[SOLVED] dismantling cherry MXs. A switch is ON when it has no spring and leaf

[urlwolf]

I may have made a huge mistake (dismantling cherry MXs),...
I removed the swiches from the nunpad of a cherry G80-3000 keyboard.
Following this:
http://www.youtube.com/watch?v=GivKt63dLvA

I wanted to cover the space and use it to place a trackpad there (ghetto tenkeyless?).

When I plug the usb cable, the kb doesn't work.
Knowing nothing about electronics, I can think of tho things:
1- broke the board when pulling swtiches.
2- some electronic feature (resistance?) changes when you remove switches. the keyboard expects say 100 switches, now it has say 80, calculations don't work. But I doubt this, since I did the 'no soldering' version, all switches are there, only the stem and leaf is missing.

Ideas about testing? Workarounds?

Thanks!

[7bit]

I may have made a huge mistake (dismantling cherry MXs),...
I removed the swiches from the nunpad of a cherry G80-3000 keyboard.
Following this:
http://www.youtube.com/watch?v=GivKt63dLvA

I wanted to cover the space and use it to place a trackpad there (ghetto tenkeyless?).

When I plug the usb cable, the kb doesn't work.
Knowing nothing about electronics, I can think of tho things:
1- broke the board when pulling swtiches.
2- some electronic feature (resistance?) changes when you remove switches. the keyboard expects say 100 switches, now it has say 80, calculations don't work. But I doubt this, since I did the 'no soldering' version, all switches are there, only the stem and leaf is missing.

Ideas about testing? Workarounds?

Thanks!

You did the board an enormeous amount of pain!

Think of pulling teeth without anaesthesia!

You killed the keyboard! It died of pain!

KILLER!!!!!!!!!!!!!!

[Nadger]

Is it even getting power?  Do LEDs turn on/off?  Does windows acknowledge that you plugged something in?  Does it hurt when you urinate?

[Findecanor]

The keyboard should work without there being switches [strike], or sliders in the switches.[/strike]

You could have broken a connection or added one. Some suggestions:
[strike]* Check if the cable's wires are attached correctly at the PCB. Perhaps a wire could have been pulled apart at the soldering pad when you opened the case.[/strike]
* Check for foreign objects on the PCB, such one of the springs. Several Cherry keyboards have bare metal jumpers on the top side of the PCB.
* Check for damage to the soldering pads on the back of the PCB, in case you would have damanged a switch by pulling it too hard. The switch's signal lines don't matter, but if a switch does not have a diode, then it could have a jumper that could carry some important signal.

http://www.youtube.com/watch?v=GivKt63dLvA

Hmm.. but,, that guy uses the kind of tool I use to open ALPS switches ...

Edit: Me stupid

[urlwolf]

Is it even getting power?  Do LEDs turn on/off?  Does windows acknowledge that you plugged something in?  Does it hurt when you urinate?

Yes, the 3 leds light up when the usb cable is in (then they go off).
OSX does show that a  kb has been plugged. It ask all the silly 'what is the key next to left shift' questions. Linux doesn't see it, but I run a barebones install (no desktop, just xmonad), so let's not think about linux now. I haven't tried win.

[7bit]

Yes, the 3 leds light up when the usb cable is in (then they go off).
OSX does show that a  kb has been plugged. It ask all the silly 'what is the key next to left shift' questions. Linux doesn't see it, but I run a barebones install (no desktop, just xmonad), so let's not think about linux now. I haven't tried win.

Here is a picture of that region:

Do you see those little wires in the switches?

I guess these connections must be reinstalled to re-animate your Cherry-board.

[Lanx]

did you mash the controller? i'm guessing that the controller is above the numpad, maybe you did something, there, as always if you want help, take pictures.

[Soarer]

Do you see those little wires in the switches?

I guess these connections must be reinstalled to re-animate your Cherry-board.

This. Definately. Solder some links back in there first.

[urlwolf]

First, apopogies for the quality. It's nightime here, and I only have a N1 phone with no macro and no control over flash... I can retake pics on any area you tell me to.
Since I'll probably have to upload many more pictures, I'll put them on dropbox:

http://www.dropbox.com/gallery/103582/1/cherry?h=99db2c

The keyboard should work without there being switches, or sliders in the switches.

You could have broken a connection or added one.

I found one switch had been deformed, it might have added a connection.
I marked it with a piece of black cardboard (see pic). it also prevents the switch from making contact.

