Alright, looks like the default is 10mins before osx will put it to sleep. Of course when I'm testing it 10 mins seems like forever.
I just found this article which lets you modify it.
http://reviews.cnet.com/8301-13727_7-10346924-263.html
I just set it to 1 min and the hdd is quiet and my whole laptop is solid state (except for the fans).
Now, that article says between 3-5mins.
If anyone else has done this, what have you set yours to if any.
My second hdd, holds my lightroom, itunes really.