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geekhack Community => Other Geeky Stuff => Topic started by: QueenXenon on Tue, 20 August 2013, 09:08:03

Title: The Science of Keyboards
Post by: QueenXenon on Tue, 20 August 2013, 09:08:03
As a polymer chemist I get really excited when people start talking about ABS and PBT, and it made me think, maybe I can make a better key cap material.  After poking around google scholar for a bit I realized I didn't have to limit myself to key caps, I could mess around with whatever switches are made out of. 

Here's my question to you:
What material based property of a keyboard do you think is most in need of improvement?

(I gotta write a proposal, might as well be about something the people want and I care about)
Title: Re: The Science of Keyboards
Post by: badcop on Tue, 20 August 2013, 09:10:47
stop abs from shining  :thumb:
Title: Re: The Science of Keyboards
Post by: Photekq on Tue, 20 August 2013, 09:15:33
The three things I really care about :

-Resistance to shine over time
-Resistance to yellowing over time
-Ability to be doubleshot

Honestly I think soon enough PBT will fill that criteria..
Title: Re: The Science of Keyboards
Post by: SpAmRaY on Tue, 20 August 2013, 09:17:47
stop abs from shining  :thumb:

That's called pbt ;)

But for real, I love doubleshot ABS but know eventually it will get shiny.  :-[
Title: Re: The Science of Keyboards
Post by: TheQsanity on Tue, 20 August 2013, 09:25:13
White key caps to be dirt resistant.
Title: Re: The Science of Keyboards
Post by: badcop on Tue, 20 August 2013, 09:27:38

stop abs from shining  :thumb:

That's called pbt ;)

But for real, I love doubleshot ABS but know eventually it will get shiny.  :-[
Thick DS pbt would solve all of our problems /sigh
Title: Re: The Science of Keyboards
Post by: CPTBadAss on Tue, 20 August 2013, 09:29:08
As others have said, I really like the smooth feeling of ABS but I don't like the shine that can come with the caps. I also like thicker keycaps. And I really like aesthetics: doubleshot caps look really nice, windows are amazing, translucency.

But I think resistance to wear, finish of the cap, and the heft/thickness/weight are the most important things in making a keycap.
Title: Re: The Science of Keyboards
Post by: esoomenona on Tue, 20 August 2013, 09:30:02

stop abs from shining  :thumb:

That's called pbt ;)

But for real, I love doubleshot ABS but know eventually it will get shiny.  :-[
Thick DS pbt would solve all of our problems /sigh

No, because it doesn't feel as good.
Title: Re: The Science of Keyboards
Post by: badcop on Tue, 20 August 2013, 09:34:18


stop abs from shining  :thumb:

That's called pbt ;)

But for real, I love doubleshot ABS but know eventually it will get shiny.  :-[
Thick DS pbt would solve all of our problems /sigh

No, because it doesn't feel as good.

It would solve my problems :P
Title: Re: The Science of Keyboards
Post by: Parak on Tue, 20 August 2013, 09:53:39
Hokai, so, I don't care as much about what keycaps are made of as much as what two surfaces that touch each other during switch sliding action are made out of. Now, it just so happens in the case of my favorite subject (buckling springs) that the keycap often (but not always in the case of two piece ones) is the actual thing that comes in contact with the barrel. In the case of cherry, it's the stem inside the switch instead.

So, either one of the two parts, or both, should be made out of material that does not only have low CoF, but also would not cause premature wear to itself or the other contacting part. Who needs lube if the switch action is already smooth?

Proposal: UHMWPE.
Title: Re: The Science of Keyboards
Post by: HoffmanMyster on Tue, 20 August 2013, 10:05:53
Good to see another chemist around here!  I've got some ideas that I want to try out regarding making my own caps, but I want to do more research before attempting anything.

I look forward to seeing what you do here, and if you ever want to bounce ideas off of someone feel free to contact me.  I'm not specifically a polymer chemist, but I know a bit.  (that's not being cheeky, I don't know a ton.)
Title: Re: The Science of Keyboards
Post by: mkawa on Tue, 20 August 2013, 10:08:04
OOOO!!! another polymer expert for me to pester with constant questions!!! hooray!!
Title: Re: The Science of Keyboards
Post by: CPTBadAss on Tue, 20 August 2013, 10:11:00
Yes because you dont pester enough people with questions mkawa :P
Title: Re: The Science of Keyboards
Post by: mkawa on Tue, 20 August 2013, 10:15:56
:D
Title: Re: The Science of Keyboards
Post by: tp4tissue on Tue, 20 August 2013, 10:36:24
How do we make meth into keycap shape..

