Re: I give up!! I regret building my tesla coil!

["brian foley" <ka1bbg1-at-mcttelecom-dot-com> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, August 21, 2000 8:58 AM
Subject: Re: I give up!! I regret building my tesla coil!


> Original poster: "Jim Lux" <jimlux-at-jpl.nasa.gov>
>
> First off...
>
> 1) Never believe the advertising with respect to spark length (just like
> MPG, your mileage may vary, and will usually be less). Coiling is
> frustrating... there are so many things that affect the spark length, and
> most of them interact.  Be happy with 1" at first, and then gradually make
> it longer.
>
> 2) The only homemade cap that I'd fool with is a beer bottle cap.  For the
> hassle, any sort of poly/aluminum foil version is stomped into the ground
> by a MMC.  For quick and dirty, get it working... get some transmitting
> doorknobs. Sure, they aren't the best, but they DO work, and they are
> readily available, and easy to connect to.  If you are truly poverty
> stricken (like your budget is < $25, and you have lots of time to
> scrounge), the beer bottle (or wine bottle or whatever) is the way to go:
> salt, aluminum foil, and cooking oil are awfully cheap (if not free).
>
> All coiling (or maybe everything) is a tradeoff.... The cool, slick,
> compact system isn't going to be cheap.  Cheap is generally bulky, heavy,
> fragile, or clunky (or all of the above).
>
> This all said, it is possible to easily get 12 inch sparks from a 15 kV/30
> mA neon transformer ($80 brand new retail, much much less used or
> scrounged), a pair of 2700 pF, 40kV doorknobs (about $25 each at an
> "expensive" surplus place), bare #14 AWG house wire for the primary, 3
> pieces of 1" copper tubing 2" long as a spark gap, and a secondary wound
on
> a 3" cardboard mailing tube with #21 enameled wire, and a toroid made with
> 4" flex dryer vent tubing and two pie pans. No chokes, but the wiring is
> short, and the gap is across the NST, so I figure the gap shunts all the
> RF. It may not be fancy, but it works.  You'll need a few scraps of
plywood
> to hold everything, and some sort of insulating standoffs to hold things
> like the spark gap.
>
> It shouldn't  take more than 8 hours to put it together, starting with all
> the parts lying on the table in front of you until you get "first light",
> which will be sparks a few inches long to a grounded rod. Then, you'll
> spend the rest of your life trying to make them longer...
>
> ----------
> > From: Tesla list <tesla-at-pupman-dot-com>
> > To: tesla-at-pupman-dot-com
> > Subject: I give up!! I regret building my tesla coil!
> > Date: Sunday, August 20, 2000 6:52 PM
> >
> > Original poster: "Garry F." <garryfre-at-pacbell-dot-net>
> >
> > I have built tesla coils when I was in high school, in college and
> recently. My
> > biggest problem was a continual burning out of the NST over and over
> because I
> > could never understand the hieroglyphics that were presented to me
> instead of
> > plain english as to how to build a choke to prevent feedback.
> >
> > Finally I get some plans from
> <http://www.sciencefirst-dot-com>www.sciencefirst-dot-com
> > and I build according to their plans and it was supposed to produce 18"
> sparks
> > but produced only one and a half inch sparks. The plate stack cap plans
> were
> > defective, the dimensions of the coil was 1.5" by 40! This is the WOUND
> area!
> >
> > By fooling with it I eventually got sparks near 8" but the toriod had no
> break
> > out at all. Well, being broke from buying a brand new NST for this and
> tools, I
> > had to wait some weeks before I had some more money to spend (Waste).
> >
> > So, I spend more money and make another secondary and this turns out to
> be 3"
> > by 24" using #29 magnet wire. Better, but not short enough. Still it
> produced
> > nice 12" sparks easily. I am using a 9kv .2 MA NST and produced 14"
> streamers
> > off the toroid..
> >
> > Ever being interested in improving the output, I tried various spark gap
> > designs. One suggestion was use two rounded brass doorknobs in an air
> cooled
> > system. The results were abysmal! Lousy 1" streamers off the toroid that
> were
> > so sporatic, I could eat a sandwich between streamer appearances.
> >
> > I built a spark gap that was made of aluminum flashing rooled up at the
> ends to
> > provide a make shift cooling fin design. This worked pretty well.
> >
> > Then I stated my design here and they said I almost had a Push-Pull
> circuit and
> > I could have a true push-pull circuit if I added a grounded electrode in
> my
> > spark gap letting both branches spark into this. I tried this. The
> results were
> > again dismal. I tried retuning. It was HALF the output I had from the
