Construction and Operation of a small Van De Graaff machine (Part two of two)

Part Two. Showing completed assembly and some sparks. Function of field shapers/corona rings is demonstrated.
This machine seems to be reaching over 300 kiloVolts today.

Category:

Science & Technology

Tags:

• Van
• De
• Graaff
• electrostatic
• high
• voltage

[jupy921]

Cool stuff man, I really like your design. You're getting a good output from this thing. The Hubcap looks an alwful lot like a UFO. :)

[TinselKoala]

Thanks, I think so too. I keep expecting to see it as a "sighting" on one of the UFOlogy sites. It sort of looks like it's beaming something up, with the blue light.

[talktoyourself]

Okay, how do these field shaping coils work? Does the metal used affect the warping of the electrostatic field? Could Aluminum foil be used? Thanks for all your great vids Mr. Nikola Tesla.

[TinselKoala]

I think they work by effectively reducing the curvature of the capacity shape. In these machines there is a really sharp edge where I cut the hole into the SS bowl for the tube to enter. The E field at this edge is so great that charge blows off and doesn't allow the voltage to build up. The field shapers, I think, work by reducing this curvature as felt by the field, thus keeping more charge on the bowl so the voltage can build.

AL foil would probably work, as long as you keep it smooth.

[TinselKoala]

And of course big commercial machines use a "re-entrant" shape, that pulls this edge up into the interior of the shape, so that there isn't a sharp edge outside to lose charge. In some of my machines using SS bowls or hubcaps I have been able to simulate the "re-entrance" by using various combinations of different sized bowls, some inverted and some upright.

It can make a huge difference in performance of the machine. Look at your machine in the dark to find corona leaks, and smooth them out.

[Magluvin]

Have You tried earth ground for the base? The one we had in school, the base did not emit a charge. Ya might get a few more electrons to flow to the top. As my teacher explained, the earth ground provided more free electrons to build a bigger charge. Same as a crystal set AM radio. If the ground of the crystal set is just a pipe that is not connected to anything(earth ground), the signal in the crystal set will be there, but very weak.

Be interesting to see. =]

[TinselKoala]

Yes, I guess I forgot to mention, the base is grounded to a copper cold water pipe under the kitchen sink. I installed the banana jacks in the base for grounding, interconnections, and mounting the voltage regulator (an adjustable spike that "pokes" the field and prevents it from building past a certain tension) or experiments or demos like the Coke can.

BTW, I posted a new video, "Chaos Motor", for the easily-entertained. Please watch, it is exceptionally boring yet fascinating simultaneously.

[2012thedevil]

hey bro, you should add a  water capacitor for longer and thicker louder sparks. It only cost like 10 bucks and I have yet to see someone use one.

[CRITZKRIEG]

You should bounce over to ikea

They have perfect half circle bowls

[GreatestWeirdos]

Wow this really makes it seem easy to make a van de graff! I really just love these things. It was helpful in me making one. Thanks.