Best ElectroStatic Influence Machine?

What's the best electro-static influence machine?  Like which one can output the best sparks for the spinning input, ie which one is the most efficient?

Sectorless Wimshurst (Bonnetti)
Van De Graff

Or some friction (not influence) based electrostatic machine?

All of the influence machines are pretty similar, but I need to make a fairly small one (think disk diameters of only 3 or 4 inches), and i'm trying to make it hand held, so efficiency is a must!

sort by: active | newest | oldest
VDG isnt charged by friction - there is no "rubbing" involved.
guyfrom7up (author)  Tool Using Animal8 years ago
from what i see (and there isn't a whole lot of resources for Dirods), isn't it pretty much just a wimshurst machine using rods instead of sectors?
It has the advantage of using a single rotating disk, simpler construction than a pair of contra-rotating disks.
just in case you don't know about it, here is a neat page
Kiteman8 years ago
VdG isn't an influence machine, it charges by friction.

Otherwise, Whimhurst would be my preference.
guyfrom7up (author)  Kiteman8 years ago
right now I'm sort of leaning towards the wimshurst