geekhack
geekhack Projects => Making Stuff Together! => Topic started by: dagdrivaren on Wed, 22 January 2014, 04:19:45
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I'm thinking about ways to quiet down my keyboard (the one in the signature) and I figured I'd try out putting o-rings on the switches. But I've read that some have put a dampening mat inside the case and are pleased with the result. So I figured I'd ask which one would be best and how much room there is inside the keyboard case? What have you tried and how much of a difference did it do?
As far as I can tell (I'm new to the forum as you can see) a pretty popular choice seems to be something called shelf dampener (like the user Pacifist did here (http://geekhack.org/index.php?topic=52677.0), for instance). Though I feel like it should be easy to find I actually can't seem to find such a mat (I live in Sweden). As I'm not sure what it's called in swedish I may be using the wrong words when I google it. All I can find is some variation of the type of drawer mat that for instance IKEA has (http://www.ikea.com/us/en/catalog/products/10109491/).
I did get that one of those and put it inside the case, though I'm not sure it made much of a difference really. That's why I'm considering alternatives. The obvious place to look seems to me to be a noise dampening mat especially made for computers. Presumably they are pretty good at dampening noise as they are especially made for that purpose. Here are a couple of pretty slim ones I'm considering: Akasa Paxmate (http://www.akasa.com.tw/update.php?tpl=product/product.detail.tpl&no=181&type=Accessories&type_sub=Acoustic%20Silence%20Kits&model=AK-PAX-1) and Silverstones SF01 (http://www.silverstonetek.com/product.php?pid=270&area=en). They are both 4 mm thick.
So I thought I'd see if anyone has any thougts on this. When I've seen people making this type of modification I've never seen anyone use that type of dampening mat so I'm wondering if there's a good reason for it? Do you think the 4 mm is too thick to fit inside a Filco Majestouch case, maybe? Is the reason people use the ordinary shelf dampening mat that they dampen the noise about the same, and the shelf mat is simply cheaper?
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That drawer liner from Ikea is exactly what a lot of people use, mainly because it's so cheap and easy to find and because it compresses pretty well. I don't know anyone who has used computer case dampening, but it should work. You could also pick up a cork mat which will work for dampening as would something like a neoprene rubber sheet.
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the best surface dampener you can buy is sorbothane, which is a very very soft polyurethane. you only need a little bit at keyboard keypress weights, so cost will be comparable to neoprene and other rubbers. one thing to watch out for is dynamat and dynamat like rubber/tar compounds. they are effective in that they're dense and heavy and lower the resonant frequency of a part by quite a bit BUT they smell like crap and the smell takes about a thousand years to go away. you can get sorbothane on amazon for pretty darn reasonable prices, or mcmaster. the prices between the two vendors are very comparable -- almost always within a few bucks. however, there is only one manufacturer of sorbothane, and they don't have a heck of a lot of resellers, so just find a thin sheet that fits your keyboard case and go with that -- load ratings are all listed on the sorbothane manufacturer's site: aptly located at http://www.sorbothane.com/ ;). you want to hit load rating as exactly as possible. if the sorbothane is too stiff, it will transmit vibration, and if it's too soft, it will also transmit vibration. ideally you get a good squish on the sorbothane between the two surfaces. that's generally how you know that you've hit your load rating.
as for user experiences, i've used this stuff in all kinds of crazy places -- under 600W woofers, under a 1hp air compressor, inside the frame of the makerbot, and it's just a miracle material: ridiculously effective at dampening vibrations and stopping them from propagating
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the best surface dampener you can buy is sorbothane, which is a very very soft polyurethane. you only need a little bit at keyboard keypress weights, so cost will be comparable to neoprene and other rubbers. one thing to watch out for is dynamat and dynamat like rubber/tar compounds. they are effective in that they're dense and heavy and lower the resonant frequency of a part by quite a bit BUT they smell like crap and the smell takes about a thousand years to go away. you can get sorbothane on amazon for pretty darn reasonable prices, or mcmaster. the prices between the two vendors are very comparable -- almost always within a few bucks. however, there is only one manufacturer of sorbothane, and they don't have a heck of a lot of resellers, so just find a thin sheet that fits your keyboard case and go with that -- load ratings are all listed on the sorbothane manufacturer's site: aptly located at http://www.sorbothane.com/ ;). you want to hit load rating as exactly as possible. if the sorbothane is too stiff, it will transmit vibration, and if it's too soft, it will also transmit vibration. ideally you get a good squish on the sorbothane between the two surfaces. that's generally how you know that you've hit your load rating.
as for user experiences, i've used this stuff in all kinds of crazy places -- under 600W woofers, under a 1hp air compressor, inside the frame of the makerbot, and it's just a miracle material: ridiculously effective at dampening vibrations and stopping them from propagating
would it be possible/worthwhile to use sorbothane to dampen switches individually??
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yah, i don't see why not. i would use the little stick on bumpon versions that are self-adhesive and put one under each switch on the bottom side of the PCB
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yah, i don't see why not. i would use the little stick on bumpon versions that are self-adhesive and put one under each switch on the bottom side of the PCB
I was thinking more like using it as a replacement for o-rings or landing pads... 8)
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sorbothane the company does make gaskets, but i don't think if they get that small. now i'm curious though.. what the typical ID, OD of an o-ring for switch dampening?
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sorbothane the company does make gaskets, but i don't think if they get that small. now i'm curious though.. what the typical ID, OD of an o-ring for switch dampening?
I'm thinking typical is something like 3/16" ID, 5/16" OD, 1/16" Width
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nubbinator:
That drawer liner from Ikea is exactly what a lot of people use, mainly because it's so cheap and easy to find and because it compresses pretty well.
I'm not going to argue with you on this one, you probably know alot more about this than I do, but during the few months I've spent reading GeekHack and Deskthority I've come across a bunch of people putting a dampening mat inside their keyboard cases and every single one has used that type of mat I linked to above. And that mat is not the IKEA mat (at least not the one they're selling here.
Cork mat, what? Really? :D Thanks for the suggestion about neoprene too. I'm completely clueless about this stuff.
mkawa, thanks alot for your comment! Again, I haven't got a clue about different types of rubber and so I've pretty much used any. Given how useful it can be, all this stuff is interesting. As for the specific suggestion of Sorbothane, I'm not sure it's possible to get a hold of it here in Sweden and I'm not sure I want to spend that kind of money on shipping one across half the world. But even if I don't, I still found it very interesting and something to keep in mind for other uses at the least. I'm afraid I don't quite understand what you mean by"you only need a little bit at keyboard keypress weights...". Also, if it's so important to get the load rating (load rating = roughly stiffness of the rubber, yes?) right, how would I know what to get?
Actually, after reading your comment and skimming their site, I'm curious about this stuff. A shame I probably can't get a hold of it here (I'll look around).
Thanks for the help all!
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large sorbothane mat can get heavy. sorbothane is available on amazon though. ezpz to the EU.
i just put in an RFQ for surobothane o-rings. actually sounds pretty promising.
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i just put in an RFQ for surobothane o-rings. actually sounds pretty promising.
coming soon to geekhackers store?
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i just put in an RFQ for surobothane o-rings. actually sounds pretty promising.
coming soon to geekhackers store?
Interesting..
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I just used this (http://www.target.com/p/basic-grip-shelf-liner-white-12x5/-/A-11172319). My keyboard isn't a subwoofer or an air compressor.
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i just put in an RFQ for surobothane o-rings. actually sounds pretty promising.
coming soon to geekhackers store?
no idea
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I'm really curious about those o-rings as well.
mkawa, could you answer the questions above regarding Sorbothane , perhaps?
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sorbothane is practically a gel. it's the softest polyurethane i know of, and is generally found in shore duro A30-70. A30 is basically jelly, while A65 is fairly firm. that said, the shore durometer rating understates how soft sorbothane it. sorbothane has very very high yield strength (ie, excellent memory), meaning that it can deform a very large amount before it degrades and holds the deformed shape.
practically, what this means is that it is very good at isolating high amplitude vibration. the energy of the compressive waves is dissipated into the sorbothane. the way to think about it is that the vibrations are potential energy propagating through some solids. when they hit the sorbothane, the potential energy of the wave is converted to mechanical energy which is limited to non-permanently deforming the sorbothane.
typically, the other way to dampen the vibration of, say, a panel of bulk material is to make it heavier by eg attaching an asphalt/rubber composite to the panel. this lowers the resonant frequency of the bulk material to frequencies low enough that they do not propagate, or are eg inaudible. dynamat, etc. are all formulated for this purpose.
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Thanks alot for the clarification, rellay appreciate it!
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warning about asphalt-based mats: they smell like asphalt. seriously. they will smell like crap for months before they finish offgassing.
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I'll make sure to stay away from such mats, then. I'm still leaning towards some of the noise dampening mats I mentioned earlier. I am relly curious about Sorbothane, though. Could you briefly mention a few times you've used it, perhaps? It seems a bit complicated in the sense that it is quite important to get the exactly right one for the specific situation.
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I am relly curious about Sorbothane, though. Could you briefly mention a few times you've used it, perhaps?
as for user experiences, i've used this stuff in all kinds of crazy places -- under 600W woofers, under a 1hp air compressor, inside the frame of the makerbot, and it's just a miracle material: ridiculously effective at dampening vibrations and stopping them from propagating
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the engineers at sorbothane are much better at calculating optimal material specification for your application, but the "get some squish" rule is what i go by as a rule of thumb. if you have too much squish in your sorbothane then you're going to damage it and you need more sorbothane. too much squish is when it becomes very rigid and is obviously acting that way. too little squish is simple: if you don't see it bulging at all, you have too much sorbothane and not enough load.
