Change permissions

It might be worth trying to change the permissions through your other machine. So when you go to Get Info on the other Mac, add permissions for 'everyone' to read/write. Hopefully it might be as simple as that.

Alternatively, you could check the warp nacelles or eject the core. That usually worked on TNG.

 

I'm not clear on if you need to change permissions. Just in case you haven't done this which results in using the TM UI for access --
Try right-clicking on the TM dock icon, or click on the TM icon in the menu bar and press *option* (or alt) on your keyboard. After doing either, click on Browse Other Backup Disks.

 

You should never manipulate files on a Time Machine volume. OS X has mechanisms to stop you from doing that. If you want to change permissions, then you have to change the source and then let Time Machine record the changes. If you need to import directories or files, then you can use the restore function in the Time Machine application or tmutil and change the permissions as needed. Accessing another device’s Time Machine backup can be accessed as described by rshrugged.

 

As I said, you can restore individual directories or files. Open the Time Machine application, navigate to the directory, right-click -> 'Restore to'.

 

chown takes username:username

go to a dir where you made a file as that user, so you can tell in terminal how it looks normally with ls -all

example:

-rw-r--r--@ 1 floris staff 8520 Jan 23 2016 vbirc_pubcmd.tcl

if you want your file to be like that:

chown floris:staff vbirc_pubcmd.tcl