Shimming a failed button : Genius Traveller 8000 5 button wireless mouse  - Page 1
Forum section: electronics / repair

author: Ian.M
author_rank: Super Contributor
timestamp: August 02, 2017, 08:43:07 am
content: TLDR: when your favourite mouse gives up, in the spirit of EEVBLOG, take it apart - you may get lucky!Affordable 5 button wireless mice with an on/off switch, suitable for lefties are hard to find (I mouse ambidextrously) so when the heavily used*fifth button which I normally have configured as [Page Down] stopped clicking reliably and became increasingly floppy, it was worth investigating.The button in question is a side button, the rear one of a pair on the left side of the mouse, intended for thumb control. I initially suspected a worn out microswitch, but when I opened it (easy as all four screws are visible after unclipping the top cover to access the battery compartment and USB receiver storage hole), I found that it was a single board design with rocker arm actuators for the fourth and fifth buttons, and the PCB mount microswitches were in good condition, with no significant difference between the action of the two of them.The button (external end of actuator) was partially depressed at rest, without enough remaining travel to fully operate the microswitch. The problem was slop in the actuator arm due to wear at the pivots which are unlubricated journal bearings with the shell formed by the upper and lower case halves. The fifth button actuator is far longer than the fourth button one so is far more sensitive to slop, and it is compounded by the microswitch engaging with the tip of the actuator with a wiping motion, rather than having a L shaped actuator with the side at the end pressing straight down on the microswitch.I determined that shimming between the actuator and the microswitch would be likely to restore normal operation. Due to the very limited surface area of the actuator end and the wiping motion, I decided to glue the shim to the actuator. One drop of superglue and a scrap of cartridge paper later + some careful trimming, I had a fractionally longer actuator. A trial reassembly fond the button much improved but still slightly sloppy, so I applied another layer of paper.Result: Slop gone, and the button is no longer suffering from contact bounce. It took longer to type this up than to fix it.* I useXmouse button controlto assign application specific commands to the extra buttons.

author: MK14
author_rank: Super Contributor
timestamp: August 05, 2017, 02:41:44 am
content: Quote from: Ian.M on August 02, 2017, 08:43:07 amCongratulations on fixing your mouse.They obviously used the mechanical trickery to avoid having multiple PCBs or extra wiring and stuff.Maybe they did not envisage the fifth side button to be used all that frequently. So it was not specified with that long a mechanical key press life expectancy, as the main mouse buttons. Such as left click.I also use XMouseButtonControl. I'm very impressed with how well it is written, how smoothly and seamlessly it works, and its fairly easy to use GUi interface. Its program-ability options are simply amazingly comprehensive.My mouse only has the normal 2 buttons + scroll wheel. But I suddenly REALLY badly needed a few extra switch buttons.While I was researching software to use the extra mouse buttons (I was considering buying a multi-extra button mouse), I discovered XMouseButtonControl. It has let me have the extra buttons, even though I don't actually have them.It is completely free as well!Because it lets you re-map multiple simultaneous button presses as new keyboard key presses. So the (unused by the application) right button, when combined with another mouse button or scroll up or down movement, creates the extra buttons. Amazing and it works really well.The application was mostly fully controllable by mouse, but had this annoying feature, that some things also involved pressing (often continuously) keyboard buttons as well, to do things.Using that utility I can now control it fully from the mouse, which doesn't even have any extra buttons.