Wavy mystery, unacceptable quality
Hello, I got my kit a week ago and built the printer over the weekend. However, the surface quality is sub-optimal and not normal, as I've been told. There are waves. I'll add some pictures to show the issue:
The first print looked comical even, compared to my old Ender 3 V2. The spacing of the pattern is 2mm, which leads me to believe the issue has something to do with the motion system (belts?). I have so far:
- recalibrated belt tension, input shaping and phase stepping
- set speeds to use only the official presets, structural and balanced
- tried gyroid, cubic and grid infill
- loosened gantry on both sides and retightened
- reset the printer and redone calibrations, without calibrating for input shaping or phase stepping
- tightened belts, loosened belts, tightened belts...
- loosened linear rail and retightened
- removed extruder gears, reinstalled and recalibrated extruder
- talked with support
The quality with structural profile is barely acceptable. I thought these steps had fixed the issue and tried reprinting my part using balanced preset. The print started to look wavy again so I stopped it. Interestingly, the rear left corner had a few layers where the waves did not appear:
But that is the only wave free section I've gotten from this printer. Support asked me to print a cube, well I printed this thing:
It seems to me that sections printed slower have less waviness going on. The printer also has some massive resonance. I linked this video to support chat too, but they didn't say a word about it. Is it normal?
If you have any suggestion, please do share them.
RE:
This is way more as it should be. I would start over. First of All, restore factor, settings. Repaet the complete check of the motion System. Start wirh checking if xy is square and all build correct together ( loosen the belt tensioners for the Check, Look if there ore gaps on one side when you move the Gantry complete to the Front. If all fine, tightwn the belts, doch the belt Tenside Procedere wirh the App. Check for All screws tound about the motion System and the extruder. By the way - the Sound when you move it, is not normal.
RE: Wavy mystery, unacceptable quality
I strongly recommend you disable the motors before you manually move the parts!
RE: Wavy mystery, unacceptable quality
This is way more as it should be. I would start over. First of All, restore factor, settings. Repaet the complete check of the motion System. Start wirh checking if xy is square and all build correct together ( loosen the belt tensioners for the Check, Look if there ore gaps on one side when you move the Gantry complete to the Front. If all fine, tightwn the belts, doch the belt Tenside Procedere wirh the App. Check for All screws tound about the motion System and the extruder. By the way - the Sound when you move it, is not normal.
Support chat already told me to do those things and they had no effect. I have checked the screws too, nothing is loose.
I strongly recommend you disable the motors before you manually move the parts!
The motors were disabled. It happens when the printer is turned off too.
I printed one of those VFA tests, and it seems they come back around 200mm/s. That's where the BALANCED profile sets the outer perimeter speed, very nice. I have now started printing parts with 175mm/s perimeters and 65mm/s outer perimeters. The quality is slightly better, but I still find it worse than expected.
RE: Wavy mystery, unacceptable quality
Somethings seems off in the hardware, like already pointed out. Ive never seen anything like that, even before all the late "fixes", only very faint pattern at some speeds
RE: Wavy mystery, unacceptable quality
My checklist would be:
squared gentry
belt properly tuned (using the latest sw)
print with the "balanced" profile
Movement shouldn't create such noise but, on the other hand, it should be done with the motors disabled.
If the noise still happens, I'd check the bearings and also if the belts are properly routed and the pulleys mounted right.
RE: Wavy mystery, unacceptable quality
Having listened to the vibration noises in the video, I would suspect some loose screws. (On top of potential belt tension issues; but I would check the general assembly first.)
But this thread has become a bit of a one-sided conversation. It would be good to hear back from the OP before we dump even more advice on them. 😉
RE: Wavy mystery, unacceptable quality
Having listened to the vibration noises in the video, I would suspect some loose screws. (On top of potential belt tension issues; but I would check the general assembly first.)
But this thread has become a bit of a one-sided conversation. It would be good to hear back from the OP before we dump even more advice on them. 😉
Hell yeah that's what I'm thinking too, too bad the messages I send are waiting for moderation. Perhaps that will go away as my account gets older? I am grateful for any ideas however, don't hold back just because it takes to hear from me!
Anyway, I checked the screws, and nothing is loose as far as I can tell. Belt tension is good too and there's nothing apparent that could be wrong. All calibrations have been run multiple times and the printer has been reset as instructed by support. I am a mechanical engineer after all, this shouldn't be as big of an issue as it has become.
Now I'm probably starting to overthink this. The belts on the left side of the extruder are aligned, and not on the right side. I checked the XY carriage model and it seems the pulleys are mounted 13,5mm apart. With a tooth pitch of 2mm there shouldn't be any resonance regardless of the belt mounting position, right? Can anyone with a known good core one check if the teeth on the belts are aligned or not? Makes no difference? How about the motor side of things? Would skipping a few teeth on one of the motor pulleys align it any better? Or perhaps I set belts too tight while assembling the printer and the free length on the sides has hit some magical resonant frequency, because the belt tensioners have a ton of room for adjustability? The artifacts I see are spaced 2mm apart, which leads me to believe it has something to do with the belts or their mounting. Or it is something else entirely that just amplifies the effect. I have no clue.
