RE: secondary question

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Lau, Gary" <Gary.Lau@xxxxxx>


Hi Drake:

Comments interspersed...

> Original poster: "Drake Schutt" <drake89@xxxxxxxxx>
>
> hey all,
>
> I've now assembled most of the materials I need to build my first
> tesla coil.  I used teslamap57 to design it, and ive never heard of
> anyone on-list using this.  Is it accurate and reliable?  I am going
> to wind about 1000 turns of 26awg wire on 3.5 OD pvc pipe.  the only
> problem is that it is pretty thick-walled and its called like
> cellcore or something like that, basically insulated i guess.  Will
> this cause problems?

If the pipe is black, I would worry.  But I don't think the presence of
air or closed-cell foam by itself is a concern.

> Also, will it enhance the performace of my
> soon-to-be coil if i clean, sand, and coat my secondary form before i
> start winding it?

It depends on who you ask ;-)  It definitely won't make your sparks any
longer.  Some believe that meticulous form preparation will make it less
susceptible to racing sparks and other calamities.  But I think most of
us just coat the windings with polyurethane after its wound, simply to
keep the windings from shifting and to afford some degree of abrasion
protection, and for aesthetics.

> Also, if my secondary has an OD of 3.5in, then
> what should the diameter of the hole in the primary be?

A 1 inch clearance between the pri & sec is more than ample, so a 5.5"
primary ID is good.

> any help appreciated as always
> -dr. drake
>
> specs:
> 12/30nst
> cap=9.3nf@32kv
> seconday(hopefully) 17inx3.5in=999 turns of 26awg

Regards, Gary Lau
MA, USA