Then we can sell large quantities as collectables, while charging the Meth price...

and the Authorities wouldn't know any better  :D
Title: Re: The Science of Keyboards
Post by: SpAmRaY on Tue, 20 August 2013, 10:43:13
How do we make meth into keycap shape..

Then we can sell large quantities as collectables, while charging the Meth price...

and the Authorities wouldn't know any better  :D

[attachimg=1]
Title: Re: The Science of Keyboards
Post by: jdcarpe on Tue, 20 August 2013, 10:45:32
Thick doubleshot ABS is fine with me. I don't really care if they get shiny. So keycaps aren't really a big concern to me.

What is a concern is the stem of the Cherry MX switch. If we could analyze the stems from a vintage black switch to find the chemical composition and identify what type of polymer resin they were originally molded from, maybe we could create a mold and make our own stems from the same material.
Title: Re: The Science of Keyboards
Post by: Dubsgalore on Tue, 20 August 2013, 11:46:30
Thick ABS is perfect for me as we'll. Geekhack seems to circulate preference, so everyone has their preferences but many of the members who has tried different sets and materials, prefer thick ABS. For me, all my favorite sets visually are thick ABS, they feel amazing (the best IMO), and they come straight off vintage keyboards, which means there is fun into the hunt for rare sets. Some people are bothered by the shine, but I don't care much. Shine to me means that they have use, and are worn and broken in. Yellowing does bother me, but that can be fixed and removed. It's just perfect for me.

It's great to see someone who is experience and has the resources to experiment with new materials!
Title: Re: The Science of Keyboards
Post by: esoomenona on Tue, 20 August 2013, 11:49:12
What is a concern is the stem of the Cherry MX switch. If we could analyze the stems from a vintage black switch to find the chemical composition and identify what type of polymer resin they were originally molded from, maybe we could create a mold and make our own stems from the same material.

VINTAGE!? Cherry, Y U DO DIS?
Title: Re: The Science of Keyboards
Post by: Quardah on Tue, 20 August 2013, 12:53:25
As a polymer chemist I get really excited when people start talking about ABS and PBT, and it made me think, maybe I can make a better key cap material.  After poking around google scholar for a bit I realized I didn't have to limit myself to key caps, I could mess around with whatever switches are made out of. 

Here's my question to you:
What material based property of a keyboard do you think is most in need of improvement?

(I gotta write a proposal, might as well be about something the people want and I care about)

Keycaps made out of [TITANSTEEL].

http://www.wowhead.com/item=37663/titansteel-bar Fairly easy to craft.
Title: Re: The Science of Keyboards
Post by: JPG on Tue, 20 August 2013, 12:56:39
For keycaps, if you could find a way to take something like pbt and add the smoothness of abs, many people would be happy.

For sliders, if you could make some that are infinitely smooth (slide with no resistance) yet retain the durability to last long, would be nice.
Title: Re: The Science of Keyboards
Post by: TheSoulhunter on Tue, 20 August 2013, 13:47:30
A wear resistant material with very low friction coefficient for sliders (no more lubing needed)

Found this...

Quote
Ultra high molecular weight polyethylene (UHMWPE), also known as high modulus polyethylene (HMPE) or high performance polyethylene (HPPE), is a thermoplastic. It has extremely long chains, with molecular weight numbering in the millions, usually between 3.1 and 5.67 million. The high molecular weight results a very good packing of the chains into the crystal structure. This results in a very tough material, with the highest impact strength of any thermoplastic presently made. It is highly resistant to corrosive chemicals, with exception of oxidizing acids. It has extremely low moisture absorption, very low coefficient of friction, is self lubricating and is highly resistant to abrasion (10 times more resistant to abrasion than Carbon Steel). Its coefficient of friction is significantly lower than nylon and acetal, and is comparable to teflon, but UHMWPE has better abrasion resistance than teflon. It is odorless, tasteless, and nontoxic.

