We’re surrounded by electrical interference. Guitar pickups act as little antenna that can pick up this interference. Guitars with single coil pickups are especially prone to this, making them noisier than we’d like.

‘Shielding’ is one way of mitigating this problem. The objective is to create a protective ‘box’ around your guitar’s wiring and electrics to keep out potential interference.

The job requires patience and attention to detail but can be well worth the effort.

Your shielding options

There are basically two options for shielding your guitar’s electronics: conductive paint and conductive copper tape. There are pros and cons to each.

Using shielded guitar wire can also make a difference, though it costs more.

To effectively shield your guitar with copper tape, follow these guidelines:

1. Clean the cavity of any loose wood chips or dust. This helps creates a clean flat surface for the tape to adhere to.

2. Make sure that adjacent pieces of tape overlap by about 5mm.

3. When shielding cavities, bring the tape up in a slight ‘lip’ over the edges of the cavity (2-3mm is enough) so it makes contact with the cavity cover and scratchplate when they’re screwed down.

4. Shield the underside of the cavity covers or scratchplate, making sure they will make contact with the ‘lip’ all the way around the cavities. Your scratchplate only needs to be shielded in the areas covering the cavities (this also saves you money on tape).

5. Shield all cavities containing an electrical component: pickup cavities, control cavities and switch cavities.

6. All shielded areas need to be connected. This means that different pickup cavities, or the cavities on the front and rear of a guitar, need to be connected with a wire. Standard guitar electrical wire is fine – attach it at either end by soldering it to the tape, or by sticking the exposed wire ends down with more copper tape.

Grounding

The shielded areas must be grounded. This means they must connect to a ground point in the guitar’s electrical circuit.

If the pots (potentiometers) on your guitar come into contact with the shielding (which they should do either in the cavity or on the underside of the scratchplate) then job done – the pots are already grounded so the shielded areas will be too.

In the unlikely event that the shielding does not connect to ground, add a wire from the shielding to the common ground point (usually the back of a pot).

Finally, check that no ‘hot’ wires, terminals or solder points are coming into (or could come into) contact with the shielding. If this happens, the guitar’s signal will be sent to ground and you will hear no sound. This can easily happen if you have shielded the jack output cavity: when you plug in your guitar cable parts of the jack inside the guitar can be pressed against the cavity walls and into contact with the shielding.

You can avoid this problem by covering ‘hot’ terminals and exposed wire with rubber tubing or some tape (but not copper tape!).

Final checks…

Ensure there are no gaps between pieces of tape through which a rogue signal could enter. Check hard-to-reach places and all corners and edges.

Use a multimeter on the ‘continuity’ setting to check for electrical continuity between all areas of the shielded cavity, and between cavities. Any issues can usually be resolved by making sure tape is overlapping, continuous and stuck down, or by adding more tape.

Once you’ve reconnected and re-installed the guitar’s electrics, make sure once again that no ‘hot’ terminals are coming into contact with the shielding. This can happen if the body of a pot sits flat on the cavity surface or on the underside of the pickguard. Bare wiring or solder points can also touch things they’re not supposed to if space is tight or if the wiring is less than neat.