Filco MX blue switches starting to fail

[csimi]

Hey guys.
I'll need some help troubleshooting a problem with my Filco.
Some (mx blue) switches on the left side of my Filco MJ1 tenkeyless keyboard started to act weirdly.
They don't work pretty often, less often they type double.
First it was only left ctrl, then after a few days left shift, few more days d, some more time and 1.
It feels weird that all of a sudden 4 switches would die within at most 2 weeks, all on the left side of the keyboard. I didn't spill anything it.
Is it possible that it's a bad batch of switches?
Could anyone with some experience please help me?

Edit: Looks like it was the switches, after soldering in some new ones it's working properly now.
It's still weird that 5 of them started to die within a 2 week period without having any spills.

[RiGS]

I'm sorry to hear that. It could be PCB or controller related.

[RiGS]

I doubt that there is any problem with the switches itself. Is this your custom Filco with the metal MKC case?
I heard some rumors about the PCB shorting on the metal case. In this case the problem may be a stand off in the wrong spot.
Have you experienced this problem with the regular plastic Filco case?

[csimi]

I doubt that there is any problem with the switches itself. Is this your custom Filco with the metal MKC case?
I heard some rumors about the PCB shorting on the metal case. In this case the problem may be a stand off in the wrong spot.
Have you experienced this problem with the regular plastic Filco case?

Yes, it's that one.
I hope it's not the PCB since it's the only unreplaceable thing if it gets permanent damage.
I'll try the keyboard outside of the case.

[RiGS]

Let me know how it goes.

[firebt]

Let me know how it goes.

Cherry MX switches rarely fail, they're rated to 50 million clicks and due to their simplified design, it's hard to for a plunger to stop putting a metal plate from touching another one. 

That being said, yes, Rigs has a point, most likely PCB related.  Check all the connections, perhaps you can warranty with Filco.  Let us know

[PointyFox]

Diatec may fix your keyboard out of warranty anyway because they're cool like that. 

[csimi]

Finally had some time to investigate.
The keys don't work properly even outside the case and now even r is starting to fail.
Anodized aluminium shouldn't conduct electricity anyways, right? And the case standoffs are not even in contact with the pcb.

Edit: It works all the time with the HID Liberation Device controller, though it registers double or triple keypresses for problematic keys and very rarely double for not yet affected ones. Weird.
Edit2: I even had one weird case when the next letter inserted between repeated characters.

[tp4tissue]

Sounds like cracked PCB.. check carefully.

[csimi]

Sounds like cracked PCB.. check carefully.

I'm not sure. I'll check it again the next time I take this beast apart. Until then I'll try tinkering with the firmware, it might be the fix I needed.

[link_tree]

did you try the keyboard on a different machine?

[kbfreak]

possibly loose solder point(s)? assuming no shorting from the aluminum case, and cherry mx's 50 million stroke life span, that's what I can think of.

[rknize]

That or the aluminum has worn through one or more traces for the matrix column(s) that contains those keys.  Very unlikely to be the switches.  Look at the traces both near the switches and over by the header for the controller.