Submersed cooling troubleshooting

[chibi_man]

Just looking for a some Do's and Don'ts for submersed cooling.

At the moment i've learned that submersed cooling in oil is very affective and works really well. However i've learned that there are risks involved.

Such as the Capacitors. I've heard that they need to be silconed or sealed in someway. Why? and to what extent do they need to be sealed.

Hard Disk. I've found little information to why not submerse your hard disk... I'm assuming theres a risk that oil can leak inside the harddisk to reach the moving parts. Isn;t a hard disk vacuum sealed, nothing goes in, nothing goes out.

any little bit of information would be great. I'm not looking on doing submeresed cooling. I just want to learn little more about it.

[T-shirt]

submersing in oil is a compromise ~ purefied oils are non-conductive, but only can hold/carry about half the heat of water
I don't know why capacitors would need extra sealing ~ unless the oil washs out or is not chemically compatable with the capacitor.........still it's cheap and easy to coat them, and avoid future trouble

Hard disks are NOT sealed, and definately NOT a vacuum......the heads rely on the air current from the spinning disc to 'fly' just above the surface.
Air is the right density, any fluid getting in through the filtered vent hole would destroy the drive instantly.

[chibi_man]

Far as i know... oil seems to be able to pentrate the capacitors and fry them inside out. thats all i know so far.

I'm surprized to hear that hard disks aren;t vacuum sealed. first thing i was tought was that hard disk were vacuum sealed. oh well.

I'm trying to find a new way to liquid cool a hard disk. I figured i'd use a similar idea to submersed power supplies. Since it seems that hard disk would not do to well in that, i guess i'll have to find another option.

Any wild suggestions?

[T-shirt]

Nope not vacuum sealed, ,but sealed in a dustless cleanroom to prevent a high speed collision.
briefly about floating heads in HDshttp://www.pcguide.com/ref/hdd/op/heads/op_Height.htm

Cooling has to be to the outside of the metal enclosure (or the metal frame on drives with plastic housings) either by forced air (technically, gases are a thin liquid, in movement calaculations) or via a "cold block" (ie a water block) attached to said metal parts.
there a some commerial verisions available
an aluminum or copper block with a heat pipe to move the heat out to an airstream or even a liquid heat exchanger would remove heat from tightly stacked drives.
even if the computer it self was immersed the cables could lead out to air cooled drives (free circulating air cooling should be enough for any consumer level drive, even in a RAID, unless the ambient temps are unusally/uncomfortably HOT or they are enclosed in a poorly ventilated case.