Public Service Announcement: Tune Your Belts Today!
I have discovered that with daily use, the belts on the Core One can get out of tune pretty quickly, especially in the first weeks of operation.
Of late, I have taken to a regular weekly maintenance that includes belt re-tuning: I can occasionally see belts that have slipped by as much as 10MHz. In my application, this will show up first as slight irregularity on parts printed on some areas of the build plate, and if left uncorrected, can lead to VFA.
As a reminder - belt tuning can be found under the Settings menu : Settings -> Manual Belt Tuning.
Best Answer by Protoncek:
...the belts on the Core One can get out of tune pretty quickly, especially in the first weeks of operation.
That's very normal. I always wondered why Prusa doesn't point that out more in their manuals, even it's very important? All new things must "set-in" and belts are no exception. Checking and re-tunning belts after a couple of week after purchase should be made mandatory and specialy pointed out in printer's manual.
4 Prusa Core One + (formerly MK4S w/ MMU3, MK4 / MMU3, MK3S+/MMU2, MINI+), Octoprint, ASA, PETG, PVB, (some) PLA.
RE: Public Service Announcement: Tune Your Belts Today!
Haven’t touched my belts in months and printing very well.
RE: Public Service Announcement: Tune Your Belts Today!
My belts changed a bit over the first few weeks, but are very stable now. I check them weekly because I'm OCD, but they rarely need adjustment. I've never been able to get them tight enough to resonate at 10 MHz. 😆
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My belts are getting tighter but my wife says I just need to cut back on carbs. The other belts I check once a week.
RE:
...the belts on the Core One can get out of tune pretty quickly, especially in the first weeks of operation.
That's very normal. I always wondered why Prusa doesn't point that out more in their manuals, even it's very important? All new things must "set-in" and belts are no exception. Checking and re-tunning belts after a couple of week after purchase should be made mandatory and specialy pointed out in printer's manual.
RE: Public Service Announcement: Tune Your Belts Today!
Bambu Lab even check the belt tension before every print by default, with a very brief accelerometer measurement. (The printer remembers the most recent resonance frequency, so it does not need to do a full scan.) It helps that they have the accelerometer built into the print head as a standard feature...
I also like Bambu's way of setting the belt tension. The tensioners are spring-loaded to automatically provide the correct tension, and then clamped in place by two screws to ensure that there is no flex under load. So "adjusting the belt tension" just means loosening two pairs of screws, moving the print head back & forth by hand to let things equilibrate, and re-tightening the screws. I wonder why Prusa did not implement it in this way -- are there any downsides?
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It helps that they have the accelerometer built into the print head as a standard feature...
Yeah, well... some of Prusa's decisions aren't quite clear... one of them is why a 10-15$ worth of accelerometer is NOT installed into printhead by default, but we must buy it separately...
other thing i just resent them is if i buy kit version of Core1 then it seems 1100€ is not enough to enclose 1kg of filament (worth in the range of 5€ or less for prusa), but only 10g (or so)... sorry to say, but shame on them..
and so on... but, still, overall i like it, it prints very well and i'd buy it again without thinking twice. What i love (among otheres) is adaptability: loads of custom parts, things... to alter, add, improve...
RE: Public Service Announcement: Tune Your Belts Today!
other thing i just resent them is if i buy kit version of Core1 then it seems 1100€ is not enough to enclose 1kg of filament (worth in the range of 5€ or less for prusa), but only 10g (or so)... sorry to say, but shame on them..
Except then people would complain they're being forced to buy filament of the wrong kind or... and it would push postage even higher... and if you've just bought a 1000 monies printer you're probably going to buy a lot more filament really soon anyway.
RE: Public Service Announcement: Tune Your Belts Today!
Except then people would complain they're being forced to buy filament of the wrong kind or... and it would push postage even higher... and if you've just bought a 1000 monies printer you're probably going to buy a lot more filament really soon anyway.
None of these arguments have prevented Prusa from including a free roll of filament with the assembled printer though. Which makes kit buyers feel like "second class citizens" in a way... But hey, we got a set of semi-decent tools instead!
RE: Public Service Announcement: Tune Your Belts Today!
But then there was the Black Friday sale that included the camera, advanced filtration unit, the "+" upgrade when it came out, and a roll of filament, for free. One could argue that there are better cameras and better filters, but in hindsight it was a pretty good deal.
RE: Public Service Announcement: Tune Your Belts Today!
Except then people would complain they're being forced to buy filament of the wrong kind or
It's not about right or wrong filament, it's that you assemble the printer and then you can't do anything with it until you buy some filaments... not even test it. And, sith 10+ kilos of printer one roll of filament won't increase postage...
as said: we get a feeling that we're a second class buyers, just because we like to assemble and know how it's made...
RE: Public Service Announcement: Tune Your Belts Today!
If you start building the printer at the same time you place an Amazon order, chances are you'll have a truck load of filament on your doorstep before you finish the thing. Also, I like Prusament filament a lot, but $30+ for 1 kg of PET-G doesn't compare well to $25 for 2 kg of PET-G on Amazon (Elegoo). Shipping raises the price to crazy from Prusa, but with a Prime membership on Amazon, it's free.
RE: Public Service Announcement: Tune Your Belts Today!
Yoi just don't get it...
it's like... say you buy a car at your dealers but you don't get a single liter (or gallon) of gasoline inside, so first thing you must do is to walk to a petrol station and buy some to be able to drive home...😭
RE: Public Service Announcement: Tune Your Belts Today!
The first thing I did when I opened my Core One upgrade kit was to throw away the PLA samples. Given it was an upgrade kit, I already had a ton of filament lying around. If it's a full kit, then yeah, they should throw in a spool of filament at least.
RE: Public Service Announcement: Tune Your Belts Today!
ok, if nothing else there's no need for 1kg spools, small one (200 or 300g?) would do.
If we go forward: when i bought MMU3: a nice thing would be to enclose 5 samples. Again, small spools would do...
RE: Public Service Announcement: Tune Your Belts Today!
And my indx should arrive with 8 kilos of prusament! (Not)
Anyway, prusament is just too nice to actually use. My samples (from mini+ kit and core one kit) are still sealed in their bags. 🤪
Back on topic, tensioned my core one on first build, again when the belt tuning strobe firmware was released, and recently before redoing the accelerometer tuning with the recent firmware. Was never far off "correct" and didn't notice any change in print quality.
RE: Public Service Announcement: Tune Your Belts Today!
Was never far off "correct" and didn't notice any change in print quality.
Same here. I do re-calibration every now and then (with auto belt tuner and also that with accelerometer), but so far i didn't see any print degradation or improvement after re-calibration.
RE: Public Service Announcement: Tune Your Belts Today!
For me, I only do functional prints and I didn't notice the VFA's until everyone was talking about them, then you can't "unsee" them. So I got into a phase of checking belt tension before each print. Now I don't bother. I check about once a week or so but not religiously.
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I gotten belt tension now right but my printer is creating layer shifts....
I contacted the support and they said one motor was failing on my 2 weeks old machine, did the replacement, first few prints worked fine-ish then now reappeared. Checked belt tension they are perfect.
The layer shifts were constant before into a specific direction and after change it went into the other direction....
RE: Public Service Announcement: Tune Your Belts Today!
I contacted the support and they said one motor was failing on my 2 weeks old machine, did the replacement, first few prints worked fine-ish then now reappeared. Checked belt tension they are perfect.
The layer shifts were constant before into a specific direction and after change it went into the other direction....
Another popular cause is that a pulley which is not properly secured on the motor shaft. It's worth checking the two grub screws on either side. Do you have a factory-assembled printer or a kit?
Assuming that the shift occurs in a 45° direction, which corresponds to movement of one motor only, the displacement direction you observe will tell you which of the two drive trains has a problem.
Also, collisions of the nozzle with the printed object may cause displacements. Do you notice any lifting corners where the print detaches from the bed, or excess filament (blobs) on the top layers?