Re: primary and secondary diameters and more

From: 	Esondrmn-at-aol-dot-com[SMTP:Esondrmn-at-aol-dot-com]
Sent: 	Wednesday, December 03, 1997 10:25 AM
To: 	tesla-at-pupman-dot-com
Subject: 	Re: primary and secondary diameters and more

In a message dated 97-12-03 02:38:42 EST, you write:

 Thanks for the information!  Here is my current plan:
 I would like to build something with a secondary in the range of 3.5 to 4" 
 diameter, with a neon transformer up to 60ma 12Kv, commercial caps.  I 
 would like to have 12-36" sparks.  As of now I have only a few parts 
 and have started to build the spark gap (easiest parts to find).  I 
 would like to keep the cost down and am currently looking for the 
 transformer and caps.  Should I get these then go from there after 
 I have the voltage and amperage ratings of the transformer?  
 I plan to put the whole primary inside an enclosure made of aluminum and 
 plexiglass.  The secondary will be wound on polyethelyne or PVC tubing, I 
 understand PVC is not as good? The coils will be mounted on top of a 
 plexiglass top to the aluminum box.
 The two sources of information I have at this time (other than the net) 
 are the Tesla Coil book by George Trinkaus and a book that has the plans for
the Information Unlimited coil of similar dimensions.  The coil in the book 
 (BTC3) has the "bundled primary" I guess this is scramble wound?
 Does this sound like it will work so far?  What are the specs of anyone 
 elses successful project of similar size?
 Chris >>


It sounds like you are looking for a project similar to the small coil that I
built earlier this year.  Secondary is 3.0" o.d. winding length 13.0" of #28
wire wound on an acrylic form.  Toroids are 2' x 10" and 2" x 12", made from
styrofoam rings purchased from a crafts shop.  Primary is 14 turns of #10
wire wound flat with .35" spacing between windings.  If you build this
design, I would recommend using 1/4" copper tubing instead of #10 wire.  The
primary form is acrylic.  Capacitor is a home made rolled poly design using
two layers of .062 poly, C = .00475 mfd.  I would suggest a slightly larger
cap, maybe around .006 or .008 mfd.  This coil tunes right at turn # 14 on
the primary.  Gaps are the RQ cylindrical gap using 6 gaps set at .028" each.
 Power is two 12 kv 30 ma neons.  I have two 3,000 ohm 25 watt resistors in
series with each HV supply lead and a safety gap mounted at the transformer.
 This coil produces about 18" discharges but would do better with a better
primary and a little larger cap.

You should not mount the primary on an aluminum box.  It should be 12" to 24"
above any metal surface.

Ed Sonderman