- Nobody making these anymore??????????????Message 1 of 6 , Jan 29, 2008View SourceNobody making these anymore??????????????
- I would hope there is a new generation on the horizon just thirsting for knowledge. I am still busy with the school static electricity show but admittedly zeroMessage 2 of 6 , Jan 29, 2008View Source
I would hope there is a new generation on the horizon just thirsting for knowledge. I am still busy with the school static electricity show but admittedly zero on construction,
Hope everyone had a good holiday.
From: VanDeGraaffGenerator@yahoogroups.com [mailto: VanDeGraaffGenerator@yahoogroups.com ] On Behalf Of saihager
Sent: Tuesday, January 29, 2008 5:32 PM
Subject: [VanDeGraaffGenerator] two months silence
Nobody making these anymore????? ?????????
- I had some time tonight to mess around with the digital camera to see how well it would pick up VDG sparks. A little off-the-wall but something to break theMessage 3 of 6 , Jan 29, 2008View SourceI had some time tonight to mess around with the digital camera to see
how well it would pick up VDG sparks. A little off-the-wall but
something to break the silence!
stormhighway.com | stormscenes.com | cisinternet.net
Phone: 304-346-7359 | Email: dan@...
"We have this treasure in earthen vessels, to show that
this power is from God, and not from us"
- 2 Corinthians 4:7
- I m back in school (hooray!) and very busy with that. Finally getting a degree after all these years... I have plans to build a VDG with the clear tube fromMessage 4 of 6 , Jan 30, 2008View SourceI'm back in school (hooray!) and very busy with that. Finally getting
a degree after all these years...
I have plans to build a VDG with the clear tube from one of those
silly bubbler tubes with plastic fish as the shaft, and a medium
hamsterball covered in aluminum tape for the ball.
And another using a very large hamsterball and larger PVC pipe, using
wheels from a large TV cart as the rollers.
I have a smallish VDG, commercially made, but the motor bearings are
worn out. Works very well before that.
I thought it would be cool to build two otherwise identical VDGs with
opposite polarity, and see if I can get some interesting things going
like long sparks and get small light objects to fly back and forth
--- In VanDeGraaffGenerator@yahoogroups.com, "saihager" <saihager@...>
> Nobody making these anymore??????????????
- ... Well mine is sprawled out on different parts of work bench and corner of floor 3/4 built, but; bought a new toy; Harley Sportster; and playing with thatMessage 5 of 6 , Jan 31, 2008View Source--- In VanDeGraaffGenerator@yahoogroups.com, "saihager" <saihager@...>
>Well mine is sprawled out on different parts of work bench and corner
> Nobody making these anymore??????????????
of floor 3/4 built, but; bought a new toy; Harley Sportster; and
playing with that for now.
- ... Well, it s mid-winter here in Chicago and many of my projects are on hold until Spring when the garage warms up. I d spent spent a considerable amount ofMessage 6 of 6 , Feb 3, 2008View Source--- In VanDeGraaffGenerator@yahoogroups.com, "saihager" <saihager@...>
>Well, it's mid-winter here in Chicago and many of my projects are on
> Nobody making these anymore??????????????
hold until Spring when the garage warms up. I'd spent spent a
considerable amount of time and effort on a VDG without finishing it
last Fall and finally bought a commercial one with ~17in top from
Science First. Both of my sons are in grade school and I'll probably
leave the completion of the home made VDG to one of them as a school
I ran into 2 situations which which side tracked me a bit while
finishing my VDG (4 inch PVC column, 19" garden gazing globe top, DC
universal motor with Variac speed control). First, I used a large
stainless steel garden globe, large for the money but almost
impossible to cut an access hole. Found someone who works on cars with
a plasma torch, that cut a nice though rough-edged hole into the globe
in just a couple of minutes. The rough edge of the hole access hole
needed to be covered with anti-corona putty and metal cannot be
pressure bent into an inward curve. It's simple enough to cover the
rough edge to prevent corona, just slit a piece of clear vinyl tuning
along the long side and fill it with anti-corona putty, then slide it
over the edge of the access hole. It works but the putty is very
expensive and there's no easy way to produce a smooth inward curve
along the access hole (ideally it would funnel into the globe). If you
don't have easy/free access to a plasma torch for cutting a hole into
a garden globe I'd recommend just buying a commercial VDG globe from
Science First, it might cost you 50% to 100% more than using garden
gazing sphere and cutting the access hole yourself but in the long run
you'll spend much less time and effort to get a usable globe.
