tempcos + silicone glue question

[Tony Clark]

   RTV is great stuff, but I'm not sure it is condusive to thermal 
transfer as you are seeking.  I used to have to do conformal coating with 
the stuff at Square D and I was sure they were using it to actually 
_insulate_ the boards.  Not a bad idea to reduce the effects of ambient 
temperature, probably, but certainly not to be used to conduct thermal 
energy.
   However, they whole goal is to just keep the tempco close to the 
expo-converter, adding thermal compound was probably just icing on the 
cake.  I know my OB-X voice boards have no such compound, but the tempcos 
are seated directly over the transistor array.

   Tony
   
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I can't drive (my Moog) 55!         |     The E-Music DIY Archive
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On Sun, 21 Nov 1999, Paul R. Higgins wrote:

> I have a question that I haven't seen addressed during my (short) time on the 
> list; can you use silicone glue/sealant to thermally couple a tempco to an expo 
> transistor or array (e.g. 3046)?  I know that years ago ARP used to goop 
> silicone heatsink compound on their expo circuit and then wrap a thin piece of 
> copper around it to fasten the parts together (and to aid in heat transfer).  
> I'm sure many list members have done the same.  However, heatsink compound is so
> horribly messy, and it really never hardens.  I loathe using the stuff except 
> when absolutely necessary.  
> 
> I got to thinking about using silicone sealant the other day when at the auto 
> parts store (a high-temp version of silicone sealant--I think it's called 
> "RTV"--is used on the head gaskets of engines, etc.).  Will this stuff give 
> adequate thermal conductivity?  If not, what other methods are recommended?  Or 
> do I just  have to deal with goopy, yucky, hard-to-clean-off heatsink compound?
> 
> Thanks,
> -PRH
> 
> _____________________________________________
> Paul Higgins
> email: higg0008 at tc.umn.edu
> University College, University of Minnesota
> _____________________________________________
>