Core memory is woven with insulated wire.  Dust should NOT be a factor.
There are some nasty dust-bunnies living in some of my core stacks, and the
core seems to like it that way.  If its not broken, don't fix it!
"Jeffrey S. Sharp" wrote:
    G616.  Holding the board up to light and peering into
the space
 between the two boards, I can see quite a few dust clumps. 
 And this might effect the operation how? 
 
 Who knows... There's no telling what's actually *in* those clumps.  I know
 nothing of the environment(s?) in which the machine was stored.  It's
 possible that there could be something conductive in there.
 --
 Jeffrey S. Sharp
 jss(a)subatomix.com