The other problem I ran into was balancing the rollers at high speed.
I didn't expect that part to be difficult difficult since I have a
decent drill press, but in fact I chewed up a couple nice $35 pieces
of solid Nylon rod (roller) without getting the axle hole completely
centered correctly and the wobble in the heavy nylon rods at high
speed was too much. If I had a lathe I could have trued the roller, in
retrospect I should probably have used 3in PVC pipe for rollers and
glued in end plugs. That way I could have drilled center holes in a
bunch of end plugs for short PVC roller tubes and then tested the
rollers for balance, the rollers would only have cost a few cents each
so testing a bunch of them for balance wouldn't have cost much.
Since I started the VDG last year I did make a stack capacitor to go
with it using six 3.5 gallon buckets each lined with foil . It gives a
satisfying though not especially scary crack at discharge of about 1
inch after charging with my Science First VDG for a minute or so, the
total capacity of the stack was 3.4nF at about 60,000V (1.1 inch gap
between 1 inch spheres) giving almost exactly 6 Joules. That would be
a substantial shock to say the least but not usually considered to be
life threatening. Buckets are very expensive way to get capacitance
though. It's nice for a concept demo to show people since buckets look
big and impressive, but a HV capacitor as big as a flashlight battery
can hold many times the capacitance charge of a stack of buckets.
There are lots of big HV capacitors of all sorts on eBay for the
fearless. Stay away from them unless you are very knowledgeable in
electronics and a total safety freak, and can guarantee that others
won't get into them when you aren't around to supervise.
The VDG project did get me off on a HV tangent of interest though. We
got a nice 80KV induction coil, and we made a small sparker box out of
an old cigar box which uses a small 100KV battery operated HV coil
(another eBay find for about $20 used in taser type stun batons), push
a button on the front of the box and a fat 1 inch spark crackles
between 2 electrodes on the top of the box. It's a nice toy but it
produces a fair amount of ozone and is so loud that people come by to
see what the problem is. Also got a solid state Tesla coil, that's one
to be careful if used inside, you need separate grounding (wire to a
rod pounded into the earth) otherwise you may fry all electronics
hooked to your electrical outlets if the main sparks from tesla ever
manage to ground to your regular electrical system ground.
Surprisingly to me, our favorite HV device has turned out to be a 12
dia Megavolt plasma globe, it's a large out-of-production lightening
globe with beautify long blue lightening bolts which snake around
inside and which turn pink as they hit the glass of the globe. There
are many 8in dia plasma globes available maybe $35 if I recall which
are also impressive, I got lucky on finding a used 12" dia (A 12" tall
globe will only be 6" or 8" in globe diameter and sellers almost
always hide this fact in the small print). The plasma globe lets you
see large sinuous sparks close up without the ozone or danger - I use
that plasma globe a hundred times for each time I use the induction
coil. The plasma coil cost considerable more but the noise and ozone
make the induction coil an occasional thrill at best.
So as the weather warms up in a few moths we'll dust off our
unfinished projects and we'll bounce our way from one to another. Each
of these interests and discussion forums becomes a springboard to many
things new and unexpected. People come and go as their interests
evolve but the forum provides a nice place for us to leave our
impressions and small discoveries for those who may show up years later.
I'm hoping to get to 'Lightning on the Lawn' in Baraboo Wisconsin this
fall, it's hosted by Dr Resonance who produces commercial VDGS and
tesla coils. Check out this youtube link to see some short videos on
his huge Big Bertha tesla coil and singing tesla from the 2006 and
2007 Lightning on the Lawn gatherings;