I am please to pass along a message I wrote to Joshua, electrical wizard extraordnaire, and his reply:
(to know more visit: http://www.glubco.com/weaponry)

At 11:28 AM 12/12/98 -0500, Joshua wrote:
>We in the field of Historic Preservation must know more about the paint
removal effects of your Tesla Coil efforts. We have always known that Tesla
had a lot to offer the world and are not supprised that even after death he
can help us save our historic buildings.
>
>Could you take some close up photos of the areas in which paint was
removed and post them on your website?
>
>Please feel free to be in private communication on this matter. Who knows
who is listening...
>
>Inquiring minds want to know more....
>
>John Leeke, Preservation Consultant
>www.HistoricHomeWorks.com
> 

I don't have any close ups , sorry.
Basically, if the material which the paint is applied to is grounded (I.E.
concrete or cement, stone, ect.) the strong high frequency electrical
fields which are produced by the tesla coil will polarize the paint next on
the grounded surface (or really any surface). This polarization reverses at
a high frequency causing mechanical stresses between the surface and the
paint. Eventually the weakend bond breaks under the intense electrical
fields and the paint "pops" off. Also thermal expansion of moisture in the
base material can cause the paint to peel off from the coil as the RF
energy produced causes moisture to vaporize.

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     ||           Joshua Resnick            ||
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  _||||||_http://www.glubco.com/weaponry _||||||_
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