Some suggestions:
* Check if the cable's wires are attached correctly at the PCB. Perhaps a wire could have been pulled apart at the soldering pad when you opened the case.

* Check for foreign objects on the PCB, such one of the springs. Several Cherry keyboards have bare metal jumpers on the top side of the PCB.

I collected all the springs. There were some hairs that I removed.

* Check for damage to the soldering pads on the back of the PCB, in case you would have damanged a switch by pulling it too hard. The switch's signal lines don't matter, but if a switch does not have a diode, then it could have a jumper that could carry some important signal.

Looks like to look at the  back of the PCB I have to unsoder a cable. I've never done it, and don't have the tools (plus it's Sunday  ).

Looks like pulling the leaf from cherry MXs is actually not risk-free, I can see at least 2 switches that look different.

BTW, where was this animation on how the contact is made with cherry switches?

Thanks!

[urlwolf]

did you mash the controller? i'm guessing that the controller is above the numpad, maybe you did something, there, as always if you want help, take pictures.

I took pictures of the controller, but not sure they are detailed enough...

[lowpoly]

But I doubt this, since I did the 'no soldering' version, all switches are there, only the stem and leaf is missing.

It's not the missing wires. The 'board should work. Try re-seating the ribbon cable.

[Soarer]

Ahh... I see what you've done now. That won't work I'm afraid. When there's no slider in a Cherry switch it's 'pressed'.

[Soarer]

This is what I did to get rid of some keys without removing them: cut the tops off the sliders (I used some I had plenty of spares of!)...

[urlwolf]

This. Definately. Solder some links back in there first.

Just to make sure... are we talking about the little silver links next to the switches on the PCB, or the little cylinders inside the switches? They all look ok at first sight, nothing looks obviously broken (but what do I know )

[Soarer]

Just to make sure... are we talking about the little silver links next to the switches on the PCB, or the little cylinders inside the switches? They all look ok at first sight, nothing looks obviously broken (but what do I know )

Sorry, ignore that now We thought you'd desoldered the switches from the board.

[bpiphany]

Shouldn't it be enough to insert some thin plastic to push the leafs apart? And I don't see how desoldering the switches could have any effect other than rendering that particular button inactive... Good catch that the cherrys stay closed when the slider is out though =)

[nanu]

Ahh... I see what you've done now. That won't work I'm afraid. When there's no slider in a Cherry switch it's 'pressed'.

^ What he said. The slider in an MX switch holds it open until it's pressed and the spring action closes the circuit again. You could slip in some paper or plastic sheets between the crosspoint of the contact leafs.

Beat me to it, I blame recent connection problems :whistle:

...

[7bit]

Just to make sure... are we talking about the little silver links next to the switches on the PCB, or the little cylinders inside the switches? They all look ok at first sight, nothing looks obviously broken (but what do I know )

These little 'cylinders' make it have n-key rollover.
If you connect the board, and keys are pressed, while you make connection it might not work. Maybe it is not working because the keys are in key-pressed state.

[lowpoly]

only the stem and leaf is missing

What do you mean when you say leaf?

[Findecanor]

I gave you bad advice earlier. I'm sorry. I was confused.
Listen to Soarer.

[urlwolf]

Ahh... I see what you've done now. That won't work I'm afraid. When there's no slider in a Cherry switch it's 'pressed'.

Thank you !
This explains things!
Let me put them back and see how things look...

[urlwolf]

Ok, I'm back to normal!
Thanks a lot to all for your help.
The board was not working because the were are in key-pressed state. I'll mark this as solved.
If anyone has any ideas on how to make a 'ghetto tenkeyless' out of a MX 80-3000, please let me know!
I may try cutting the endings on 'blacks'; this would definitely be a solution... Will need to get some black XM donnor first. Being in DE, not so difficult, although our ebay seems to be depleted of deals lately...

[Soarer]

Phew! Panic over :-)

If it were me, I'd desolder the switches. If you're not confident with a soldering iron that might not be wise...

How deep is the trackpad? (Cutting the stems level with the switch case only lowers them to about the level of the inside of keyboard case).

[urlwolf]

yeah, my hack was assuming you couldn't get any better than case surface. So it'll stick out. It's a filco trackpad. It cannot be housed in the numpad hole, but it's close.
But I changed my mind, I think a kensington orbit track ball would be better. This is very wide and cannot be housed in the numpad hole.
I won't try desoldering, on this board. I'll get a cheap one to try it first. Something with blacks, and then mod it with sixty's springs to get ghetto reds.