&_sid=2f0ccb5d5&_ss=r
I'm curious how the bearing will be in the rebuild kit maybe Průša packed us a rubber hammer and a vice 😀
Translated with DeepL https://www.deepl.com/app/?utm_source=android&utm_medium=app&utm_campaign=share-translation
RE: Prusa CORE One kit assembly instructions
Anyone know if the timeout can be adjusted for the LEDs dimming? I like the fact they dim, but would like them to stay on full brightness for longer.
Also I can find the option to disable the Chewbacca noise when the Z drops at the end of a print 😂
To fix the groaning Z drive, it will probably be sufficient to lubricate the lead screws. The POM trapezoidal nuts should be designed to run dry, but many users have reported in the meantime that lubrication was necessary to avoid the noise, or even the Z drive getting stuck sporadically.
You may also want to ensure that the lead screws and the smooth rods agree upon where they want to push the heatbed laterally: Drive the heatbed all the way down, loosen the 2 screws at each of the three black trapezoidal nuts on the lead screws to let them all "settle" to the correct lateral position (determined by the smooth rods). Then gradually tighten all six screws. Do not overtighten them; you don't want to distort the nuts.
I am not aware of a way to adjust the light dimming timeout. But maybe there is an undocumented G-code for this, similar to M84 for setting the motor hold current timeout?
So the more technical Prusa support have responded, and their solution is what you said:
"The issue appears to be with the trap nuts experiencing some resistance. Try loosening them slightly and then re-tightening to ensure even tension. Applying a small amount of lubrication may also help improve their movement."
I'll leave mine (for now) as it's not making noise at the moment, but the second it returns I'll be lubricating them.
Am I right in thinking theres some tool I can print for the application of grease , or am I thinking of something else?
RE: Prusa CORE One kit assembly instructions
I used polyether to lubricate the lead screw.
I use Variolube to lubricate the chain on my mountain bike.
The chain stays very clean with the best lubrication.
What has proven itself there can't be bad for 3D printers 😆
I'm not convinced by grease as a lubricant in this area as I think it attracts dirt.
I would put some thin oil on the top of the trapezoidal nut and move the Z-axis up and down several times. Less is sometimes more.
Another thing I have noticed is that the cable tie of the housing fan thermistor can shudder on the belt.
After I tried to optimize the alignment of the belt on the idler pulleys, a behavior occurred on the X axle that I have already read about here in the forum.
When the axle is moved, there is always an increase in resistance and then it slides a little normally again.
This is repeated over the entire length of the X axle.
This behavior occurred after I moved the pulley of the left motor slightly upwards
After I moved it back a little, the axle ran smoothly again.
RE:
I use Variolube to lubricate the chain on my mountain bike.
Haha, I use Muc-Off on my bike, smells nicely of bananas !..really good stuff.