Stuck fukka switch

[msiegel]

i modified a filco zero, replacing all the sliders with AEK II dampened sliders.  this works well, except for the F7 key.

the switch is stuck ON, even without the housing or other components attached.

before realizing the switch is stuck ON not OFF, i disassembled & reassembled it four or five times, swapping the housing, slider, and click leaf, and there was no change.

unfortunately i can't get a close-up shot of the switch-contacts assembly, but to my eye there are no obvious bends or damage.

anyone have ideas?

[wellington1869]

a reeeallly slow scan rate? :-D

but seriously, maybe there's something lodged under the bendy lever on the switch mechanism? I'm sure you've checked but thats the most obvious answer, that even if it looks like its not making contact, that something is making contact.  Maybe stick a piece of cardboard in between lever and switch and see if you can disconnect the contact thats being made?

alternately, did anything get on the pcb?

alternately, is it a combo of other keys that are pressed/stuck which are producing f7 via their combination?

[lal]

Ripster, what switch and board is that pic from?

[lal]

A quick look over the Alpsulator thread didn't show pics from the switch internals.  Does is it have the narrow bronze click leaf?  And do they feel balky to you?

[lal]

ignore

[lal]

Great you joined the league

[wellington1869]

Clicky white XM from the red calculator.  At least I think it's a XM - I'm no ALPS expert.

if it has a "narrow" click leaf then its basically XM (or the family of clones/"types" represented by the xm).

[msiegel]

Do these Fukka's have that slot at the top of the housing that the switch portion must slide into?

the housing has an enclosed slot for the contact assembly, with a cutout that the lever projects out of

i'll try that toothpick trick...

[msiegel]

hmm, if i tweak around with the lever/contacts, i can get F7 to turn off.

i'll play with this more in a little while

[wellington1869]

hmm, if i tweak around with the lever/contacts, i can get F7 to turn off.

i'll play with this more in a little while

sounds like a stucka fukka indeed.

still waiting for your review

[bigpook]

I hosed up the escape key on my xm tenless within days of owning it. I just had to take a key apart to look at it. In the future, like now, I start with a non-critical key; like the pause key.
I never did get it fixed though. Those copper leafs are very delicate and it doesn't take much to damage them.

One solution is to completely replace the switch. I think thats what the black alps in the Dell are for : )

[bigpook]

You can fix them eventually.  It's a matter of trial and error.  Bend the metal so it looks like another switch.  Then adust (bend) the two little tabs that actually make the on/off contact.

Helps to swear constantly while cleaning the contacts with 100% isopropyl alchohol and waving a cigarette  lighter in front of it.

: ) fire, fire, fire.

[bigpook]

Actually you don't have to swear.  Just keep chanting "Fukka, Fukka, Mother FUKKA" and it will eventually work.

actually, I did try that. Didn't work though... : (

[msiegel]

thanks guys.

i played around with it for awhile, then got impatient and replaced the switch...

there's a pic of the result in Keyboard Pics

[bigpook]

thanks guys.

i played around with it for awhile, then got impatient and replaced the switch...

there's a pic of the result in Keyboard Pics

Sometimes that may just be the easier thing to do.

[wellington1869]

Sometimes that may just be the easier thing to do.

that assumes soldering skills.  I still cant believe how many switches I destroyed when I put a soldering iron in my hand. I mean it was genocide. I'm sorry, but it was just switch genocide.  I feel racked with guilt. We need a nuremburg trial for me.

[wellington1869]

The funny thing is, I used to solder those fine surface mount chips onto circuit boards back in my brief engineering career when we'd debug boards.  I got pretty good at that, too.  The only thing I can think of is the thickness of the leads is what threw me. I've always only ever soldered those fine leads on the smt chips. It just takes a touch with the iron. On the alps switches those damn things just would NOT heat up. No wonder I fried all of them trying to just melt the damn solder.

[bigpook]

Its been many years since I soldered. So doing the xm | black alps swap was interesting. I damaged two of the black alps switches during the swap but figure that to be pretty good. I realized going in that excessive heat would most likely damaged them. I think the heat will soften the plastic around the pins and throw it out of wack.

but sometimes you don't have much choice. I had mangled the xm switch to the point of no return. I ended up remapping the key just to get around it. It wasn't much later when I swapped them all out.

We are a crazy bunch here. The things we do to our keyboards...

[erricrice]

We are a crazy bunch here. The things we do to our keyboards...

Horrible unspeakable evils...

[wellington1869]

I had three stukka fukkas when I was done. After about 2 hours of meticulous investigation (i was paranoid that i'd break something beyond recovery) I found that there is a screwdriver trick. It worked on each of my switches, so I have to think its a common thing that can go wrong. So thought i'd mention it here in stukka fukka.

Basically I used aquakeytest.exe, and it showed no closed switches. So they were open. Touch it with toothpick, and they close just fine. Put in the housing - and no response when you click them.  Whats the deal? The housing is the problem?

Yep, amazingly the housing was the problem. Turns out, in the slot that covers the switch, there are little plastic separators to separate the very thin leaf from the more firm strike plate. In my case for whatever reason they werent going into their slot (I think they were going into the same slot, tho this didnt cause them to close for some reason).

Solution was to stick a precision screwdriver between them and separate them a bit (for the first hour I kept trying to bring them together since I thought they werent making contact). After that everything worked instantly and the other two switches took 2 minutes to fix.