Tip: Mouse scroll wheel speed

[jg3]

I spent a while looking for this on the web last night and didn't find anything, but discovered a (potential) solution thanks to my G5 at work...

My Macally iOptiJr (which is a great mouse), came with supplementary drivers that allow you to set the scroll wheel speed, and what event gets triggered when you click the right button and scroll button, the latter settings on a per-application basis. This is nice, but I wasn't making much use of it, and it prevented me from using the buttons for Exposé, something I've gotten used to at work.

So I removed the Macally drivers, rebooted, and then was able to hook up the buttons to Exposé. However, I was stuck with the default scroll wheel speed (read: slow), and no way to adjust it. I scoured the web, but only found tips on how to change the mouse tracking to be faster than System Preferences allows via its UI, for example:

defaults write -globalDomain com.apple.mouse.scaling -float 5.0

followed by logging out and back in again. So that's great, but not what I needed.

At work today, I remembered that I was looking for a solution, and on a whim looked up defaults:

defaults read -globalDomain

and discovered this line:

"com.apple.scrollwheel.scaling" = 0.5;

So... when I go home, I'm going to try setting that value, logging out and back in, and see what happens! Who knows why System Preferences on my home machine doesn't give me the bar to adjust it (I do get the bar on my work machine), but hopefully this will work - and hopefully it will save someone here from wasting money on a shareware utility to do this!

 

[jg3]

Update

OK, I was excited to try this out at home, so I typed:

defaults write -globalDomain com.apple.scrollwheel.scaling -float .8

The default was saved properly; cool. Opening the Mouse prefs didn't show anything new, but that's alright. I logged out and back in, opened a long browser window and... still slow scrolling. :\ Then I realized that what was probably going on was that the mouse driver was doing its own scrolling thing, rather than working through the OS's system, meaning that the core driver would have to go as well. (What I removed before was apparently just the UI to configure the driver's settings.) So anyway, here's what I did to actually get it to work:

First, I unloaded the driver kext:

sudo kextunload /System/Library/Extensions/MacallyMouse.kext

Then I deleted it (you can move it somewhere else if you'd rather keep it for backup):

sudo rm /System/Library/Extensions/MacallyMouse.kext

Then my mouse stopped working. But all I had to do was unplug it, wait a second, and plug it back in. It started working again all on its own, and was using OS X's built in drivers, so when I went to the mouse prefs, I got the scroll wheel speed adjustment! Finally!