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Question about Primary Inner Diameter

Original poster: "Bill Vanyo by way of Terry Fritz <twftesla-at-qwest-dot-net>" <vanyo-at-echoes-dot-net>

I just built a new primary for my new (first) coil.  I'll explain why

Due to the way I constructed it, I couldn't precisely control the inner
diameter.  Now I have a secondary with 6 5/8" diameter, and the primary
inner diameter is about  8 1/8" (whereas it was previously 9.5").  Will
this be work?  I'm using three 15/60's as power, and want to add a
fourth (if that's relevant).

Will it help if I raise the secondary somewhat?  Structurally, what
works best (easiest) is for the lowest turn of the secondary to be about
1.25" above the top of the primary.  I could lower it a bit.  I will
also have a plexiglass sheet over the primary, below the level of the
bottom turn on the secondary (again, if that's relevant).

	Thanks again,
	Bill Vanyo


For the curious --- Why I rebuilt the primary, and how (in such a way
that I couldn't get the exact inner diameter I wanted):

First, my coil worked pretty well, but it was heavy as hell (with
secondary removed, and no power supply) - a 19 turn primary on a heavy
home-made deck, with space underneath that was originally going to
contain the power supply.  Most of the weight was wood.  As I grew power
hungry (adding more NST's), the power supply came to require a seperate
cart, and the primary and supporting deck didn't need to be so big
(primary tapped between 5.8 and 7 turns, depending on toroid).  So I
decided to rebuild, for portability (I can only run it outdoors).

Now, as for how I constructed it: The primary supports are 8 pieces of
6" square, 1/2" thick HDPE (cutting board), with 11 holes drilled in
them.  These are UNCUT.  That is, the tubing passes through the holes -
it is not laid in notches with something holding it down.  It's quite
beautiful, but it was a bitch to construct.  Basically, I wound the coil
on a big board with pegs in it (arranged like eight radial spokes, pegs
spaced 1/2"), then slid the HDPE supports around the coil, turn by
turn.  This sliding caused some sort of shifting that resulted in a
smaller diameter than intended.  Perhaps I'll make another, with the
diameter larger to start, so as to compensate.  But the end result is
nice - the coil is essentially embedded in the eith supports, and quite