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#1 2015-08-03 05:27:11

bbraun
Member
Registered: 2014-05-29
Posts: 1,064
Website

Keycap replacements

I have an AEKII with a broken spacebar.  I thought 'hey, how hard can it be to make a new one?'.  Well, haha.
There's a lot of resources out there for keyboard modding, but couldn't find a premade AEKII spacebar.

Here's some pics of my first attempt, which fits the ALPS keyswitch in the center, and has the support post that's on the left side of the spacebar, but it doesn't have the clips for the metal bar that kinda holds the key level.  So when I press on an edge, particularly the right edge, the key wants to tilt, which negatively affects all kinds of things.  I'll see if I can figure something out for the tabs for the metal bar in my next iteration:

IMG_0180.JPG
IMG_0182.JPG

The weird texturing is because I needed to have supports when printing this.  I like to print directly on the build platform, but it wasn't really practical with this version.  So, I had supports, and when I remove the supports, it leaves marks on the surface.  These marks are all on the underside, and I haven't sanded them all down yet.  This was mainly to see if it fit and if it was a practical replacement.

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#2 2015-08-03 09:44:24

uniserver
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From: Sf, Mi
Registered: 2014-05-15
Posts: 956
Website

Re: Keycap replacements

wow … that is awesome!,  you are really getting your moneys worth outta that nifty machine you have.

I am really curious what you might come up with to compensate for the metal bar and the tabs…

you get an A ++ if you can figure out how to compensate for all that using something made from the 3d printer HAHA.

Last edited by uniserver (2015-08-03 09:44:42)


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#3 2015-08-03 14:51:20

bbraun
Member
Registered: 2014-05-29
Posts: 1,064
Website

Re: Keycap replacements

As a rough idea, this is the problem I'm trying to solve:
IMG_0184.JPG

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#4 2015-08-04 02:15:55

bbraun
Member
Registered: 2014-05-29
Posts: 1,064
Website

Re: Keycap replacements

I added little places for the edges of the metal bar to go, but it's still not great.  The side with the long post seems to get stuck fairly regularly and the spacebar gets uneven.

There's a couple things I'm thinking:
1) the whole thing is heavier than the original spacebar, so I'm wondering if it's just a bit heavy for the switch to push back up.
2) the support post is maybe 1mm shorter than the original, so I'll try fixing that.
3) there's maybe half a millimeter of extra play where the metal bar sits
4) the original clip for the metal bar actually prevented the bar from moving too far out.  I initially thought this was just to prevent the bar from coming off the key, but I'm now wondering if it actually provides some springing action when the key bottoms out.

IMG_0185.JPG

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#5 2015-08-04 10:07:11

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,408

Re: Keycap replacements

Is that a rubber cap on the post under the stock cap? If it became hard with age, that might account for the failure. If your posts have no give, that might be a problem?

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#6 2015-08-04 15:37:20

bbraun
Member
Registered: 2014-05-29
Posts: 1,064
Website

Re: Keycap replacements

No exposed rubber here.  There might be rubber inside the switch mechanism its self, but the switch more or less works as expected.  It's something with my model.

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#7 2015-08-06 01:15:32

bbraun
Member
Registered: 2014-05-29
Posts: 1,064
Website

Re: Keycap replacements

I lightened it up by reducing the wall thickness from 3mm to 1.2mm, extended the support post by 1mm, and moved the metal bar retainers up by 1mm, and now it works substantially better.  It's still curing, so results are still preliminary, but very promising.
I could probably thin the walls a little further, but I prefer to err on the side of too sturdy with these things.  My first attempt had the walls 0.8mm thick, and due to the way I am printing it, the "top" of the key didn't work out.  I'm actually printing it upside down so all the supports go on the inside of the key in order to keep the outside smooth.  I suspect if I angled one side up a bit, I'd get some better prints, since it would allow the resin to drain out one side as it is being printed.

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#8 2015-08-06 19:03:34

bbraun
Member
Registered: 2014-05-29
Posts: 1,064
Website

Re: Keycap replacements

Boom!  I think I've finally got it.
Here's a picture of the model so you can see all the attachments on the bottom of the key:
spacebar.png
Here's a picture of the installed key:
IMG_0188.JPG
And here's the STL file

The key is now light and responsive and doesn't get tilted unevenly when pressing on the edges.  A totally acceptable replacement IMO.

Here's what printing it looks like, in the printing software.  It'll print upside down from how it appears here (the "bottom" in the picture is the build platform, which is upside down in the printer).
spacebarprint.png

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#9 2015-08-06 22:51:42

techknight
Member
Registered: 2014-05-22
Posts: 449

Re: Keycap replacements

Make them a little bit more opaque, and use LEDs :-) Backlit AEKII

With a CNC, you could etch the numbers/letters/symbols into the translucent keys, and fill the recesses with paint.

Last edited by techknight (2015-08-06 22:59:36)

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#10 2015-08-06 22:57:35

bbraun
Member
Registered: 2014-05-29
Posts: 1,064
Website

Re: Keycap replacements

Hah!  The rest of the keys should be easy, it's just the spacebar on the AEKII is weird, since it uses a single keyswitch in the middle, a  single support post on the left side, and then that metal bar to keep everything balanced, rather than a support post on either side.
I've thought of doing other designs on the keys as well.  Some people seem to like skull designs on some of the less used keys for decoration.  Probably could do something like that for the power button.
In my case, I had a broken key and needed a replacement, more than ricing out my AEKII.  smile

Meanwhile, my desk is littered with failed spacebars.

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#11 2015-08-06 23:02:03

techknight
Member
Registered: 2014-05-22
Posts: 449

Re: Keycap replacements

Yea, I am thinking backlit keys, Either use opaque letters CNC milled into the keys, Or, Raise the letters a slight bit and then paint the keys, and wipe off the raised areas where the light passes through.

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