I have seen so many posts here and on Reddit about printer vibration and asking the question “should I buy the anti-vibration feet?”.
From my background in engineering, as a machinist, and an amateur audiophile, I thought that I would provide some detailed information so that users can understand what is really going on and make the choice that works for them.
Purpose
The purpose of anti-vibration feet is to reduce the vibrations transmitted to the surroundings. They are commonly (and more properly) called isolation feet or pads, because they isolate the machine’s vibrations from the surroundings. If you have ever seen a portable generator run you know that the feet are not stopping it from vibrating. 
Isolation pads are usually made of some kind of elastomer that is flexible enough to allow the machine to move independently of the surface that it sits on. In shops with large machinery this can be extremely important as a large machine can shake the entire building without them. Another common use is under speakers when trying to isolate speaker vibrations from other audio equipment. Generators, power transformers, air conditioner compressors almost always have isolation pads.
For a 3D printer the pads can help make your desk more usable while printing if the printer is sitting on it.
If you have two printers sitting on the same surface the isolation can help prevent one printer from affecting the other as much.
However, even with the isolation you probably do not have your printer sitting on anything heavy enough to stop it from moving. It does not matter if you have isolation feet or not when the table is light weight and rocks easily, the isolation really will not work. (3D printers are not large machines sitting on a concrete floor.) BBL printers so fast and are so jerky, they are still going to cause the table or other stand to shake, even with the feet.
Printer Vibration
If the goal is to stop the printer from vibrating because the vibrations are affecting the print, then anti-vibration feet are not likely to help. In fact they actually allow the printer frame to move more because it is sitting on something flexible. If you commonly have problems with tall prints it could be because your printer is just moving too much.
There are some forum posts on the right track to reducing the actual vibration (shaking) of the printer. However, I think they combine both isolation and reducing vibrations and do not explain which solution works for which problem.
I want to discuss several solutions for reducing printer vibration (and ignore isolation).
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Slow it down.
The easiest and most effective way to reduce the printer vibration is to slow it down. This is even more applicable to the jerk settings (how fast it accelerates and decelerates) than raw speed. Every time the print head assembly changes velocity there is an opposite reaction in the frame of the printer. The harder the tool head pushes the more the frame moves. If you are having a problem with a specific print you can either tune the various speed and acceleration settings, or you can try just changing to silent mode. -
Add Mass
More mass moves less for a given amount of force. If the printer frame weighed 10 tons then the tool head jerking would still require the frame to absorb the same amount of energy, but the frame would not move noticeably. So, to prevent the printer from moving/vibrating as much you could bolt it to a concrete slab, such as the floor of the garage. It would move much less. This is not a very good solution. And it would not even completely fix the problem because the printer is not made of stiff enough material to prevent flexing. You could bolt it to a concrete block and set a large concrete block on the top of the frame and the solid coupling would effectively raise the mass of the printer and significantly reduce any vibration. -
Set the printer on a more stable surface.
A more reasonable solution and one that many posts get partially right, is to set the printer on an object with a high mass.The typical post says: put the printer on a concrete paver on a neoprene pad on your desk.
I want to break this down, because that solution is mixing isolation and vibration reduction without explaining the benefits and drawbacks, or separating out each part.
The neoprene pad between the concrete paver and the desk is acting as an isolation pad so that movement of the paver will cause less desk motion that otherwise would happen. This is good if you are trying to keep the desk from moving.
Setting the printer on the concrete paver without any flexible isolation between is trying to make the mass of the paver part of the mass of the printer. This helps reduce the amount of printer shaking. (It is very convenient that Home Depots sells 16" square concrete pavers for a few dollars and they are just the right size for the printer.) Because the stock printer feet are fairly hard,the coupling is reasonably solid. Bolting the printer frame to the paver would be even better at providing what would be effectively a single object with high mass. I do not know of anyone that has gone that far.
So, in summary, cheap concrete pavers with your printer setting directly on them is the best easy and economical solution to reduce printer vibration. One is good, but more is better. Do not put isolation pads/feet between the printer and the pavers.
My Current Solution
I modified a combination of #2 and #3 for my printer. I had an old high end audio rack which has pointed feet that go right through the carpet and into the sub-floor. (Audiophiles do this to provide a solid foundation for their equipment. The also often use mass by making turntable bases out of granite and such.) Now I have the stand solidly connection to the frame of the house. The rack is very short and as inflexible as possible. I filled the bottom shelf with concrete pavers and put more on the top shelf under the printer. It is not as solid as a boulder, but it does not move much and not easily. My printer sits directly on the top paver.
I have my Prusa on an ELFA drawer unit. It works just fine. Putting the P1P on one had it moving about six inches side to side.
I started with the P1P on an old dresser and it printed fine, even though the entire dresser was moving around. The engineers at BBL did a great job compensating for vibration. I just wanted to try to fix the occasion problems with tall prints and not have to watch it shake so much.
My new setup has very little motion. In addition, some of the problems with printing tall thin objects, or strange surface artifacts are gone.
Note: when you make a change like this be sure to run the full printer setup calibration. The printer resonance frequencies will change significantly.
The Solution will continue to change
After trying one paver, which worked well, I went to buy more pavers and bought the wrong ones. My bottom shelf currently has 12" ones. I plan to get more of the 16" squares.
The other issue is that my printer is really too low. My long term plan is to build a cabinet with drawers to both store supplies and to set the printers on. I will build the cabinet extra stiff to help eliminate flexing. I am going to leave a spot under the bottom drawer for a stack of pavers, and I am going to provide an inset into the top so the printer is sitting on pavers as well. I expect the cabinet ready to use will have a footprint slightly larger than the base of the printer, but will have a working weight of about 250#.
I will add more info as my printer station changes.
Aside:
You can skip this because I am just ranting about a pet peeve which is triggered by reading anything about reducing vibrations.
BBL calls them anti-vibration feet. This is great, and sort of correct.
But, most of the posts in forums and even ads from companies who make such items call them "vibration dampeners", which is false.
1. dampen means "to make slightly wet", such as dampen a cloth to wipe up a spill. (It can also have the emotional meaning such as "that dampened our spirits")
2. damp (as a verb) means to reduce oscillation or vibration. We put sound damping in a room to improve the acoustics. A car has a damper (shock absorber) along with a spring so the uneven road does not cause it to bounce up and down forever. The damper, damps the oscillation and causes the bouncing to quickly stop.
Sorry, I just had to put that out there because I see it so much. Almost every listing on Amazon for sound deadening material also calls it sound dampener. Grrr. :wink:
Or that I would have worked in the field since then.
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): As long as the feet are not fully squashed but have some way to go, their spring constant is likely still in the linear range. So they should still be effective in the same frequency range.
Just put “River table” in the youtube search bar 
This could be entirely and absolutely wrong! 
My wife has a few stories about my “smart” reasoning 
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