What's the brand of the hard drive ? If it's still spinning up but the heads are locked in the parked position it often can be fixed.
You need to open the drive's housing in a dust-free environment and remove the parking mechanism of the heads.
I had good luck with Connor and IBM drives, regrettably not with Quantum models.
if you have spare dead hard drives, open one up and give it trial. There's nothing too loose anyway if the drives aren't working anymore.
Nico