Title: Re: The Science of Keyboards
Post by: Binge on Tue, 20 August 2013, 13:58:57
If you can come up with a wonder A/B low viscosity material that will harden at room temperature into a color neutral opaque or clear hard material that resists discoloring it would help us @home keycap casters

Just sort of dreaming here :3
Title: Re: The Science of Keyboards
Post by: tp4tissue on Tue, 20 August 2013, 16:43:27
If you can come up with a wonder A/B low viscosity material that will harden at room temperature into a color neutral opaque or clear hard material that resists discoloring it would help us @home keycap casters

Just sort of dreaming here :3

Ok, yea that sounds great, but how are we going to FUND this research project.


FIrst, may I suggest researching making meth and disguising them as keycaps to be sold on the black market.

:D,   then we can use the profits to take keycap science to "the next level".
Title: Re: The Science of Keyboards
Post by: rowdy on Tue, 20 August 2013, 17:22:43
PBT DS would be nice (although as above not for everyone).

Straight PBT space bars would also be nice.

POM DS??
Title: Re: The Science of Keyboards
Post by: BLJ Consulting on Wed, 21 August 2013, 19:52:43
Surface finish is much more a function of the tooling than the polymer selection.

For keycaps, if you could find a way to take something like pbt and add the smoothness of abs, many people would be happy.

For sliders, if you could make some that are infinitely smooth (slide with no resistance) yet retain the durability to last long, would be nice.
Title: Re: The Science of Keyboards
Post by: BLJ Consulting on Wed, 21 August 2013, 19:54:37
UHMWPE is a great material but cannot be injection molded TTBOOK; if there are moldable versions its unlikely to work for something as detailed as a overmolded keycap.


A wear resistant material with very low friction coefficient for sliders (no more lubing needed)

Found this...

Quote
Ultra high molecular weight polyethylene (UHMWPE), also known as high modulus polyethylene (HMPE) or high performance polyethylene (HPPE), is a thermoplastic. It has extremely long chains, with molecular weight numbering in the millions, usually between 3.1 and 5.67 million. The high molecular weight results a very good packing of the chains into the crystal structure. This results in a very tough material, with the highest impact strength of any thermoplastic presently made. It is highly resistant to corrosive chemicals, with exception of oxidizing acids. It has extremely low moisture absorption, very low coefficient of friction, is self lubricating and is highly resistant to abrasion (10 times more resistant to abrasion than Carbon Steel). Its coefficient of friction is significantly lower than nylon and acetal, and is comparable to teflon, but UHMWPE has better abrasion resistance than teflon. It is odorless, tasteless, and nontoxic.
Title: Re: The Science of Keyboards
Post by: mkawa on Wed, 21 August 2013, 21:50:07
the krytox fellows have a solid ptfe-like material that has the lubridicity of PFPE oil and the accompanying ultra-low COF. i believe it's a thermoset, however. because PTFE melts in a very bad way at 260C, it's hard to make an injection molded PTFE-matrix based solid, and PFPE doesn't really like many other polymers (heck, apparently it doesn't really like PTFE all that much, they just have a very clever way of fitting it into the gaps in PTFE matrices).
Title: Re: The Science of Keyboards
Post by: mkawa on Wed, 21 August 2013, 21:52:56
the other thing about UHMWPE is that we clearly don't need or want high impact resistance. in fact, a very mild elastomer with an extremely low coefficient of friction (likely a TPU) might even be ideal for the stems of linear switches. basically, the stem itself could act as a kind of bump-stop for bottoming out.

and of course as blj knows, I LOVE FLUOROELASTOMERS (right now) totally want to get some shot. it's like rubber, but it doesn't suck.

WOAH
Title: Re: The Science of Keyboards
Post by: tp4tissue on Wed, 21 August 2013, 22:23:04
the other thing about UHMWPE is that we clearly don't need or want high impact resistance. in fact, a very mild elastomer with an extremely low coefficient of friction (likely a TPU) might even be ideal for linear steps. basically, the stem itself could act as a kind of bump-stop for bottoming out.

and of course as blj knows, I LOVE FLUOROELASTOMERS (right now) totally want to get some shot. it's like rubber, but it doesn't suck.

WOAH

what you suggest would be more readily solved by re-engineering the key rather than applying some gel to existing keys..

the would never attempt to do the later before the former..
Title: Re: The Science of Keyboards
Post by: TheSoulhunter on Wed, 21 August 2013, 23:48:25
UHMWPE is a great material but cannot be injection molded TTBOOK; if there are moldable versions its unlikely to work for something as detailed as a overmolded keycap.


A wear resistant material with very low friction coefficient for sliders (no more lubing needed)

Found this...

