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geekhack Community => Keyboards => Topic started by: CX23882 on Sat, 24 January 2009, 15:38:16

Title: Rubber dome durability
Post by: CX23882 on Sat, 24 January 2009, 15:38:16
I'm well aware of the benefits of mechanical switches or buckling springs, but in terms of durability and longevity, are they superior to rubber domes?  I have a Fujitsu keyboard from 1997 that was heavily used from 1997 until 2003 and is still used daily for a couple of hours a day (albeit not on the main PC).  Although the keycaps are almost mirror reflective through wear, the keys are functionally fine.  No keys have stiffened up, no keys have bounce problems, no keys have to be hit hard.

It seems to me that a mechanical switch has a lot more that can go wrong than a simple sheet of rubber.

What are your thoughts?  On the other hand, if something goes wrong with a rubber dome, the whole board is useless whereas switches can be individually replaced.

(on the other hand we have some Dell USB keyboards at work that have several very stiff keys after a couple of years)
Title: Rubber dome durability
Post by: bhtooefr on Sat, 24 January 2009, 16:03:16
Mechanical switches have a lot more to go wrong, but they're also built out of metal and plastic, not rubber.

Here's a comparison... MTBF for a single key on a Unicomp keyboard. 25 million strokes for BS, 10 for rubber dome.
Title: Rubber dome durability
Post by: Chloe on Sat, 24 January 2009, 16:09:35
The lowest rating I have seen for mechanical switch was 8 million presses for fake simplified ALPS. It is low compared to Cherry MX (50 million presses) but I think that is still higher than most rubber domes.

I think mechanical switches are more durable but there are rubber dome keyboards that have high ratings such as Cherry G86 range (25 million presses). These are aimed at industry so I don't know how nice they feel to type on.
Title: Rubber dome durability
Post by: CX23882 on Sat, 24 January 2009, 16:22:03
The Cymotion Expert (G86 family) is rated for >20 million keystrokes, and it is nice to type on, to the point that it doesn't feel like a regular rubber dome, to my fingers at least.
Title: Rubber dome durability
Post by: lam47 on Sat, 24 January 2009, 17:24:52
What about the domes in a HH? You would want that to last :)
Title: Rubber dome durability
Post by: xsphat on Sun, 25 January 2009, 00:58:53
Quote from: lam47;19505
What about the domes in a HH? You would want that to last :)


Don't worry about it.

I have a feeling those numbers are a wild guess anyway. So you think Cherry has a machine to depress their switches 50 million times? Doubt it. And there is a national columnist who has used the same Model M since it was new (metal logo on the right side) and he cleans it every so often. This guys writes like I do and for over twenty years? That's probably over 25 million hits on his tilda key. My Northgate was obviously rode hard and put away wet for years, and it still clicked away fine. I think if you treat these keyboards like we all do, they will last for a long, long time.
Title: Rubber dome durability
Post by: lal on Sun, 25 January 2009, 05:22:26
Quote from: xsphat;19551

I have a feeling those numbers are a wild guess anyway. So you think Cherry has a machine to depress their switches 50 million times? Doubt it.


They do, e.g.:

(http://images.pcwelt.de/images/pcwelt/bdb/20947/800x.jpg)
Title: Rubber dome durability
Post by: lowpoly on Sun, 25 January 2009, 07:02:29
Quote from: lal;19561
They do, e.g.:
Link please?
Title: Rubber dome durability
Post by: Chloe on Sun, 25 January 2009, 08:07:43
http://www.pcwelt.de/start/computer/peripherie/praxis/34873/report_so_entsteht_eine_tastatur/
Title: Rubber dome durability
Post by: lam47 on Sun, 25 January 2009, 08:08:57
Wow that thing is cool!
They would have to actually test the switch until it failed to be able to make the claim I would think.
I know arcade buttons go through the same process.

I want one now :)
Title: Rubber dome durability
Post by: lowpoly on Sun, 25 January 2009, 10:10:20
Thanks, Chloe.
Title: Rubber dome durability
Post by: lowpoly on Sun, 25 January 2009, 10:46:24
Good 25 pages article with lots of background information on Cherry production (article in german).
Title: Rubber dome durability
Post by: Eclairz on Sun, 25 January 2009, 13:24:51
I just wish it was in english :-(
Title: Rubber dome durability
Post by: Chloe on Sun, 25 January 2009, 13:32:42
Translated:
http://translate.google.com/translate?prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fwww.pcwelt.de%2Fstart%2Fcomputer%2Fperipherie%2Fpraxis%2F34873%2Freport_so_entsteht_eine_tastatur%2F&sl=de&tl=en&history_state0=

This life test machine looks a little scary:
(http://www.switronic.com/Images/Apparatus/Apparatus_3.jpg)