> previous
> > design.
> >
> > Then I tried that J. Quick spark gap design and the output from that was
> even
> > worse!!
> >
> > So, I try to revert back to my rolled flashing air cooled design and no
> matter
> > how much I fiddled, I did not get quite the output I had before I tried
> the
> > push-pull thing.
> >
> > Then I heard that the electrodes should be absolutely flat and so I
built
> one
> > Thursday night and it was producing better sparks. Not like what I had
> before I
> > tore it apart for the push-pull design, but close.
> >
> > The next morning, the spark gap would not fire reliably, so I took it
> apart and
> > adjusted the gap smaller and I got lousy output of 2" streamers off the
> toroid.
> >
> > So, I buy some 1/4" refrigeration tubing and try another primary. It's
> amazing
> > how difficult it is to wind this stuff. What a nightmare of kinking and
> > tangling the likes of which I've never seen before!
> > I finally get it built in a desparate hope that it will solve the lousy
> > stinking results I am getting and I put it on and it absolutely
stinks!!!
> The
> > sparks are not steady, the sparks are half the thickness I expected!
> >
> > Then there are the caps. Mine are not soaked in oil. Maybe I should do
> this but
> > I don't want to have to haul around two five gallon buckets of oil and a
> cap
> > inside. That's like having a hearing aid the size of an ice-cream truck!
> >
> > Well, after trying the tubing, I and looking in disgust at $35 worth of
> tubing
> > and other stuff that was a waste of money, I realize I could have bought
> their
> > 18" spark model NEW and all built from Information Unlimited for LESS!
> Sure it
> > would have cost $499 but I've spent more than that already!
> >
> > I don't have a machine shop! I hadn't been busted financially for years
> but
> > now, I can barely afford a soda! I do programming full time for a
company
> that
> > does financial reports and processes transactions.
> >
> > I didn't buy the one from information unlimited because I wanted the
> feeling of
> > accomplishment but after three months of spend spend, all I managed to
> buy
> > myself was weekend after weekend working in a sweaty back room, sick
from
> not
> > eating all day till 11PM because I got to get whatever failed
> modification
> > finished and then when it doesn't give the expected results and I can't
> figure
> > it out and I've tried everything I can think of I give up and revert
only
> to
> > find LESS results when I revert and wishing I hadn't tried the
> modification in
> > the first place.
> >
> > So, here I sit, I possibly have spent $700 bucks and what do I got but a
> truck
> > load of defeat!!
> >
> > Sorry for the rant, but I feel the need to warn those out there who are
> > considering trying this fine hobby out, you better be prepared to spend
> > thousands on tools and have a machine shop to make something that looks
> good
> > and operates well and loads of money and a whole lot of luck and once
you
> get
> > one that seem to work to your satisfaction DON'T mess with it. Build
> another
> > coil and keep the one you got. You might like me have to budget your
> buying for
> > half a year but at least you won't mess up what you have.
> >
> > I've been working on this it seem forever, and what do I got to show for
> it?
> > Some gain in knowledge and NO TESLA COIL AT ALL!! Every time I tried to
> modify
> > it, I was sorry,
> >
> > I wish I had bought one pre-made from somewhere. Sure I couldn't say "I
> built
> > it" but at least I'd have something to show instead of something that
> makes me
> > sick at heart just to look at it!!
> >
> > Thanks for letting me blow off steam. I hope I got the sense to give up
> and not
> > continue trying this but I have the feeling that I will just keep on
> trying to
> > the injury of my wallet and my self respect!
> >
> > 

WOW, nobody gives up with out a fight. when i was 14 yrs old an
electrician helped me make a tccoil and its output was close to 3 feet
without a toroid! boy i wished i had the exact plans NOW! we experienced
some type of flashover,the glass plate cap went boom and so did the water
heater element,and most of the telephones on the street! well it's 36 years
later and i'm coiling again but i know it will be a while before i see a
3footer!!! document-document-document. It makes it real easy to back up when
you hit a bad setup. otherwise you continue to fumble continuously and get
mad quick. I've been reading the mail and there are some of the best tc
tech's right here with all sorts of wisdom free and willing. I will try to
answer any scrounge questions you have from my email  ka1bbg1-at-mcttelecom-dot-com
brian......

> >
>
>
>
>