[ARC5] on sticking coil windings together - Re: My 10 meterBC-454...

[Richard Knoppow]

----- Original Message ----- 
From: "John Hutchins" <jphutch60bj at gmail.com>
To: <arc5 at mailman.qth.net>
Sent: Thursday, January 24, 2013 4:16 AM
Subject: [ARC5] on sticking coil windings together - Re: My 
10 meterBC-454...


> Group
> Subject on sticking coil windings together.  E6000 sewing 
> glue, yep that is the one.  Look it up some one did some 
> home analysts and found that this glue had little effect, 
> in degrading a coils Q better than varnish, better than 
> many materials .
>
> www.qsl.net/k5bcq/COIL/COIL.html
>
> With all that cold -50 below weather up north that would 
> have been a great opportunity to test in extreme cold for 
> free! to see it the low temperature had any effect using 2 
> coils of known inductance, one free air and one wrapped 
> and glued.  I know in -50 below I would change Q in a 
> hurry.
> Later
> Hutch

      You can make real Q-Dope easily. It has very low loss. 
I don't know the dielectric constant but you can look it up 
because its composed of polystyrene.
      It is made by dissolving polyfoam in MEK or Xylol. I 
find MEK works best. I made mine from what styrofoam cups. 
Cups seem to be pure polystyrene.  Crumble the plastic and 
dissolve it in the solvent. It will dissolve quite rapidly 
at first then more slowly as the solvent begins to become 
saturated.  I made mine about the consistency of honey. It 
may take a couple of days to get it to this thickness.
      The resulting material will be clear although it may 
take some time for a slight cloudiness to disappear. Use a 
glass container and make sure its cap won't dissolve in the 
solvent.  I tested this stuff on some home made high-Q coils 
on a Boonton Q-Meter at frequencies up to 250 mhz and found 
it made no difference in the inductance or Q of the coils. 
It sets in perhaps fifteen minutes and hardens in a couple 
of hours.
     Q-Dope is still made but not carried by many places.
     MEK and Xylene/Xylol are available at any hardware or 
paint store.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com