Heat sink compound vs. dielectric

[Clarence Wood]

  I found a tube of silicone dielectric compound (notice I learned how to spell it!) at NAPA: ECHLIN ML-3 contains dimethylpolysiloxane, $10.95 for 1 oz.  

At 03:23 PM 1/9/99 -0500, you wrote:
>Roger Heflin wrote:
>> 
>> On Sat, 9 Jan 1999, Clarence Wood wrote:
>> 
>> >   A salesperson at AutoZone tried to sell me some heat sink
>> >   compound stating that it was a dialectic.  Of course I challenged
>> >  the statement and he told me that he had used heat sink compound to
>> >  insure good connections.
>> >   Is heat sink compound a dialectic?  Curious minds want to know!
>> 
>> A diaelectric is an insulator.  It does not maintain a good
>> connection, that is the whole idea.  Using heat sink compound to
>> insure a good connection would be really bad.  Most heat sinks the
>> case is ground and you want it to have a good connection with ground,
>> dielectric is supposed to not maintain a good connection.  Of course
>> if most of the people he was selling it to are using it in the spark
>> plug boots I really don't see it making that much of a difference.  In
>> the books I have the insulating material in a capacitor is called a
>> dielectric so that would lead me to believe that dielectric grease was
>> non-conduction.
>> 
>>                         Roger
>What you want is electrically neutral. A conductor would cause shorts
>between connectors in a plug. The ideal is an insulator that displaces
>easily from pressure points - like connector fingers/pins, sealing air 
>and moisture from the connectors. A good dialectric or heat sink
>compound meets this requirement, unless you are working with very low
>current/low voltage signals where specialized stuff like the Stab22 is
>required.
>Do NOT use RTV silicone, as it produced Acetic acid as it cures (hense
>the vinegar smell) which will (or can) corrode connections.
>
>