Upload Permissions Ubuntu Server?

Hi all,

I have a server set up that I can SSH into just fine - both locally and remotely. However, when I try to manage the server via FTP, some things go wrong. Most files I am able to put and get just fine. The problem arises when I mount an external hard drive to home/username/storage/HD1 (a folder I created). The drive mounts just fine and I can get any file from it. However, when I attempt to put files, I keep getting permission denied errors. I have attempted chmod to give all users and groups rwx access to HD! and its contents, but that is denied - even if I try to make this edit after sudo -s to act as root. I'm stuck as to how I enable uploading to my mounted drive. Any resources or help is much appreciated.

Thanks so much.