I had a situation that the mouse ball worked in 3 directions: left, right, down, but not up.
When moving finger up, the ball did not rotate under finger. So I could only use external mouse.
I wanted to fix this.
First I had to open the deveterm and take out the keyboard.
Then unscrew all 23 (if I counted correctly) screws on the keyboard.
To remove the PCB.
Then the mechanical part of the mouse device was finally free.
I took it out.
Top plastic part and bottom plastic part held together with thin metal part.
Ball is inside.
With a tiny metal knive I very carefully unattached the metal part from the plasic one without damaging anything.
With this I could take out the ball and the 4 rolling things.
There was a lot of dirt inside. I cleaned it as good as I could and then reassembled everything again.
Important to insert the 4 rolling things in the same orientation. It is possible to insert them in opposite, which would result in mouse movement rotated by 90 degrees, I think.
Now the mouse works again in all directions but still it doesn’t “feel” just as well as when it was new.
I wonder if others also had a similar experience with having to clean a stuck mouse.
In normal mouses with a rolling ball it is usually easy to open it, take out the ball and clean.
Here, I don’t see an easy way which doesn’t require so much inconvenient disassembly.