ultrasonic cleaning for disk heads

[Curious Marc]

> On Jan 27, 2018, at 11:02 AM, Mark J. Blair via cctalk <cctalk at classiccmp.org> wrote:
> 
> When it happens, am I correct in assuming that the pack is toast, and should never be loaded again?

Carl would be better qualified to answer that one, but from what he has taught me and what we've seen so far, it depends. If it's a mild crash and just burnished, it might be OK. A lot of the PARC packs we read had such leftover marks from previous mild encounters with a head... Some read just fine, most dirtied our heads but were OK at least for archiving once, a few re-crashed. If there is a gouge and you can see the metal, forget it.

Marc