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Oh, I misread. I thought he was mentioning the most "crazy uses" he's seen or heard of. The intention of the question was to get examples of more regular and standard uses, to get some ideas as I don't really have any experience with these types of materials.
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I bought 4 of these (http://www.ebay.com/itm/250989166427?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649). So we'll see when they arrive.
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I bought 4 of these (http://www.ebay.com/itm/250989166427?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649). So we'll see when they arrive.
Interesting. What are you planning on using them for? It would be nice if you would share your thoughts on them when they arrive.
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that's basically what i use under my caseless quickfire xt. i cut some small sections of sorbathane off, hot glued them on, and then stuck bumpons onto the sorbothane liberally. i have a much larger number of similar squares dampening the 3d printer.
one correction though, the listing labels the sheets as 50D. 50D is like a hard hat. sorbothane sits squarely in the OO regions of the shore durometer scale.
here's a nice rule of thumb to use for shore duro ratings: https://docs.google.com/viewer?url=http%3A%2F%2Fwww.smooth-on.com%2Fpdf%2Fdurometer_with_logo.pdf
sorbothane occupies the region between 30 OO and 70 OO.
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for those of you that use drawer liners, how many layers do you use? I believe someone from another thread said he put four rows of different number of layers, as in top quarter, upper middle quarter, lower middle quarter, and lower quarter.
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for those of you that use drawer liners, how many layers do you use? I believe someone from another thread said he put four rows of different number of layers, as in top quarter, upper middle quarter, lower middle quarter, and lower quarter.
I used one. And I put it between the PCB and case.
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I bought 4 of these (http://www.ebay.com/itm/250989166427?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649). So we'll see when they arrive.
Interesting. What are you planning on using them for? It would be nice if you would share your thoughts on them when they arrive.
I got them last week and put them inside my Leopold. 3 mats is just barely enough for that.
Tomorrow is going to be a long day of typing so i will let you know after that. :)
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Wonderful! I await your comment with interest.
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Wonderful! I await your comment with interest.
Fohat.digs is selling some sorbothane in the classifieds. I just bought some.
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Thanks for mentioning that, but I think I remember reading somewhere that one has to have 60 coments on the forum in order to participate in the classifieds section, no? (Can't seem to find it at the moment, though.)
*edit* Oh, I misunderstood. YOU NEED AT LEAST 60 POSTS TO POST NEW TOPICS IN CLASSIFIEDS & GROUP BUYS
. Great!
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Right, you can still buy stuff if you have less than 60 posts. Just can't make a "WTS Thread" yet.
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Wonderful! I await your comment with interest.
Fohat.digs is selling some sorbothane in the classifieds. I just bought some.
My sale is not for sorbothane mats, which is a gel-like material, as I understand it.
What I have is a very firm, thick, dense rubber mat very much like the material of an inner tube, but several times as thick.
Also, this is intended as a mat for the keyboard to sit on, it is probably not appropriate for the inside of the case.
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Wonderful! I await your comment with interest.
Fohat.digs is selling some sorbothane in the classifieds. I just bought some.
My sale is not for sorbothane mats, which is a gel-like material, as I understand it.
What I have is a very firm, thick, dense rubber mat very much like the material of an inner tube, but several times as thick.
I was about to mention the same.
https://en.wikipedia.org/wiki/Sorbothane
https://en.wikipedia.org/wiki/EPDM_rubber
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Thanks for clarifying that.
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Sorry about that! I remembered incorrectly!
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Sorbothane looks like great material, but seems extremely expensive for use as a mat.
A quick look made it seem that $40 at best might get you a 12" square, which could be cut and spliced to make something approximating the right size for a keyboard.
If you could get a roll that was at least 6" wide, or a sheet that was well over a foot in at least one dimension, it might be more appropriate.
If you are looking to put smaller pieces on the inside, then those little squares might be better. The 4" squares would be perfect to set small speakers on, however!
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sorbothane is not expensive if you remember that thin is often better than thick, and then buy large sheets. mcmaster has pretty competitive pricing, and you can get a 24x24x1/8" mat from them for 70$. that's enough for a very large number of keyboards. i bought a 24x24x3/16" mat about a year ago and even after pulling 2sqft for the damping system in the 3d printer and cutting off little and big isolating pads for a ton of stuff, i have a good 10x12" left.
another mold-type which might work extremely well for keyboards is the strips (with or without PSA). they have molds for up to 6" wide strips that you can basically buy per foot.