Hello ssacrist,
It sounds like you have copied the backup files to your internal hard drive and would like to transfer them to a new external drive. I recommend the steps in the following article which may work, but is for copying the backup files from the original backup drive to a new one directly:
Time Machine: How to transfer backups from the current backup drive to a new backup drive
http://support.apple.com/kb/ht5096
To have the existing Time Machine backups on the new backup drive, follow these steps:
- Connect the new backup drive to your Mac.
- Open Disk Utility (located in the Utilities folder).
- In Disk Utility, select the new drive's icon, then make sure it has a GUID partition, and is formatted as Mac OS Extended (Journaled), which you can check on the "Format:" line at the bottom of the window.
- If it is not formatted as Mac OS Extended (Journaled), reformat the drive as Mac OS Extended (Journaled) with a GUID partition. If you do not know how, see the steps in this article. Note: Back up any important data on the drive before you format it.
- Open a new Finder window. In the Finder sidebar, click the icon of the new backup drive and choose Get Infofrom the File menu or press Command-I (⌘-I)
- Make sure "Ignore ownership on this volume" at the bottom of the "Sharing & Permissions:" section is not checked.
- Open the Time Machine pane in System Preferences. Choose Time Machine > Open Time Machine Preferences…
- Slide the Time Machine switch to Off.
- Open a new Finder window. In the Finder sidebar, click the icon of the current backup drive.
- Open a new Finder window. In the Finder sidebar, click the icon of the new backup drive.
- Drag the folder "Backups.backupdb" on the current backup drive to the root level of the new backup drive.
Note: If the drive is formatted as Mac OS Extended but without journaling, OS X may state that "the volume has the wrong case sensitivity" to be used as a back up disk.
- Enter an administrator name and password, then click OK to start the copying process. This may take some time to complete because all the backups will be copied.
- After the copy has completed, open Time Machine preferences and click "Select Disk…".
- Select the new backup drive, then click "Use Backup Disk".
Thank you for using Apple Support Communities.
Take care,
Sterling