Pickup/guitar Shielding...

[Joe Gwinn]

Hey Guys,

I'm now in need of buying some shielding paint. Im good with either Aerosol or Brush on. People here talked about the compunds from MG chemicals and was wondering which would be better for guitar shielding purposes. Here are the specs of both

Product #841 - Super Shield - Nickel Flakes.

A general purpose EMI / RFI shielding spray for use on plastic electronics enclosures. Consists of a tough, durable acrylic base pigmented with a high purity nickel flake.

[snip]

Product #843 Silver Coated Copper Flakes

Reduces or eliminates EMI / RFI interference. A general purpose EMI / RFI shielding for use on plastic electronics enclosures. Consists of a tough, durable acrylic base pigmented with a high purity silver coated copper. Has a resistivity of 0.15 ohms • cm.

So the resistance of the Silver coated copper is lower. I just dont know which one is going to do a more effective job. Any suggestions?

The nickel works just fine. Ultra-low resistance is neither needed nor desirable.

[Joe Gwinn]

Last week i tryed to mesure the resistence of a 12 years old Alembic control cavity (silver color painting)and it was null, nothing .

Meaning open (infinity) or zero (short circuit)? How did you measure this?

[Achiles]

Minipa multimeter.It was like no conductive paiting.

[Joe Gwinn]

Minipa multimeter.It was like no conductive paiting.

So, it acted like an open circuit, with no current flowing?

What did you do with the multimeter to obtain the reading?

[Achiles]

Open citcuit;resistrnce reading,all escale.

[Joe Gwinn]

Open citcuit;resistrnce reading,all escale.

OK. It's an open circuit. I assume that you just stuck the two probe tips against the coating in a few places in the cavity. However, it can be hard to get good connection to a thin film with probes. Try laying two pieces of brass down on the floor of the cavity and pressing the probe tips against the pieces of brass. This will allow area contact to the film.

Does the film appear to have been from a water-based paint, or solvent-based? Is the film discolored?

[Achiles]

It has a pale aparence,very poor look.
The bass is not in my hand .

[David King]

I could certainly call Mica and ask her what they were using back then if it matters.

[Plucky]

The nickel is definitely magnetic, something to keep in mind when shielding plastic pickup covers.

David, are you saying that the nickel aerosol has a measurable ferrous content? I'm just wondering, as I have just bought some. Also, I was just told by one of the local MG Chemical retailers that they have discontinued the Super Shield product. I find that hard to believe, though...

[David Schwab]

David, are you saying that the nickel aerosol has a measurable ferrous content? I'm just wondering, as I have just bought some. Also, I was just told by one of the local MG Chemical retailers that they have discontinued the Super Shield product. I find that hard to believe, though...

Nickel is ferromagnetic. It doesn't have iron content though.

Don't forget that AlNiCo magnets contain nickel. Cobalt, and Chromium dioxide are also ferromagnetic.

Ferritic stainless steel has chromium in it.