[cfraenkel]

FYI - if you make another iteration (or build it into your keyboard), strongly recommend moving the sensor away from directly below the ball. For reasonable ergonomics - you want the top of the ball as close to the desk surface as possible. The 5 ~ 10 mm you need to fit the sensor package makes a big difference. When prototyping the Expert Mouse, we found that offset angles as high as 20 degrees weren't really noticeable, and that allowed the ball to sit just barely clearing the bottom plastic case. (That and use the smaller 51 mm billiard ball instead of the American 2.25" ball)

[mbreese]

Looks like they used an even smaller ball. I didn't know 38mm pool balls were a thing...

> To be able to call this a trackball, we also need some kind of ball or sphere of course. Many people go with the smallest regulation billard balls with a diameter of 38mm.

[xythobuz]

Interesting, I did not think about the possibility of moving the sensor to another position. But it makes sense. The Logitech Trackballs I've seen also have a slight offset that could be in the ballpark of 20 degrees.

I will have to do some further experimentation. Thanks!