On Tue, 5 Feb 2008 04:47:04 -0800, "William Sommerwerck"
wrote:

wrote in message
...
:
: I have a 37-year old H/K Citation 11 preamp. The sliding audio
: equalizers, volume and balance controls are silicone loaded. There is
: a warning label inside the unit that says because they are silicone
: loaded, not to use commercial cleaners on them. Can I use DeoxIT
: D5 to clean them? After 37 years, how much silicone is left in these?
: Any other suggestions?
:
:My guess -- and it's only a guess -- is that the silicone loading is
:"external", not "internal". That is, the silicone lubricant is for the body
f the slider, not for the contact between the slider and the carbon track.
Does that make any sense?) You wouldn't want to get silicone lubricant onto
:the track. *
:

You are correct William. The other nasty about silicone lubricants is that they
tend to "migrate" from where they were originally applied. Since silicone is an
insulator it may have migrated to the tracks and resulted in intermittent
contacts.

Back in the 60-70's silicon gease was used on some moving relay parts in
telephone exchanges. It was discovered that after several months the silicone
had migrated to relay contacts thus insulating them. Silicone lubricants were
henceforth banned in telephone exchanges.

:harman/kardon was worried that the careless application of a commercial
:cleaner would not only clean the track, but flush away the silicone.
:Silicone lubricants are chemically stable, so unless you've repeatedly
:rammed the controls up and down in an adjustment frenzy, most of the
riginal should still be present.
:
:I'd dismantle the unit and look closely at the pots, to see exactly where
:the silicone is, and how best to apply the cleaner to the carbon track
:without hitting the silicone. In other words, I would not squirt cleaner
:into them promiscuously.
:
:I've never used Caig's FaderLube spray, but -- as I like their other
roducts -- I see no reason not to take Chuck's recommendation.
:
:* This is not always the case. Rupert Neve used (and probably still does)
:conductive-plastic tracks. These required the precise application of a small
:amount of lubricant (probably silicone-based -- I don't remember).
: