How to delete old time machine backups

How to Delete Individual Backups from Apple Time Machine « Psychohistory

One of those menu items is “Delete Backup”.

So, to delete a full backup, you just do the following:

1. Navigate to the date you want to delete. In my case, I wanted to delete my oldest backup, from 1/30/2008.
2. Navigate in the Finder window to your overall machine. In my case, it’s called “Powersmash G5″, where I have 2 internal drives that are backed up.
3. Select the “Gear” menu, and select “Delete Backup”
4. Enter the admin password for the Finder, if it asks.

My guess is that Apple wasn’t trying to make this hard - they are just suffering from a non-standard interface, and then an overloading of that “gears” menu, which I’m sure is theoretically supposed to be a “contextual menu”. For me, a menu that showed on on right-click of either the finder window itself or the Time Machine backup marker on the right would have been more obvious to me.

Hope this tip is useful to someone. It sure helped me today.