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There seems to be general consensus that, among other things, a sturdy table is important for print quality.

Within reason, I don't understand why a wobbly table would be bad. Has anyone done a controlled study/investigation on how wobbliness affects print quality?

Ringing artifacts seem to be what people think platform sturdiness helps with. But the frequencies of these artifacts seem to be broadly in the range of 40-100 Hz. The resonance of a cheap fold-out table is seems much lower than that - perhaps 10 Hz or less. And intuitively, it seems that a 10 Hz resonance would have to be very energetic to significantly affect the motion of the extruder.

YouTube links, written studies, or personal experience welcome!

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  • $\begingroup$ I think your answer could be found here $\endgroup$
    – 0scar
    Jun 9 at 9:05
  • $\begingroup$ Purely anecdotal, but my printer is on a not-so-sturdy table and I've never noticed any problems. $\endgroup$ Jun 9 at 11:36
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    $\begingroup$ Printers usually leave a wavy pattern after turning a right-angle corner. A flimsy table will make this worse, causing its own pattern. A flimsy table will cause you to run slower speeds to compensate. $\endgroup$
    – Perry Webb
    Jun 9 at 12:03
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A clear answer is not available, since no one performed a proper test as of June 2021.

The closest answer I can provide is that damping feet result in a change of vibration behaviour, as discussed in this Klipper issue report. How it's not clear.

I paste some of the findings:

I took several measurements with different configurations and the results are quite surprising IMO. The following graphs show the respective vibration results for (from left to right):

1- The retrofit back to the standard hard rubber feet

2- The printer only standing on the "feet clamps" as shown in the picture above

3- The printer standing on the "feet clamps" but with squash balls inserted

X-Axis

enter image description here

Configuration 2 vs 3: The damping is causing an additional spike at ~76 Hz; Power-Spectral-Density is roughly the same; Overall vibration is a bit lower in the damped version (11.4 % vs 16% @ 3hump_ei) --> Probably due to damping the additional spike; A bit surprisingly the shaper recommendation is identical

Configuration 1 (original feet) drives Power-Spectral-Density from e3 range to e4 range

Configuration 1 brought back a dominant spike at around 75 Hz to 80 Hz (which was surprisingly gone with the printer sitting on the hard and small area of the "feet clamps"

Configuration 1 nearly tripled the spike at 75 Hz to 80 Hz compared to No. 3 (Power-Spectral-Density 12,000 vs 4,200) The spike at around 30 Hz stayed pretty much the same

Y-Axis

enter image description here

The effect on the Y-axis is pretty small

My conclusions

The resonance effects very much depend on the type of feet

For whatever reason every damping in the feet resulted in worse vibration

If you want to know more about it, install Klipper and an ADXL345 accelerometer, make measurements, write a blog post or post here in a new answer.

I may be able to do it within within the year. It's a loose deadline, yes.

I have a printer on a wobbly table, but I haven't performed measurements yet.

I expect it to be better than a stiff table, since part of the energy is dissipated by the table and not by the printer frame (we are not talking about independent feet, but table as a whole), resulting in better quality at high acceleration. Of course if your printer runs at 500-1500 mm/s^2 you won't see anything. If you run at 5000+ mm/s^2, then...

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