[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [TCML] A new guy with a primary threaded through holes
Hey John...
look at the last picture on this the page listed below.... notice how
the plastic does not totally encase the primary tube
http://members.cox.net/bunnikillr/primcoil.htm
Scot D
jhowson4@xxxxxxxxxxx wrote:
LOL, I have made that mistake before. =0
I don't fully understand this L's and C's business. Are there any closeup pictures or napkin diagrams that could help me out?
Thanks,
John "Jay" Howson IV
----- Original Message -----
From: "THOMAS RYCKMANS" <thomas.ryckmans@xxxxxxxxxx>
To: "Tesla Coil Mailing List" <tesla@xxxxxxxxxx>
Sent: Tuesday, May 18, 2010 1:02:26 AM GMT -05:00 US/Canada Eastern
Subject: Re: [TCML] A new guy with a primary threaded through holes
You have to redo all, it is wound the wrong way round!
No, seriously, it's not. Great job you did, I tried this way a long time
ago, found threading very difficult (after drilling of course...). So I just
removed a slice from my "L"s to transform the holes into "C" s. Forming the
copper was finished in the matter off miuntes after that
Thomas
On 18 May 2010 02:55, Joe Mastroianni <joe@xxxxxxxxxxxxxx> wrote:
My primary coil - http://gallery.me.com/iceowl
It is with no small degree of chagrin that I note Greg Leyh will not be
appearing at this week's Cal. Maker Faire. Were it not for his
demonstrations last year I would not be reading this list now, and typing
with raw fingers after threading 42' of 1/4" copper tubing through 96
stanchion holes. I am in process of creating my first coil thanks to Greg
and his small 20' purple arcs that spanned a big chunk of the show floor.
Alas, even the wife was so taken by Greg's display that she consented to my
coiling. Even encouraged me. Is even helping. Four hands winding the
copped through the holes worked better than two. This is how it starts, I
guess.
Ebay luck shone down upon me a few months ago and I scored 15/30 NPT. I
promptly built a jacob's ladder, and just as promptly grew bored with it.
Consequently I have been amassing parts to build my first coil. The
garage is beginning to fill with those white/red/blue Priority Mail boxes.
I can barely get the car in. After a trip to TAP plastics and an evening
throwing numbers into JAVATC I decided to start building. Now there is no
room for the car at all.
Previously, I had bought an 18 page paper written by a guy who went through
the mechanical structure of a static spark gap coil, and he advocated using
plastic cutting board material for the stanchions, and using 4. Four
seemed to offer less structural integrity than 6, and 6 (or 8) looked
better. I decided that it would be very difficult to thread the copper
around 8 stanchions placed 45 degrees apart because of friction and also,
the 1/2" polycarbonate would force the copper to follow a straight line
through its 1/2" length, which I felt might necessitate lots of bending. So
6. I decided on 6.
I built 6 stanchions to hold the primary by cutting "L" shaped pieces from
1/2" polycarbonate/Lexan I got from the Tap plastics cast off bin. With my
drill press I built a jig out of wood which allowed me to precisely drill 15
holes in the long leg of the "L". I drilled 5/16" holes and stepped them
inward by a couple 32nds on each subsequent stanchion to account for the
spiral winding. There is no engineering involved in my decision to drill
5/16" holes other than I knew I wanted a hole bigger than the O.D. of the
1/4" tubing and the only bit for drilling plastic they had at Tap plastics
that was bigger than 1/4" and smaller than 1/2" was 5/16". Turned out to
be fortuitous.
That evening I subscribed to pupman.com - which I had not previously
subscribed to because, well, no pictures. What a massive mistake. I
learned at about 2AM on Saturday morning that it would be impossible to
thread the copper through the 1/2" polycarbonate. Several had tried and
failed, as evident from their exasperated postings on this auspicious site.
But I had already made my investment in time and $$. So my choices were to
toss out what I had done and go the
LDPE-with-"C"-shaped-notches-instead-of-holes route, or beaver on mindlessly
as if I had never read the posts.
The next morning acrylic cement I glued the stanchions to a lexan circle I
also got at Tap. When you use that acrylic cement it bonds pretty
completely. It's as if the plastic becomes one piece. This was also
fortuitous.
At 2AM on Sunday morning I discovered some posts on pupman that described
some intrepid soul, some years ago, who actually accomplished what I was
about to try. Somewhat cryptically he said, "it's possible and I just did
it and it wasn't so hard". Though he did not describe his technique much
other than to mention the term "scootching".
I have learned what "scootching" is. But just to be safe, and to allow for
extra play, I beveled (countersunk?) each of the holes about 1/8" with a
fine stone bit on a dremel. I figured this would make it easier to thread
the copper as it came in to each hole at an angle.
When daylight broke I began threading the copper. Even though my stanchions
have more holes, I had decided to thread 13 clockwise turns. The 50'
section of copper I got came in a coil. I laid this coil over the
stanchions in the winding sense I desired and began threading the tubing
using the natural curve of the copper to follow the curve of the hole
pattern on my stanchions. The first 2 turns went swimmingly, and I wondered
what all the fuss was about. I put two hands on the tubing, forcing it
through the holes gently, turning it as if it was some sort of valve. I
could push the copper through the holes about 1/2" with each grunt. The
next 4 turns were a bit harder. And in fact, by the time the 4th turn was
through, I could only move the copper about 1/8" or maybe only a couple
millimeters with each effort of the hand. This took me about 90 minutes.
With a cup of coffee in hand I took a rest break, read more pupman, and
discovered someone suggested using Windex as a lubricant.
I will say it would have been completely impossible to thread the copper
through the holes without some form of lubricant. By the 5th turn the
friction was so great the coil could not be passed through the stanchions at
all. Slathering on windex - I suddenly had the ability to "scootch" the
coil clockwise about 1/16" with each twist. It didn't get much better than
this. In fact, it got worse. As I reached the inner turns of the coil, I
was squirting Windex into each hole pretty much with each turn of the coil.
By the time I got through the 10th turn, the coil was only rotating 1 or 2
millimeters with each "scootch". I had to manually twist each turn of the
coil individually, sometimes starting from the inside, sometimes from the
outside.
I believe I have put six hours into the coiling of the copper. It was not
easy. The results seem to be aesthetically pleasing, and of course, it's
very structurally rigid, especially since the windex has all evaporated now.
With regards,
Joe
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla