Re: Coat the secondary or not?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com> 


Yes, you should seal the coil.  The varnish will prevent flashover and helps
avoid RF tracking across the surface.  Coilform should be sealed prior to
winding with 2 coats.  After winding 3-4 coats works good.

If you don't seal the coil your coilform, it could react to temp and someday
the coil will come loose --- a real mess.

Best material to use is Dolph's AC-43 varnish (use websearch --- they have a
site).  It is especially formulated to seal and prevent uncoiling of magnet
wire.  Don't use polyurethane --- it will crack with time and temp changes.

Dr. Resonance

 >
 > I've read several opinions on whether or not you should coat the
 > secondary with some sort of sealant/protectant (e.g. polyurethane,
 > epoxy, etc.).  The pluses are that the coil is well-protected, and
 > possibly more attractive (depending on your feelings about what
 > looks good).  The minuses are that if you coat the coil, you can't
 > really get at it in case something goes wrong.
 >
 > What are the current opinions, for and against?  When would you
 > want to have access to the windings, and when would it not matter?
 >
 > Michael Johnson
 >
 >
 >