Re: Best Sec. form material

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

Original poster: "Dr. Resonance by way of Terry Fritz <teslalist-at-qwest-dot-net>" <resonance-at-jvlnet-dot-com>


We use 1/8th wall fiberglass tube for all our coilforms.  We sand inside and
outside of the tube and then coat with 3 coats of red Glyptal.  Overnight
drying between each coat.

If it's a magnet wire coil use Dolph's AC-43 (much better than polys because
it's especially formulated for the transformer industry especially for this
application.  Urethanes will sometimes crack due to temp changes.

If it's a 3 kV PVC wire (larger coils) then use a single coat of clear
Glyptal.  Not multiple coats because it will look yellowish.

Dr. Resonance

Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo   WI   53913
 >
 > Say for an 8 or 10 inch coil (that might run at a lower frequency),  how
 > does the losses of sonotub compare to, say, acrylic (plexiglass).
 >
 > Are there meaningful differences in sealants suchas shellac, spar varnish,
 > polyurythene,
 > etc?   ...and what about overcoats on the winding or should one stick to
 > polyurythene.
 >
 > Should the inside of the sonotub be coated (somehow) to keep moisture out?
 >
 > Speaking of losses,  is a wood frame for holding copper tubing for the
 > primary a bad idea or would it be OK if baked and sealed with varnish.
 >
 > Gerry
 >
 >
 >
 >  > Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>"
 > <dhmccauley-at-spacecatlighting-dot-com>
 >  >
 >  >
 >  > Sonotube is an excellent choice and works extremely well.  It sounds to
me
 >  > that you didn't precoat your sonotube prior to winding.
 >  > Orange shellac is an excellent sealant for this.
 >  >
 >  > The Captain
 >
 >