RE: Wavy mystery, unacceptable quality
One more hint- check the stepper mounts. Since this is an very deep Vibration, could be an loose stepper to - and this can cause your printing issue too.
RE: Wavy mystery, unacceptable quality
But this thread has become a bit of a one-sided conversation. It would be good to hear back from the OP before we dump even more advice on them. 😉
I like threads where the OP disappears and then there are 20 pages of speculation. 🧐
RE: Wavy mystery, unacceptable quality
better than the OP asking multiple questions and nobody answering 😀 😀
But this thread has become a bit of a one-sided conversation. It would be good to hear back from the OP before we dump even more advice on them. 😉
I like threads where the OP disappears and then there are 20 pages of speculation. 🧐
RE: Wavy mystery, unacceptable quality
This is probably going to look like spam to you once the messages are approved, but trust me time has passed on my end. I wish my messages got through quicker.
I triple checked the motors are tightly mounted. I fear I would strip the threads if I tightened any more. Yet still, there is that sound. I believe it is the "x-motor". I used the manual belt tuning to reach a particularly bad resonance and demostrate the source of the sound on this video:
NOTE: I AM NOT SUGGESTING MY BELTS ARE TUNED TO 77.5 HZ! ONLY USED FOR PURPOSES OF SHOWING THE MOTOR ISSUE! DO NOT TELL ME TO TIGHTEN THE BELTS!
Now I'm sending the video to support to see if they think there is an issue. Anyone else have similar experience?
RE:
Now I'm sending the video to support to see if they think there is an issue. Anyone else have similar experience?
First time I've seen (or in this case heard) this issue. Best recourse is to contact support. Maybe a bad motor?
RE: Wavy mystery, unacceptable quality
How ist about the Pulley on the Motor? Did you checked this ? And yes support would bei an good idea
RE: Wavy mystery, unacceptable quality
I think it was in a parallel thread where you had already confirmed that for diagonal movements, only one direction causes the resonances. So something related to one of the motors, or the neighborhood of one of the motors, seems like a plausible culprit.
Have you checked the screws which hold the mounting blocks for the left Y rail (and in particular the rear left one) as well? Or could it just be a panel in the vicinity which resonates? Touching various components while you are pushing the print head, to see whether you can quench the noise, is the best way to try and isolate the source in my experience. Maybe find a second pair of hands to help!
RE: Wavy mystery, unacceptable quality
Now I'm sending the video to support to see if they think there is an issue. Anyone else have similar experience?
First time I've seen (or in this case heard) this issue. Best recourse is to contact support. Maybe a bad motor?
I contacted support and they suggested my motor is installed wonky. Picture of wonky install below:
According to support "the motor is almost certainly fine". They suggest I swap the motors and see if the sound follows the motor. And while this sounds like they are avoiding sending replacements, I can see the idea. Also for some reason they asked me to count the teeth on the pulley. Do they send pulleys with different amounts??
RE: Wavy mystery, unacceptable quality
Oh, and the "waiting for moderation" is hopefully a thing of the past, or will be very soon. You need a certain number of posts (is it 5 or 10?) until you are trusted to post without adult supervision. 😉 I still recall from my start here on the forum that it was quite frustrating not to be able to participate in a discussion in real time.
RE: Wavy mystery, unacceptable quality
Just so you don't feel lonely, I have the exact same print problem. I've done the same things with no good results. Two things I noticed when my prints were OK'ish was the bottom belt was way downs on Hz's to the point of not registering in the app. Well that was a no go at 92 Hz's the print was worse than your print. I'm in the process of trying a fix for the second thing, it's just a stab in the dark, but you never know. An idler pulley with a smooth surface, one with the belt teeth running over it to the print head, I'm waiting on a new toothed one to arrive. Never know your luck in a big city they say, even though I don't have high hopes, I will post back after testing.
RE:
I don't know why Awaiting Moderation but it wouldn't allow me to post this pic in previous post.
Well here is my print with belts at correct tension (by the app).
I could use it as a back scratcher, just apply stick.
RE: Wavy mystery, unacceptable quality
Strange to see this a second time within a few days, after 7 months of Core One kits where I don't recall seeing this issue. I am wondering whether maybe Prusa has opened a new batch of pulleys which includes some bad specimens, where the teeth don't properly mesh with the belt teeth?
@tazaparts -- sounds like Prusa is considering a similar idea, wrong number of teeth on pulley? In your printer, it would probably only be the X motor or pulley which has a problem. If you have the time, swapping the motors incl. pulleys, testing, then swapping only the pulleys back, testing again, would tell the full story.
The motor and its mount look fine to me in your picture. Did you send the photo to Prusa support as well?
The whole "try this, photograph that" dance with Prusa's support team can feel a bit like they are trying to play for time or fob you off. But in a situation where neither you nor support have enough information to pinpoint the problem, I think it is a fair ask. It's different when you are convinced that you know the issue and just need spare part XYZ, but they make you jump through all kinds of hoops -- I have been through that and found it pretty annoying.