<VV> BLACK DIST CAPS REVISITED

[jvhroberts at aol.com]

 Just fine, MOST of the time, but some do fail, hence the comment about the use of carbon black to hide defects and impurities. If you can't see the flaws, inclusions, etc., then they get out in the field, and it's those that fail. Not all, in fact, not even most caps, but every once in a while, someone gets one with something in the plastic that no one can see, and it's waiting to bite the owner! 

 

John Roberts
 

 

-----Original Message-----
From: Ron <ronh at owt.com>
To: N2VZD at aol.com; virtualvairs at corvair.org; jvhroberts at aol.com
Sent: Sat, Apr 3, 2010 3:29 pm
Subject: Re: <VV> BLACK DIST CAPS REVISITED


The original black caps are obviously just fine, lasting twenty or thirty years with no problems even though most people change them every ten years or so.  At least, that's worked for me. 
RonH 
 
----- Original Message ----- From: <jvhroberts at aol.com> 
To: <N2VZD at aol.com>; <virtualvairs at corvair.org> 
Sent: Saturday, April 03, 2010 12:09 PM 
Subject: Re: <VV> BLACK DIST CAPS REVISITED 
 
> 
> Actually, the black caps DO have carbon black in them, but contrary to > those who say otherwise, the concentration simply isn't high enough to > lower the breakdown voltage of the material. Carbon tracking is due to > flaws and impurities in the material The biggest reason the OE style caps > are black is to hide the flaws! It's THE reason why nearly all materials > have black pigment added to them. Nothing hides defects like carbon black! > Now, things like tires use it as a reinforcing material, but most > applications of carbon black is as simple pigment. 
> 
> For high voltage insulation and structural purposes, there are most > definitely materials out there with fewer chances of breaking down than > what the factory used. It's all about how much they wanted to spend! 
> 
> 
> 
> John Roberts 
> 
> 
> 
> 
> -----Original Message----- 
> From: N2VZD at aol.com 
> To: virtualvairs at corvair.org 
> Sent: Sat, Apr 3, 2010 10:46 am 
> Subject: Re: <VV> BLACK DIST CAPS REVISITED 
> 
> 
> i am not a chemist , but those black caps PROBABLY did not have carbon or 
> conducting materials in them, kinda like bakelite used on high voltage 
> panels  and insulators on electronic equipment since way back..(including > coil 
> towers).  the next best stuff was ceramic and teflon. once the stuff > breaks 
> down due to  moistire , that track WILL measure with an ohm meter. > sometimes , 
> when  conditions are right , there is a mini thunderstorm inside your 
> distributor. too  large a plug gap , weak wires , a loose plug wire with a > gap , 
> 
> will cause the l  voltage to build up enough to wreak havoc in the > strangest 
> ways, not unlike  lightning. 
> i can find out the real composition from guys who know for sure later in 
> the week , if this thread hangs on like most... 
> regards, tim colson 
> _______________________________________________ 
> This message was sent by the VirtualVairs mailing list, all copyrights are > the 
> property 
> of the writer, please attribute properly. For help, > mailto:vv-help at corvair.org 
> This list sponsored by the Corvair Society of America, > http://www.corvair.org/ 
> Post messages to: VirtualVairs at corvair.org 
> Change your options: > http://www.vv.corvair.org/mailman/options/virtualvairs 
> _______________________________________________ 
> 
> 
> _______________________________________________ 
> This message was sent by the VirtualVairs mailing list, all copyrights are > the property 
> of the writer, please attribute properly. For help, > mailto:vv-help at corvair.org 
> This list sponsored by the Corvair Society of America, > http://www.corvair.org/ 
> Post messages to: VirtualVairs at corvair.org 
> Change your options: > http://www.vv.corvair.org/mailman/options/virtualvairs 
> _______________________________________________