I was reading about the A1 and problems with bed-slingers printing tall models because the moving bed tends to make the model wobble and layers can shift or the model gets knocked down.
That got me to thinking about core xy and tall model problems. Most of the problems that I have seen are caused by using infill that overlaps and when the model is tall the nozzle hits the infill bump and knocks it loose.
Now to the point about anti-vibration feet and tall models. Anti vibration feet do not stop the printer from vibrating. In fact, they let it vibrate more. Their purpose is to isolate the printer vibration from the surface that it is sitting on.
Depending on how soft the anti-vibration feet are they could allow the printer to vibrate enough to make a tall model wobble and have the print fail just like a bed-slinger. The perfect solution would be to bolt the printer to a large block of granite so that it is so solid that vibration is at the minimum possible.
My table has a pretty light plate an I noticed the ams lite shaking quite a lot sometimes.
I’m currently in my first prints and had a couple of days of problems and I guess I solved it and the issue maybe was that I had a heavy 10m ruler hanging on the desk which sometimes did swing a bit. (still running hypothesis…)
Just now I had ordered somen thick rubber mats for my washing machines and as soon as the A1 finishrs printing the ams top mount I want to try if that might helps further.
I think if the vibration from the printer transfers to something like a fully loaded ams lite and that one reduces it’s weight during printing that might can throw off the calibration and cause problems.
My prints have been usable but with very ugly edges I was about to throw out the 3rd party filament but re-calibrated this morning and now it has been printing pretty flawless for hours… (also saw that measure tape swinging and removed that…)
Alll in all pretty terrible first 3d printing experience but now mostly due to me not knowing the root cause 100%)
There’s another issue no one seems to think about.
When we perform vibration calibration (klipper or Bambu, same principle) we measure vibrations of ONE component: the toolhead. This assumes the printer (and the bed, which doesn’t wobble at all by itself, inside the printer) is static, so any vibration measured at the toolhead is the relative vibration between toolhead and printed part/bed.
Now we introduce any mean for allowing wobble of the printer as a whole. The most effective seem to be the HULA feet.
We are now breaking the rules of the game: if the printer (and bed) wobble as a whole, what we measure at the toolhead will be the sum of relative vibrations/resonances between toolhead and printed part (what we want to reduce, the ringing) PLUS the wobbling/resonances of the printer movement as a whole.
When is this relevant? it depends. A printer on a garden tile which is isolated from the desk/rack via foam will allow really little wobbling, so the resonance frequency will be likely higher than what the printer measures/cares about (150 Hz).
A printer on HULA feet will be (basically) completely free to wobble, since the damping is minimal and the friction has been reduced with bearings. It is very likely that the lack of stiffness of the “joint” between printer and base (so, the feet) combined with the reduced mass of the system (the printer alone!) will result in resonant frequencies within the range which can affect ringing in the printed parts.
Basically the calibration tries to cancel out two types of vibrations at the same time and the result is either a wrong resonance frequency (and ringing therefore reappears) or it will use a “broader” input shaping algorithm which will cause more smoothing of the sharp corners.
The reappearance of ringing matches the experience of people with HULA feet, and that’s why (I mean, no one thought about it, but this is the explanation why) it’s recommended to calibrate without HULA feet.
As someone already wrote, all this kind of damping feet/surfaces make sense only to reduce noise. With a foam+tile the print quality won’t be affected measurably, with the most advanced noise reduction feet noise will decrease more, but quality too (unless they are removed for calibration…).
Hmm, I’m not an ME, but I think a bunch of the tuning it is to cancel resonance, not vibration. Wouldn’t those resonances still exist if the printer was entirely free-floating?
Sure but there are now also resonances of the printer wobbling as a whole, in addition to resonances of the tool head. The former however don’t affect print quality.
