Backup Exec - Duplicate Old Tapes to New Tapes with single tape drive... and usb disk based folder

I have to take some old backup tapes that we still have around and duplicate those for storage.

After thinking this would be a simple process I've run in to a few hickups that I hope to get some advise on.

I have an Autoloader but its just a one tape writing drive, the other slots are just for storage so that means I need to duplicate the tape to disk... and then from disk to a new tape.

Because these are old tapes in an non-functional backup process I'm assuming I'll need to load them, then catalog them.

Then I'll create a USB disk folder (since the server itself doesn't have enough disk space to house the full tape).

I'll then use the duplicate job function to find the newly catalog'd tape and point it to the USB disk folder.

As a side question when created the USB disk folder there's a question about the size of the files. Can I just leave that at the default?

Here's where I'm stuck.

How do I get that job that's now on the USB folder as a series of multiple files on to a new tape?

I'd appreciate any input you can provide.

Thanks!