How to delete unused file parts that are not used in the FCPX timeline? I want to clean up my hard disk and delete large unused GB files on my macbook. In the FCPX timeline I have  several hours of footage cut down into a 3-minute movie, with all short 2-second pieces.

I want to delete the folder with unused long hours files from my disk. How do I save the new short files that I want to keep into a folder?

So the old folder is filled with useless long hour files that I want to delete, and the new folder is filled with short good files that I want to keep.
As you already know you can't easily export just the used parts of your clips. But given FCPX uses XML there must be utilities to do that.

You can get something like clipexporter that will do it automatically.

However you can "share" your final project and then slice that up into shots -- I don't know why you want to do that slicing. AVcutty will slice AVI's automatically (windows OS only).

If disk space is a real problem and you don't mind losing your original footage, just share your final timeline.

Personally I buy an external HDD every two years (whatever $200 gets me) and archive all my personal projects to that. I then copy all the old projects from the old HDD to the new HDD.