Mountain Lion spins down my external disks (how to, work, Mac)

[amylewis]

I'd like to keep my USB external drives spun up, but Mountain Lion keeps spinning them down after some period of time, perhaps 30 min. It used to be with Leopard I could turn that off in the power saving option, but not any more. There seems no way to get the OS to just leave them spun up. I don't care for having to wait for the disk to spin up to access files on it.

Anyone know how to do this in Mountain Lion?

[tobiasra]

I own a PC with external disks that unfortunately have the "shut down" embedded in firmware (i.e. no activity in five minutes = disk spins down). It cannot be turned off. However, I worked it around with a tool which writes and deletes a small dummy file to the drive every minute. It's called HDKeepAlive. Perhaps something similar exists in the Mac world.

[amylewis]

Aha! so, it's not my OS that's doing it after all. Well then, I shall see if I can't find something like you mentioned. Thank you

[Sayantsi]

Keep Drive Spinning for Mac | MacUpdate

Basically what was described above - keep the disk going so you don't get the spin up delays.

My only advice - get SSD if you can afford the capacity you need!