[Boatanchors] Broken tube cap repairs

[Bill Abate]

  Brian,

The manufacturer is Permatex.  The product is Ultra Copper Gasket Maker. 
  It is actually rated at 700 degrees F, intermittent.

73,

Bill, K3PGB

Brian Clarke wrote:
> Hi Bill,
>  
> Interesting! What is the maker and type number of your RTV compound?
>  
> RTV products are usually made from rubber or silicone - which degrades at
> such elevated temperatures as 700 - whether C or F. RTV means Room
> Temperature Vulcanising.
>  
> This high temperature RTV product you have would have to be for exhaust 
> gaskets
> - head gaskets should not exceed 120 C, or about 250 F. Anyway, the top 
> of an
> electron tube should not exceed a bulb temperature of about 400 F - if 
> it gets to
> 600 F the solder will reflow.
>  
> 73 de Brian, VK2GCE.
>  
> 
>     Bill said:
>      AS it turned out I had a tube of high
>     temperature RTV for enginge gasklets.  Its good to 700 degrees.