RE: spark gap/ primary coil

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Rich" <rdjmgmt@xxxxxxxxxx>

It may not be the best but what I use is a split bolt wire connector ,
you can get the to fit 1/8 ,3/16, 1/4 or what ever size you want, Home
Depot/ Lowe's has then up to about 3/4".

Rich

Subject: Re: spark gap/ primary coil

Original poster: Just Justin <rocketfuel@xxxxxxxxxxxxx>


On the subject of 1/4" copper tubing, I wonder if any here have
recommendations for a good moveable clamp that fits the 1/4" tube
well?  My current clamp has some steel in it and tends to get
a bit too hot to touch after just a little while ;)

Justin




On Wed, Feb 22, 2006 at 09:47:59AM -0700, Tesla list wrote:
 > Original poster: "David Rieben" <drieben@xxxxxxxxxxxxxxx>
 >
 > Hi Michael,
 >
 > Welcome to the list and to coiling ;^) First of all, you are NOT
 > going to be delveloping 6000 kV (that's 6 megavolts!) with your
 > coil nor is anyone else on this list for that matter! 600 kV would
 > be a closer guestimate although that's still probably high by a fac-
 > tor of 2 or 3 for an average sized NST driven, spark gap coil.
 > The alternating currents in the tens or hundreds of kHz can pro-
 > duce spark lengths vs voltage that are much higher than the
 > standard DC sphere spark vs voltage rating.
 >
 > The 1/4" copper tubing should not be that expensive at your
 > local home improvement store's (Home Depot or Lowes) plumb-
 > ing department. I would think that you should be able to obtain
 > (2) 50 ft rolls of it for under $50. I think most knowlegable coil-
 > ers are going to tell you that coax cable is NOT a good choice
 > for the primary coil conductor. In operation, it will carry some
 > very high peak currents (in the hundreds of amps) and the fine
 > outer braiding of standard coax cable is not suitable for carrying
 > these immense currents. OTOH, copper tubing is indeed well
 > suited for this purpose and is the usual conductor of choice for
 > most coilers' primary coils. Also, as you said, the bare copper
 > tubing renders multiple tuning much simper than with insulated
 > wire.
 >
 > Good luck with your coil,
 > David Rieben
 >
 > ----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
 > To: <tesla@xxxxxxxxxx>
 > Sent: Wednesday, February 22, 2006 8:57 AM
 > Subject: spark gap/ primary coil
 >
 >
 > >Original poster: "Michael Ong" <omenowner725@xxxxxxxxxxx>
 > >hello, i am planing to use a TCBOR style spark gap but was wondering
 > >what the advantage was of having it in the circular PVC pipe instead
 > >of just a flat sheet of plastic with large fans blowing across it.
 > >it seems like construction would be difficult to get the spacing
 > >correct inside a tube like that. also, my coil is going to be a
 > >6000kv  with a secondary of 4.25" diameter  1700 30 awg wire (22
 > >inches tall) for the pirmary using 1/4" copper tubing 1/4" spacing
 > >in a flat spiral my java tc simulations say that i will need about
 > >52 feet of copper (18 turns). I dont think i want to spend the $100+
 > >on just the pirmary so i am thinking about going with coax cable. my
 > >question then is: is there a way to adjust the pirmary easily using
 > >coax? or is the easy shorting clip used on the copper tubing the
 > >reason why most use that?
 > >thanks again for all your help, its really getting me through my
 > >first tesla coil experience.
 > >_
 >
 >