@@Vector3DP Adam I apologise for my previous rant at these posts that are following me across RU-vid, they are scammers trying to get people to connect to their Phishing site, they are all over RU-vid and target random peoples accounts and reply to their comments.
I've always found that dealing with a noise or vibration source by attacking as closely to the source is the most effective. Using the cheap stepper isolators is the single most effective item I've found for the money. True, silent stepper drivers work better, but certainly not cheaper or less time consuming. Changing out a driver board or even motherboard can be time consuming depending on your proficiency with the firmware build. The next most effective thing I've found is by modifying or augmenting the feet of the printer to prevent the vibration from travelling to the bed. A 25mm thick piece of closed-cell packing foam like many 3D printers are shipped with under each foot goes a long way to dampen the tranfer of the vibration. I've even put a small rubber "puck" like you put under furniture feet to spread the weight of the printer over a 50-75mm square of the packing foam. That keeps the foot of the printer from digging a divot into the foam and makes the isolation more effective without making the printer "wiggly." Hope these help, but then they're not directly about the bench.... Great videos, keep it up!!
If you think about it you hit the nail on the head with your analysis. With the dampers it’s a speaker, which you can hear in the room. You can hear it less in other rooms because the vibrations are isolated from the frame and therefore the floor and the rest of the house. My idea for keeping noise down is to slightly adapt your original idea. Just make a platform that goes between the printer and the table top to isolate the printer from the table top. That could be rubber feet, a rubber pad or a block of foam. Look at how musicians isolate their studio monitors
Any form of mechanical fastener when used to attach the top surface to the metal frame will point load and concentrate any vibration to that spot, effectively increasing its energy transmission. I would suggest looking at something like industrial velcro, hook and loop fasteners along full lengths of the top. As there is a natural flex and resistance in the fibres and hooks. Effectively tens of thousands of micro springs that will dampen as well as distribute any vibratory force. You will need to use staples to hold it to the underside of the table top (buy a Milwaukee m12 electric staple gun) and use 3M primer 95 on the metal before applying the velcro and it will stay there forever. Its an adhesion promoter that really works. Another one that's amazing for vibration absorbing is 3M VHB tape, the thick (3mm) clear kind. It's not removable but could form the basis of an isolation plate. I workes within a certain part of the military packaging industry and vibration was a big thing we had to deal With. Also, you have been using metal countersink tools on wood, which is why you have those flat spots. Look up the festool centrotec countersink tool. It's actually conical with a hole in the side. It produces perfectly angled and smooth counter sinks. Use with a depth stop for consistency. Also ensure that you have center support for the plywood in the table, as it will flex over time. Consider moving up to 24mm plywood as well. The extra mass in the material will be benificial. Also look at Finsa Fibreboard as it's available in colours like black, grey, red, yellow, blue and green. Very dense and will last for years. Companies like cworkshop, cutltist will be your best sources of material and cnc saw cut components. Its the secret of many cabinet makers. They can supply anything you need including edge banding.
If you're marketing this bench towards DIY types you may be able to get away with creating a hollow chamber affixed to the bottom of the bed and having the end user purchase and fill that cavity with sand or some other super heavy material that can be acquired locally by the end user at low cost. To really stop vibration in its tracks, you need more mass to sink those vibrations into. There's no way around it.
You could fill the profiles partly (2/3 or so) with Sand to dampen vibrations. Works quite well on my diy-cnc router. Or mount the top rigidly and decouple the whole table from the floor with rubber feets. The mass of the table will help to lower its resonat-frequency. Greetings from Germany 👍
Take a look at how festool is attaching the worktop for its festool mft tables And for antivibration, I'm using rubberpads under the printers, the same type that is used on hvac systems. (rubber pads with some blue stuff between)
Mount an anti-printer the the underside of the worktop. It contains all the same steppers as the printer above it and runs a synchronised code so that it produces exactly opposing motions under the worktop to the ones the printer is making above it. The vibrations from above and below will exactly cancel out, thus eliminating all secondary noise. It will obviously double the direct noise the steppers emit into the air as there are now double the number of them but engineering is all about trade offs.
I made 3d printed 90 degree brackets which I screwed in with wood screws from underneath the bench top, I framed my big L-shaped bench with 2x4's so it also also allowed me to print separate shimmed pieces for the pieces I was screwing to that weren't perfectly flat. Didn't want screws showing from the top, gunk will inevitably settle into the recessed areas.
Composite formed of alternating layers of GFRC and polyurethane rubber with lots of filler to add weight. Gets you mass and damping in one. Will take a while if you wait for each layer to cure between pours so do all the concrete layers at the same time if you have space for the moulds and put them together using rubber pours, with minimum setting time between.
How about cork or beech or something inbetween the frame and the top. I think the top material still can act like a speaker in this case though, so often the best solution is to isolate at the printers contact to the top.
Multiple layers of isolation and damping from feet of printer down to feet of workstation. Rubber under printer feet then concrete slab, then rubber sheet, then worktop floating over frame or clamped hard to it with rigidity enhancement like angle iron attached to its underside, then rubber feet or rubber tiles between workstation and ground.
Having rubber/foam under the worktop may help or even a cut-out area in the worktop you could drop them into. Similar to having an enclosure people adding thick rubber then paving slab, having an area built in as to not add more height to the printer may work
For dampening, you can always try gluing foam or rubber on the under side of the table top in the center. Check out RTOM Moon Gels for drum heads. Not the right product for you but the concept is solid.
Why attach the worktop to the frame at all? Gravity will hold it in place, and no drilling or screwing around will be required. Try various types of rubber, cork, or felt strips or tape between the worktop and the top of the frame.
Hope you are still reading these comments. I strongly suggest you change your entire paradigm of thought. You are thinking of "vibration," and using "loudness" as a metric. This is entirely the wrong approach. Think instead of "coupling vs de-coupling" and and use a combination of metrics - I suggest print ringing, loudness (measured) and frequency. Frequency is probably best measured using an accelerometer and an RPi. There are plenty of established libraries for this including one specially built for Kliper (input shaper). You also seem to be re-inventing the wheel, and I suspect relying on unreliable sources for information - namely the maker community, and the hobby woodworking community. In my experience, both of these communities are pretty clueless on these topics. There are industry wide Best Practices, with cost effective solutions. The maker community seems to think that rigidity is not important to 3d printers, and then produce prints that are covered in artifacts that are the result of harmonic vibrations. A rigid machine coupled to a work table, that is then effectively damped will not only print quietly, but will have minimal artifacts. Damping can be achieved with something as simple as a hollow table top filled with play sand. Hard objects will transmit higher frequencies, soft materials transmit lower frequencies (hence you turning your workbench in a giant speaker). Combining the two will allow rigid coupling while minimizing transmission. There is a reason why the most common solution to vibration is a heavy mass (or plinth) anchored with hard/soft layers to the floor (or whatever), and the device coupled to the mass directly. Sometimes tuned masses are suspended from the plinth. In your case, hanging a 3-5Kg bag of weight (play sand, lead, etc) would probably have helped your speaker table top.
Is your workbench attached to the wall? You can't add much more mass to it than your house. You should attach the top of your printer as well as the base to the workbench after mounting it to your wall.
It isn't, mine is actually on wheels so attaching it to the wall would limit the movement a bit. I'm in rented accommodation so not allow to attach anything to the walls sadly, but it gives me an idea of how walls could be used to help. Thanks.
Great material, i use it for the feet on my mk3s actually and it works well. trouble is that its really expensive, it is here in the UK anyway, don't know where you are, maybe cheaper there.
