## Got an email from Roger, K8RI.. re dielectric grease.
It appears that W8JI didnt quite get his story correct.
Silicone grease does not not decompose into Silicon Carbide, It
decomposes into Silicon Dioxide + Hydrogen and/or Chlorine. There is no
Carbon in the grease.
## JI did not use conducto lube either. Conducto lube is 75%
pure silver..and 25% castor oil.
Used in industry + power companies on sliding silver plated surfaces.
Transfer switches typ use several
silver plated fingers in parallel..per phase. Also used on spdt silver
plated knife switches, cut outs,
and fuse holders. Each particle of silver in conducto lube is only
3-4 microns.
## I agree with W8ZR re the use of dielectric grease on coax
connectors. It works good on
both the threads and also the center pin, but only a very tiny bit is
applied, real thin layer.
I have not tried conducto lube on coax pins...yet. I believe it
would work.... but only if used
sparingly. I would only use dielectric grease on threads of coax
connectors. I use 7-16 Dins..
and they can be torqued to 5 x the tq used on SO-239 and type
N connectors.
## I would not use noalox, penetrox on anything but aluminum to
aluminum surfaces, like yagi
eles. Both products are just ground up zinc..in grease.
## copper kote is ground up copper powder..in grease.... used only
on cu to cu surfaces, like
bolted buss bars.
## dielectric grease is a total dead loss if used on NC contacts of
open frame mech relays, JI
mentioned that on qrz / qth.com. He is correct. Typ not enough
spring pressure.
I would not use dielectric grease on contactors..esp if u are
slamming a big load on.
## I did notice that on several of my brand new Deltrol..and also
P+B DPST..and also DPDT 30A
relays, the contact resistance was really high.... and ditto with
poles 1+3 of my 65A 3 pole contactors.
## I tried using a deltrol / P+B 30A DPDT relay for a bypass circuit
in a hb ant tuner. coax to coax type.
It would int go open on RX.... with tuner switched to bypass. My
fix was to apply some cool amp
silver plating compound to the contacts, problems solved, no more int
RX.
## The only other fix was to use a pair of rf chokes, and apply DC
bias to NC contacts. Another
option is to use ceramic vac relays. For hb remote switch boxes, I
use gigavac G2 relays..zero
issues so far.
## I will report back, when I have finished testing.
Jim VE7RF
From: Kim Elmore
Sent: Thursday, January 2, 2020 6:29 PM
To: Tom Hellem
Cc: MU 4CX250B ; Jim Thomson ; amps@contesting.com
Subject: Re: [Amps] Dielectric grease for roller inductors?
See https://www.w8ji.com/dielectric_grease_vs_conductive_grease.htm for the
full treatise. Bottom line is the“conductive” grease refers to its thermal, not
electrical, characteristics.
Kim N5OO
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