It may seem counterintuitive to use feet that allow the printer to wobble, but it probably serves a purpose. Like shocks on a car it dampens and smooths out sudden movements, which leads to reduced wear on gears and belts. We had a large format (60" wide) HP inkjet printer at work that wobbled quite a bit on the stand as the printhead would traverse back and forth rapidly. I asked the technician about that and he said it was by design; The sudden acceleration and decelerations are rough on belts and gears and the wobble dampens the constant shock. The printer was designed to compensate for the known and consistent vibration. He said the machine should be on a level, solid surface that doesn’t wobble, but the “internal” wobble was necessary and by design to improve printing quality and extend the life of the printer. I wonder if that same thing applies to using the vibration feet on the Bambu printers.
As long as it’s a flat and stable surface, you can probably place it on your toilet seat…or your floor. Just make sure you won’t kick it either by error or… with intent to kill.
Vibration wise, the floor is a good option.
Not a good place regarding back-pain though.
And the z-belt is open below the printer, able to collect dirt swept under the printer.
Thank you for your amazing insights @julie777
And thanks to all members who pitched in with all kinds of interesting information and experiences.
My approach is from a different perspective: maximum print quality possible.
I don’t care about noise (there are much noisier things around in the shop, believe me), and it kind of bothers me if the printer is shaking all around (though I can live with that if that’s the path to max print quality).
I currently have my P1S on a table that sits under a shelf. It occurred to me to also lock the printer from above, so I places two beams of wood at the top left and right edges, pressed against the shelf above, squishing almost all give from the antivibration feet. The printer is very stable, almost no visible shake. But I can’t tell if that has increased print quality, as I always print at a think layer and medium to slow speeds.
My idea for a custom table/shelf for the printer (soon to have a second one) is:
Surface measurements: 120cm (48") width by 60cm (24") depth (for two printers)
4x4 columns at all 4 corners, acting as shelf structure, strongly fixed to floor and ceiling
25mm thick shelves with 2x2 beams.
Concrete slabs on the shelf, and printer on top of the slabs. Maybe 1" or 2" thick slabs.
Shelf above printer (10 cm from it) also with slabs on it for weight.
Parallel beams pressing between against the underside of the top shelf and top left and right edges of printer, to bear it down well enough.
AMS on top of top shelf.
It will be almost as if I snugged the printer in between walls of concrete, allowing near zero structural movement.
Does that sound valid or lunacy to you?
Thank you for your input.
Ps: If any of you would be trolling my crazy ideas, please make it fun and smart. Nothing like a clever takedown to make one rethink one’s priorities.
Thread took a bit of reading, but well worthwhile. Was looking at so many “novelty” solutions, conical sleeves, thrust gearings, even a solution using a cradle of linear rails in the X and Y planes.
My printers are on a fairly ridged kichen base cabinet, which sit directly on the floor, not on legs, which is stuffed full of mainly books and reams of a4 paper and card, the tops are 48mm laminated worktops.
So after all that head scratching, im picking 400x400x32mm 17.5 kg each to put 2 under each printer, then a 400x400x10mm EVA foam floor mat.
Thus is way the cheapest and easy option and sounds like the way to go.
As my noise seems to be exacerbated by the echo effect of the cabinets, as that there are no feet, so cabinet carcase sits directly onto a laminate floor thats on a chipboard floor on the first floor bedroom im using as printer/computer room
It should be interesting as the A1 much louder than the A1 mini.
So I went ahead and setup my 3 x1s on 16" pavers like you suggested, with cut foam mats underneath. I really liked the idea of somehow locking the printer to the paver, but seemed nuts to try to rig up a bolting set up.
Instead, I modeled and printed some snug-fitting rigid feet from pla, set them into the printer with strong doublestick and epoxied the bottoms to the pavers.
I figured this would be better than the stock rubber feet as they seemed pretty squishy to me.
So, just wanted to share the option for those wanting to attach the printer to the paver. I haven’t calibrated and run it yet, waiting for the epoxy to dry!
So far so good, meaning all prints so far look really nice. I haven’t printed anything really tall and thin yet which is where I had issues when using the anti-vibration feet.
Also, it’s easy to slide the machines on the foam pads if I need to move a little bit so that’s nice.
I am wondering if I ever need to remove the printer from the slab I will need to lift it off of the feet, and then re-align them to get it back on. This may be challenging, though can’t say for sure as I haven’t tried. But I think it’ll be workable.
