Can I store a CWM backup on the PC and copy it to the phone when needed? I was wondering if I could just simply copy the backup file and when needed copy back to the phone....because it takes up almost 3 G space. Weird that it is that big.

By the way....I cant even locate the backupfile. Where is the default folder for it?
Can I store a CWM backup on the PC and copy it to the phone when
  needed?


Yes, you can.


  CWM backups are stored in /data/media/clockworkmod/backups


And for TWRP :


  you can choose the files/backup-files for saved and stored in Sdcard or Extsdcard
  during backup process.


Stored in -&gt; sdcard -&gt; TWRP -&gt; Backups


or:       Extsdcard -&gt; TWRP -&gt; Backups

and then, you can copy this backup when needed into the phone and then,
Restore it from related recovery.