How do you set custom time limits in Mac OSX? I'm searching for a custom method to limit access to our mac. Parental controls allow you to limit time by school nights and weekend time chunks through system preferences. However, I want more options for the limiting. For example, on Mondays I want access available from 2pm to 5pm and then again from 8pm to 10pm limited to 2 hours total login time. Tuesdays may get different time ranges and total access time.

It seems like I should be able to do this by modifying the com.apple.familycontrols.timelimits.v2.plist file. But it gets rewritten back to the settings I have previously set through system preferences.

I don't want to use a 3rd party software for this. It seems that I should be able to accomplish what I want by manipulating settings "under the hood". Any ideas on how I might do this?
I would use the Automator application and set it there with Calendar events.

All you have to do is crate different events (shut down times and dates).

Example: