Loading ...
Sorry, an error occurred while loading the content.

two months silence

Expand Messages
  • saihager
    Nobody making these anymore??????????????
    Message 1 of 6 , Jan 29, 2008
    • 0 Attachment
      Nobody making these anymore??????????????
    • Richard Linder
      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
      Message 2 of 6 , Jan 29, 2008
      • 0 Attachment

        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.

         

        Dick Linder

         


        From: VanDeGraaffGenerator@yahoogroups.com [mailto: VanDeGraaffGenerator@yahoogroups.com ] On Behalf Of saihager
        Sent: Tuesday, January 29, 2008 5:32 PM
        To: VanDeGraaffGenerator@yahoogroups.com
        Subject: [VanDeGraaffGenerator] two months silence

         

        Nobody making these anymore????? ?????????

      • Dan Robinson
        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 the
        Message 3 of 6 , Jan 29, 2008
        • 0 Attachment
          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 the silence!

          http://stormhighway.com/blog/jan3008a.shtml

          Dan

          --
          --------------------------------------------------------
          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
          --------------------------------------------------------
        • Steve
          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 from
          Message 4 of 6 , Jan 30, 2008
          • 0 Attachment
            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 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
            between them.

            Steve Greenfield

            --- In VanDeGraaffGenerator@yahoogroups.com, "saihager" <saihager@...>
            wrote:
            >
            > Nobody making these anymore??????????????
            >
          • saihager
            ... 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 that
            Message 5 of 6 , Jan 31, 2008
            • 0 Attachment
              --- In VanDeGraaffGenerator@yahoogroups.com, "saihager" <saihager@...>
              wrote:
              >
              > 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 that for now.
            • jpiperson2002
              ... 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 of
              Message 6 of 6 , Feb 3, 2008
              • 0 Attachment
                --- In VanDeGraaffGenerator@yahoogroups.com, "saihager" <saihager@...>
                wrote:
                >
                > Nobody making these anymore??????????????
                >

                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 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
                project.

                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;

                http://tinyurl.com/2jxs6k

                John Piper
              Your message has been successfully submitted and would be delivered to recipients shortly.