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geekhack Community => Keyboards => Topic started by: chyros on Wed, 25 January 2017, 05:38:03

Title: Teardown - Cherry MX
Post by: chyros on Wed, 25 January 2017, 05:38:03
Bit back to basics with this, but today we look at how Cherry MX switches work! :)

Title: Re: Teardown - Cherry MX
Post by: tp4tissue on Wed, 25 January 2017, 07:24:46
I thought the primary function of the gold was because it's soft, therefore making better microscopic contact...

is corrosion resistance more important than the softness..  or was the softness a myth all along.
Title: Re: Teardown - Cherry MX
Post by: chyros on Wed, 25 January 2017, 07:45:14
I thought the primary function of the gold was because it's soft, therefore making better microscopic contact...

is corrosion resistance more important than the softness..  or was the softness a myth all along.
My arse is soft as well, wouldn't make great contact material :p . The gold is there to increase the lifetime of the switches, not for contact purposes, that's what the crosspoint is for. In fact, a sharper contact point is better.
Title: Re: Teardown - Cherry MX
Post by: Rayoui on Wed, 25 January 2017, 08:20:06
Gold actually has a lower electrical conductivity than copper and silver. However, those metals readily oxidize which impedes electrical signals. Gold is one of the most corrosion resistant materials on Earth. That is why it's used for things like switch contacts and connectors on cables.
Title: Re: Teardown - Cherry MX
Post by: tp4tissue on Wed, 25 January 2017, 14:17:45
are you guys sure the softness has nothing to do with it ?
Title: Re: Teardown - Cherry MX
Post by: Rayoui on Wed, 25 January 2017, 14:52:05
Yes. Gold alloys used in electronics are for corrosion resistance. The "softness" of the metal doesn't allow it to make a better contact, it's the fact that it isn't oxidized that minimizes resistance.

Cherry's gold cross-point contacts are made of a gold-silver alloy they call "AuAg 10." The rest of the leaf is made of gold-plated beryllium copper.