How about Gold Leaf for Shielding?

[Russ_NY]

I really hadn't considered silver wire but I was seriously considering trying gold leaf as a shielding material for a coil. It is ultra thin and I think it might actually work. Would probably be a real pain to apply though. Any thoughts???

Russ

[Eric Foster]

Re: How about Gold Leaf for Shielding?

Someone once suggested that I ought to use gold wire for search coil windings to enhance the sensitivity to gold objects. The only difference one would notice compared with copper wire, is the cost and weight.

Same goes for shielding. Doesn’t really matter what conductive material is used as long as its conductivity is sufficient to minimise capacitive effects of the ground and attenuate electromagnetic interference, while passing the wanted transmit and received signals without hindrance. Higher conductivity shielding materials, e.g. copper, aluminium, would need to be thinner than lower conductivity materials, such as lead, stainless steel mesh, graphite or nickel sprays etc., for the same shielding performance. Gold leaf would be far too thin to be an effective shield. One Internet site gave its thickness at 1/250,000in. You would need, depending on the carat, gold foil about one or two thousandths in. thick. Still interested

Eric.

[Brian]

Re: How about Gold Leaf for Shielding?

Re your coil windings comment why isn't aluminium wire used in coils ?
No trouble with your P.I. coils as they are but many manufactures don't seem to really have taken on board the the discomfort caused by some of the larger coils creating an unbalanced, nose heavy detector.

[Eric Foster]

Coil Weight.

Hi Brian,

Aluminium wire has been used in PI coils in the past, but that was in the days when thicker wire was used and more amps pumped round the winding. I doubt if my present coils would benefit much from the weight saving. The Goldquest uses 0.25mm solid wire and the Deepstar and Aquastar 10/0.1mm stranded. I can save more weight by attention to the coil shell design and the types of potting resin used, with the result that the 11in coil for the Goldquest only weighs 14oz., excluding the cable and plug. This is with lead shielding too!

I agree that saving weight in the coil is of great importance. Detecting is no fun is your arm is in constant pain.

The other difficulties with aluminium wire are the problems of soldering. Can be done, but not so easy as tinned copper wire.

Eric.