Guitar shielding paint is known as electrically conductive paint, emf shielding paint or EMI shielding paint. The paint comprises traditional polymer binders with electrically conductive fillers like carbon, nickel and silver. When applied over non-conductive surfaces like plastic and wood, the paint acts as a barrier to block unwanted electromagnetic waves. These waves interfere with electronics and can cause misfire and malfunction. In the context of electric guitars, we are simply applying the paints to solving the issue of an unwanted, persistent hum.
What Causes the Annoying Hum in Electric Guitars?
Electric guitar enthusiasts have no doubt had to deal with annoying buzzing and humming, making the guitar sound muffled and flat. These unwanted noises are magnetic fields generated by neighboring electronics, such as cables, transmitters, Wi-Fi, and even indoor lighting. The waves can travel and cause the guitar’s pickup to resonate. More specifically, these magnetic fields resonate with the wire coils wrapped around the pickup, producing an electric current. The pickup amplifies the signal and converts it into sound. The diagram shown below illustrates how the guitar pickup resonates with external magnetic fields.
What is the Solution?
You can easily eliminate unwanted interference by lining the cavity under the pickup with an electrically conductive material. Most guitar manufacturers and enthusiasts use copper foil which while effective, is cumbersome to apply and the material is prone to tearing, which creates gaps where signals can penetrate. Further, solid materials like foil do not conform well to complex geometries; therefore, sections can remain unshielded and prone to pickup unwanted signals.
An easier and more effective way to reduce noise and achieve a smooth, clean sound is to use a guitar shielding paint. Products like our 841WB Water-based Nickel Conductive Paint, effectively block unwanted signals, achieves excellent coverage and is highly durable. This paint is a one-part nickel conductive coating that bonds strongly to wood, has little odor and effectively shields over 99% of unwanted signals. The paint is dry within about 30 minutes of application and achieves full cure within 24 hours.
The paint is like a Faraday cage around the wire coils, blocking external fields so that the pickup only resonates to the magnetic fields from the strummed guitar strings. Our electric guitar paint is water-based, eliminating the hazard of paint fumes, adheres well to wood, and makes clean up quick and simple.
How to Apply Guitar Shielding Paint for Cleaner Sound
Start by removing the neck of the guitar. Clamp down on the strings with a capo and remove the screws at the back. You can now expose the cavity under the pickup without having to remove the strings. Remove the pickguard to give you direct access to the pickup cavity which is where you’ll apply the paint.
Clean the surface of the pickup cavity to remove any oils or fingerprint residue using Isopropyl alcohol like our 824. Use a simple horse hair brush to apply the paint inside the guitar cavity. Please note that you do not need to thin out the paint and can apply onto the cavity as sold. Allow 30 minutes for the paint to dry before applying a second coat. A second coat helps ensure there are no gaps in the shielding.
To check the quality of the coating, take a multimeter and set it to read resistance. Use the lowest range and place the probes on two points within the coating. The meter should register readings close to zero. Once you’ve confirmed the conductivity of the cavity, you can reattach the neck and enjoy the smooth, clean sound.