Quote
Ultra high molecular weight polyethylene (UHMWPE), also known as high modulus polyethylene (HMPE) or high performance polyethylene (HPPE), is a thermoplastic. It has extremely long chains, with molecular weight numbering in the millions, usually between 3.1 and 5.67 million. The high molecular weight results a very good packing of the chains into the crystal structure. This results in a very tough material, with the highest impact strength of any thermoplastic presently made. It is highly resistant to corrosive chemicals, with exception of oxidizing acids. It has extremely low moisture absorption, very low coefficient of friction, is self lubricating and is highly resistant to abrasion (10 times more resistant to abrasion than Carbon Steel). Its coefficient of friction is significantly lower than nylon and acetal, and is comparable to teflon, but UHMWPE has better abrasion resistance than teflon. It is odorless, tasteless, and nontoxic.

So, is there a thermoplast which is "though" enough to be used as keystem/slider, with very low friction coefficient, which also can be injection molded?
Title: Re: The Science of Keyboards
Post by: mkawa on Thu, 22 August 2013, 00:24:44
well the problem with injection molding is, as BLJ said, the surface of the mold has a lot more to do with the friction characteristics than the material. thermosets are a bit easier to get a smooth surface on but the ideal thing is to hand or machine finish the surface to be smooth then lubricate it with, for example, the most advanced polymer lubricant ever made. the advantage of the thermoset version with the pre-preg oil for lubridicity is that it is a solid, so for situations in which the material is exposed, it will be more durable to use the pre-preg solid.

however, if your slider is enclosed, you can just use a bearing joint grease. so basically if you want smooth linear sliders you guys are doing the optimal thing, and as much as my dupont rep is incredibly shocked that you guys put the effort into it, he is quite happy to point out that you get an optimal surface that way.
Title: Re: The Science of Keyboards
Post by: TheSoulhunter on Thu, 22 August 2013, 00:55:53
Nah, no lubrication at all...
The initial thought was to use a different material so we can abandon lubing the stems but still having smooth travel for years ;)
Title: Re: The Science of Keyboards
Post by: tp4tissue on Thu, 22 August 2013, 03:02:45
well the problem with injection molding is, as BLJ said, the surface of the mold has a lot more to do with the friction characteristics than the material. thermosets are a bit easier to get a smooth surface on but the ideal thing is to hand or machine finish the surface to be smooth then lubricate it with, for example, the most advanced polymer lubricant ever made. the advantage of the thermoset version with the pre-preg oil for lubridicity is that it is a solid, so for situations in which the material is exposed, it will be more durable to use the pre-preg solid.

however, if your slider is enclosed, you can just use a bearing joint grease. so basically if you want smooth linear sliders you guys are doing the optimal thing, and as much as my dupont rep is incredibly shocked that you guys put the effort into it, he is quite happy to point out that you get an optimal surface that way.

which way? you put alot of things in there, which one are you saying is optimal
Title: Re: The Science of Keyboards
Post by: meiosis on Thu, 22 August 2013, 03:16:49
As a premed student I didn't understand a thing in this thread, other than the full caps acronyms that look like DNA
Title: Re: The Science of Keyboards
Post by: CommunistWitchDr on Thu, 22 August 2013, 07:39:09
How do we make meth into keycap shape..

Then we can sell large quantities as collectables, while charging the Meth price...

and the Authorities wouldn't know any better  :D
Heisenboard.
Title: Re: The Science of Keyboards
Post by: BLJ Consulting on Thu, 22 August 2013, 08:03:11
Nah, no lubrication at all...
The initial thought was to use a different material so we can abandon lubing the stems but still having smooth travel for years ;)

POM (aka Acetal) is generally known as a self lubricating plastic.  Many moving parts and most molded gears are made using POM.  POM is also very dense so the same geometry will be about 30% heavier than an ABS cap - I know some people are into that.  I made some samples of these last year and they are for sale on the sp pimpmykeyboard site along with the double shot PBT and TPU (rubber) keys.
Title: Re: The Science of Keyboards
Post by: tp4tissue on Thu, 22 August 2013, 08:50:12
How do we make meth into keycap shape..

Then we can sell large quantities as collectables, while charging the Meth price...

and the Authorities wouldn't know any better  :D
Heisenboard.

Mmm hmm hm hm hm hm hm hm..... :D

waiting for new episodes each week is killing me.... agggggggghhhh.. :eek: