*yawwwwwnnnn* "This will probably be at least a 3-coffees move."
Allright... maybe slightly more than 3 coffees... The mouse on my workshop PC has developed a hinky left button, resulting in very random double-clicks and dropouts while highlighting...
On the Bench This Morning: Nuking the MouseSo
old faithful crusty old Dell optical mouse started giving me fits this morning; or at least the fits it was having got consistent enough that I actually noticed.
Since I'm at the bench already, I decided to minimize wasted time searching for a replacement I'm not even sure I have ATM and just service the thing using this process I learned and developed while doing fleet maintenance at the ISD. Once you get to where you know what you're doing and you have "the usual stuff" right out on your bench, it literally takes 10 minutes. Provided you aren't stopping to snap pics and do a write-up.
![Wink ;)](https://www.eevblog.com/forum/Smileys/default/xwink.gif.pagespeed.ic.cldandycH0.png)
This mini-DIY applies to pretty much any situation where you might have one of these micro-switches and don't have a replacement handy, or are stuck without means to desolder the switch; they actually usually can be made pretty much 100% good again at least once or twice following this procedure.
I'm going to start right at the point of actually "reconditioning the switch"; I'm reasonably sure everyone in here already knows how to dismantle a mouse and desolder a switch. I had to take my mouse apart again to get some of the high-detail pics (you're welcome
![Wink ;)](https://www.eevblog.com/forum/Smileys/default/xwink.gif.pagespeed.ic.cldandycH0.png)
); this makes continuity seem weird. You
can do this without desoldering the switch in some cases where things like the scroll decoder aren't in the way.
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533589;image)
Pop the top off by slipping a knife-point under these tabs on both sides of the switch.
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533595;image)
Remove the leaf-spring contact by unhooking from the contact hook in switch body. Pull gently and upward slightly using dental pick or similar instrument.
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533601;image)
There will be a little silver contact on the leaf-spring; the most common failure mode is this gets a little divot worn in it compounded by tarnish build-up. I didn't get a good shot for the before pic, I'm afraid.
![Undecided :-\](https://www.eevblog.com/forum/Smileys/default/undecided.gif.pagespeed.ce.cCZ6w-jWpR.gif)
The cure is to buff it down with very fine sandpaper (like 800-2000 grit); I use this fingernail buffing board. Yeah, I know it's pretty horrible looking; it's prolly older than my daughter.
![Wink ;)](https://www.eevblog.com/forum/Smileys/default/xwink.gif.pagespeed.ic.cldandycH0.png)
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533607;image)
Next step is to retension the recurve spring by squeezing gently in flat-jawed pliers. About 1/2 to 3/4 compressed is all it takes to get good tension again; if you flatten it too much the hardened brass leaf will crack.
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533613;image)
Next is to clean the lower contact; I do this by scrubbing with a fine-bristle wire brush. You'll need to angle the brush to get under the keeper hook and scrub the lower contact with the side of the wires.
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533619;image)
After that, I clean
everything; leaf-spring and switch base, and inside the cap, with a paintbrush and IPA. Here you can see the lower contact and keeper hook a little more clearly. When working on the bench, I'll accelerate the drying with very conservative application of a hot air gun.
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533625;image)
Now it's time to reassemble the micro-switch; this can be done by hand (once you get to where you know what you're doing) or with tweezers. First you get the contact under the keeper hook, then you catch the end of the recurve spring under the hook in the middle. Then you pull the end of the leaf spring down over the shoulder of the outer contact hook into the first notch.
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533631;image)
You can now test the switch before reassembling; by pressing down here between the two contact hooks in the switch base (there will usually be a visible wear/polish line from the switch plunger), you can make the switch actuate as in normal use. It should have a crisp, positive detent action without feeling crunchy or snaggy. If you've assembled it correctly, you do not have to worry about the leaf-spring flying off.
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533637;image)
Now it's time to reassemble the cap onto the switch.
Always reassemble with the cap upside-down so you don't lose this little gawddammitt. It
will escape and be lost forever in the middens under the bench, desk, bedroom etc if given
any chance to do so.
![Shocked :o](https://www.eevblog.com/forum/Smileys/default/xshocked.gif.pagespeed.ic.CrwtrNUjLO.png)
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1533643;image)
And last step, A little PM. Yeah, okay... the USB cable hasn't broken a wire
yet and left you mouse-less. By relocating the captive portion of the wire so that the old "strain-point" is now kept inside the mouse, you can make it so the strain is now primarily concentrated in a new area of the cable, thereby increasing its future life expectancy. All it takes is to pull the cable back into the mouse 20-30mm or so, then tuck the excess away like so.
After that, finish up by reassembling the shell and screws, then the usual wipe it all down ith IPA, especially the Teflon slider pads to clean off the body-oil grunge that makes it not slide like it should.
Then you can test it like I did: by editing a mess of pics, and spending 3 hours to chronicle a 10-minute fix.
![Laughing :-DD](https://www.eevblog.com/forum/Smileys/default/smiley_laughing.gif.pagespeed.ce._hfWAz_QHO.gif)
mnem
*mouse-ily again* ![Tongue :P](https://www.eevblog.com/forum/Smileys/default/xtongue.gif.pagespeed.ic.J5mTe0A2NA.png)