Target's large bowls have changed a bit
- Whenever I am at Target I always take a quick look to see if they
still carry the 14" bowls with the straight sides (look in photos
under Craig's, I have a couple set up "VDG style"). I noticed that
they have added a little lip to the edge, which makes things a bit
harder for people like us.
I suppose it might look better on a sofa table with the lip, but not
so great on a VDG. I'm glad I bought 4 of them when I did, even
though I was really questioning the purchase at the time (I'm sure you
know what I mean, "Did I really need to buy so many?")
I like Lyonel's idea of making a clamp to press the hemisphere down
onto a rounded shape. The leakage from the column entrance is such a
charge killer. I was wondering how much this widens the opening after
it has been curved inward. Has anyone else tried it?
Another thing, has anyone checked to see if Ikea still has the 14"
- Franklin B. Lee said ' The opening which admits the belt to the
collector ought not to be much larger than half the diameter of the
collector and should be smoothly curved inward, using a generous radius
of curvature. Unpolished commercial aluminium spinning, free of lint
and dust, will collect about 85 per cent of the theorical maximum.A
high polish will increase the voltage another 1 per cent. The
concentration of charge around the hole through which the belt enters
accounts for the remaining 14 per cent, a quantity which varies with
the size of the hole and its distance from other conductors.'
J.G. Trump gave an excellent example of the correct design of a Van
de Graaff high voltage terminal. Instead of a sphere, the terminal is a
flat topped toroid. Equipotential rings are used on the supporting
column ( 500 kV @ 200 microamp. is generated by this 1938 design ). (
Dr Lyonel Baum
Le 10 oct. 06, à 16:03, Craig Fuller a écrit :
> I like Lyonel's idea of making a clamp to press the hemisphere down
> onto a rounded shape. The leakage from the column entrance is such a
> charge killer. I was wondering how much this widens the opening after
> it has been curved inward. Has anyone else tried it?