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previous: Et_La I have a question about shieldind a... -- 1100180017 View Thread

Re: Graphite paint on bottom flendge

11/11/2004 8:32 PM
Joe Gwinn
Re: Graphite paint on bottom flendge
On 11/11/2004 1:33 PM, Et_La said:  
"I was just wondering if it's a good idea painting the bottom flange of a P90 with graphite paint and put a third eyelet for the ground wire. I thing this way the eddy current effects will be very low and shielding will still be acceptable."
Graphite paint has a high enough sheet resistance that eddy currents will not be significant.  
Sheet resistance is specified in ohms per square, because if one makes a square of some sheet, with low resistance connections on two opposite (and parallel) sides, the resistance does not depend on the size of the square.  
Nickel powder paint has a sheet resistance of about an ohm per square. Silver powder paint is about a tenth of an ohm per square, and graphite paint is tens to hundreds of ohms per square. Metals are hundredeths to thousandths of an ohm per square, for foils and thin sheets.

Et_La Dwight i was talking about the pick... -- 11/12/2004 11:43 AM