Re: Multiple Questions

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi CJ,
>
>At 01:10 AM 6/28/2001 -0700, you wrote: 
>Over the past two years I have had quite a few questions about tesla coils 
>but was unable to confirm/deny any information 100%. While I do not think I 
>ever will be able to, tapping the minds of everyone on this list will 
>certinally get me somewhere. 
>Questions
> 
>1) Does the thickness of the wall in the secondary form affect anything? if 
>yes then what and how. (my secondary uses irrigation pipe - very thick 
>walled, about 1/2 inch pvc)

If it is plastic, the effect will be tiny.  Sonotube (cardboard) is a bit
more lossy and you may loose an inch of streamer length.  Nothing to worry
about unless you have a tube coil were the loss may heat the tube noticeably.

> 
>2) Is 85$ for a Maxwell Pulse Capacitor rated at 35kVDC, .030 uF +/- 10%, 
>~2uH E.S.L a good deal
> 
>3) How do you find/become aware of/go to an auction for a power company? 
>(heard they did that)

Call them on the phone and ask around.  They don't advertise these things.
You just have to snoop around and see what they are up to and when.

> 
>4) Where do you find the disc, electrodes, and shaft for a RSG

The disk can be anything from Lexan, G-10, to LE phenolic.  Find a plastics
shop in your area and they can get it for you if they don't already of a
bunch of scrapes they will sell you hopefully cheap.

Electrodes can be brass bolts to tungsten "TUG" welding rod from the
welding supply store.

You can use a standard motor hub with some holes drilled in it for the
rotor to having a machine shop make you something.  I like 1/2 replacement
drill chucks with a mating bolt.

http://hot-streamer-dot-com/TeslaCoils/MyCoils/SmallCoil/small_gap1.jpg

> 
>5) Is it acurate to say that you should have no more than 800 turns on a 
>secondary.

Most people use 800 - 1500 turns with 1000 to 1200 being very common.
There is nothing magical about the number of turns but with all the other
factors, the 1000-1200 range just seems to work out well.

> 
>6) What are the advantages/disadvantages to each type of primary coil. (this 
>one will bring lots of discussion)

Flat coils are common and easy to make.  Cone coils are harder to make but
have better coupling which may or may not help streamer length.  Cone coils
also look better in some people's eyes.  Helical coils are rare in
disruptive coils since they arc over so easily.  They are far more common
(if not the rule) in tube coils.  Unless you have some reason not to, go
with the flat spiral.

> 
>7) What are good prices for NST

Used is free (unknown condition) to $10 (tested and working).  New is 50 to
100 dollars.

> 
>8) Is it worth it to use more than 2 NST's to try and acheive higher current 
>at a much lower voltage?

You want "power".  The actual voltage or current is not super important but
power is.  

> 
>9) I have run my previous coils for less than 30 seconds at a time, many 
>people have horror stories of things breaking, how long do you usually have 
>to run a coil to mess up a NST? (medium sized coil, average components)
> 

If it is not built well it may last only seconds.  If the coil is built
well, it will last indefinitely.  Protection circuits and LTR designs have
dramatically reduced the number of NST failures.  If the voltage does not
go over the NST rating, the current is not greater than 150%, and the NST
is good to start with it will last forever.

http://hot-streamer-dot-com/TeslaCoils/Misc/NSTFilt.jpg

>10) People have referecend neon sign shops many times on websites as being 
>good places to find NSTs cheap, however I have never seen or even heard of a 
>neon sign shop outside of tesla coil sites. I looked in the phone book and 
>found nothing? Do I live in some abnormal area or are they not so common?

They should be under "signs".  Find a bunch of neon signs in your area and
look at them up close for labels indicating who made them.  Big chain
stores have theirs made far away, but local stores will have them made
locally.  Places that make signs for business will make neon signs or know
who does in your area.  In small towns, it might just be someone who works
out of their home by word of mouth.  Call around...  You can also get new
NSTs through the Internet but shipping is high on these heavy iron beasts.
If you tell us where you live there may be other coilers near you that know
the tricks in your area.

> 
>11) I had more...but I didn't write them down at the time, I will post 
>others later, this is all I can think of right now. 
> 
> 
> 
>I do realize that some of these questions are not very scientific, but they 
>are related to Tesla Coils. I apprcieate any answers you have, regardless of 
>your experience. 
> 

Cheers,

	Terry