In message tonline,
Roy Lewallen writes




And, when tightened threads *are* necessary for electrical contact, oil
or light grease often improves conductivity. Thread pressure is
adequate to squeeze the lubricant out from the contact areas, allowing
good metallic contact. And it prevents oxidation or other corrosion of
the contact surfaces when the contacts are moved or vibrate by
excluding air. This holds true for all contacts properly designed to
wipe and contact with sufficient pressure. Quite a few people
incorrectly attribute this improvement to conductivity or some mystical
property of the lubricant, but its real trick is simply to exclude air.

Roy Lewallen, W7EL

I would be surprised if a lubricant was sufficiently viscous and had
enough 'body' to act as an insulating layer between two parts of
well-tightened a connector.

However, I have personal experience that Araldite can. This was used to
ensure that a reducing bush (PG11 thread to 5/8"), in the wall of the
housing of a CATV amplifier, remained securely in place. On all four
ports, there was absolutely no continuity between the outers of the
connectors and the housing.
--
Ian

Ian Jackson wrote:

I would be surprised if a lubricant was sufficiently viscous and had
enough 'body' to act as an insulating layer between two parts of
well-tightened a connector.

However, I have personal experience that Araldite can. This was used to
ensure that a reducing bush (PG11 thread to 5/8"), in the wall of the
housing of a CATV amplifier, remained securely in place. On all four
ports, there was absolutely no continuity between the outers of the
connectors and the housing.

Araldite seems to be a trade name for a variety of adhesives. There are
certainly materials other than the oil or light grease I was speaking of
which will interfere with continuity, and some of those adhesives are
apparently in that category. Kids, don't apply epoxy to your relay
contacts. Honey and contact cement might not be too good either.

Roy Lewallen, W7EL

"Roy Lewallen" wrote in message
treetonline...
Ian Jackson wrote:

I would be surprised if a lubricant was sufficiently viscous and had
enough 'body' to act as an insulating layer between two parts of
well-tightened a connector.

However, I have personal experience that Araldite can. This was used to
ensure that a reducing bush (PG11 thread to 5/8"), in the wall of the
housing of a CATV amplifier, remained securely in place. On all four
ports, there was absolutely no continuity between the outers of the
connectors and the housing.

Araldite seems to be a trade name for a variety of adhesives. There are
certainly materials other than the oil or light grease I was speaking of
which will interfere with continuity, and some of those adhesives are
apparently in that category. Kids, don't apply epoxy to your relay
contacts. Honey and contact cement might not be too good either.

Roy Lewallen, W7EL

I used to think that too. Good point about the inner shell, but I wonder if
all N's are created equal. That might have tainted my results. The
experiment was encountered in the process of tuning cavities, duplexers and
other filters with a R2001D. I have used oils before but some will rot the
gasketting. Grease or oils will migrate, but Stainless is a problem about
galling. It was a regular thing to have to clean Silver dust and grunge
from the bulkhead female with a q-tip and Isopropyl. The final answer was
to add a sacrificial N male to female adapter to save wear on the Silver
plating.

I also noticed Coffee doesn't make good contact cleaner either. Even with
plenty of sugar (just trying to help).