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If the resistance per square is low enough for circuits, it's to low for shields. From all the reading of this forum, it seems that 500 to 2000 ohms per square is usable. To low and it reduces signal level, to high and the shielding effect is lost.
"Ohms per Square
The resistance of any square area of thin film resistive material as measured between two parallel sides.
A unit of resistivity for surface films and other materials whose thicknesses are considered to be negligible.
The resistivity of a very thin conductor is defined to be its resistance (in ohms) multiplied by its width and divided by its length. If the conductor is square in shape, then its length and width are the same and its resistivity is simply equal to the resistance of the square. Whatever the size of the square the number will be the same.
The distance unit is lost in the division, but convention uses Ohms per Square to describe the nature of the unit and measurement."
I bought a gallon of water based alkyd graphite paint. It has about 600 ohms/sq. Thinning it with water or another non conductive alkyd paint will result in higher resistance/sq. It will require some experimenting.
The original purpose of the paint is to provide a very slick non-stick surface when dry. Its used to coat the underside of lawn mowers, or most any kind of powdered or granular material handling equipment to promote free movement of the stuff. I will use part of it on my mower. It was $27/gal.
Rick -
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It would be good for screening plastic control boxes, I imagine.Comment
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A large area screw mount solder lug for contact and multiple layers of paint for lower resistance or just use aluminum foil.Comment
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