External Hard Drives

We have seen postings here from people who did what you are asking about and ended up losing those other non-Time Machine files that were on the same disk when Time Machine needed the space. You could partition the external drive to create two separate volumes and then Time Machine will not overwrite the other miscellaneous files if they are on a separate volume. But then if the drive fails (they all do eventually) you will lose the backups AND those other files. Better to dedicate the entire drive to Time Machine as suggested by tbirdvet.

pavlov77 wrote:

I've used 2 external hard drives - one for Time Machine and a second for some large file fotos that aren't kept on my computer and thus not included in Time Machine.

You can back them up with Time Machine. Make sure it isn’t excluded in Time Machine system preferences.

I do not recommend you put other files on your TM backup drive. That should be dedicated to backups only especially using Monterey.