Painting A Guitar: Preserving The Sound

Painting a guitar can be a fun project, but many are concerned about how it might affect the sound of their instrument. When done correctly, painting a guitar should not affect its sound quality. However, it is important to prepare the guitar properly before painting, including stripping away any existing finish and sanding the surface to ensure a smooth and even coat of paint. The type of paint used is also important, as thicker paints can absorb vibrations and deaden the sound. Thinner coatings, such as lacquer or French shellac, are commonly used as they do not absorb vibrations as much. Additionally, not all parts of the guitar need to be painted, and it is important to disassemble the guitar and protect certain parts before beginning the painting process.

Use the right paint

Painting a guitar is a simple process but it requires the right tools and materials. The type of paint used is critical to ensuring that the sound quality of the guitar is not affected.

When it comes to choosing the right paint for your guitar, there are a few options to consider. Firstly, it is important to use a paint that is specifically designed for guitars. This could include nitro spray paints and varnishes. Using the correct type of paint will ensure that the paint adheres properly to the guitar's surface and does not flake or peel off.

For acoustic guitars, the choice of paint is particularly important as any coating will stifle the vibrations that make an acoustic guitar work. Lacquer or French shellac are commonly used as they are thin and relatively hard, minimising the absorption of vibrations. Nitrocellulose pigmented lacquer is another option that can be used instead of paint.

If you are looking for a specific finish, such as a mirror finish, specialist paints may be required. Enamel paint is recommended for a high-quality finish. It is important to avoid using paint that is too heavy, as this can affect the sound quality and result in a guitar that looks like a "chocolate-dipped pretzel".

Additionally, the type of wood used in the guitar can impact the choice of paint. For woods with a lot of grain, such as mahogany or ash, a grain filler is recommended to seal the pores of the wood before painting. This step can be skipped for woods with finer grains, such as alder or maple.

Prepare the guitar

To prepare your guitar for painting, the first step is to take it apart. Not every part of the guitar needs to be painted, and painting certain parts can damage them and affect the sound quality. Remove the guitar strings first by snipping and pulling them free from the bridge and pegs. You will need to restring the guitar with new strings once you've finished painting. If you have an electric guitar, use a screwdriver to remove the pickguard. You may need to first remove any knobs and the selector cap. Loosen the screws carefully and gently lift the pickguard away. If there are electronics attached, unscrew any pickups and pots before removing the pickguard. Depending on your guitar, you may also need to unscrew and remove the neck.

Before you begin painting, you should fill in any holes or gaps in the wood grain. While these are natural, they can affect the finish of your paint job. Use an all-purpose wood filler, which is compatible with various coatings. Apply the grain filler with a putty knife or a credit card until the surface is level. Leave the filler to dry completely, and then use fine sandpaper to rough up the surface. Sanding will provide the right texture for the next steps and remove any excess filler.

Next, use a mineral oil paint thinner to remove dust and oils from the bare wood. Apply a thin layer of the oil to one side of the guitar and leave it to dry. This step will ensure that the paint adheres properly to the surface.

If your guitar has an old paint job, you will need to remove the old paint entirely before proceeding with a new coat of paint. Use coarse sandpaper to sand down the old paint, and then switch to fine or ultra-fine sandpaper to smooth out the surface. Work with the wood grain, gently sanding the guitar's body. You can use a wet sanding technique for a cleaner finish. Dip the sandpaper in water between passes and sand with a sweeping motion.

It is important to work in a clean and dry space, with temperatures between 15 and 30 degrees Celsius. High humidity or extreme temperatures can negatively impact the final result. Make sure to sweep, vacuum, and dispose of any dust in your workspace.

Seal the wood

Sealing the wood of your guitar is an important step in the painting process. Firstly, it's crucial to understand that holes and gaps naturally occur in the wood grain. While these are natural, they can impact the finish of your paint job and the sound of your guitar. To address this issue, use a wood sealer or an all-purpose wood filler, which is compatible with various coatings. Apply the grain filler evenly using a putty knife or a credit card until you achieve a smooth surface. Allow sufficient time for the filler to dry completely.

Once the filler has dried, use fine sandpaper to gently sand the guitar's surface. This step helps create the right texture for the subsequent steps and ensures the removal of any excess filler outside the crevices. After sanding, use a mineral oil paint thinner to remove dust and oils from the bare wood. Apply a thin layer of the thinner using a microfiber cloth on one side of the guitar and let it dry.

Additionally, consider sealing the inside of your guitar, which can provide several benefits. Firstly, it helps regulate humidity by slowing down and evening out the rate of moisture absorption. This protection against moisture absorption can also safeguard your guitar against potential shock and damage over time. Secondly, sealing the inside of the guitar can positively impact its sound. Think of it as treating the space inside the guitar like treating a room acoustically.

When it comes to the type of sealer to use, shellac is a common option. However, be mindful that the application of sealer may vary depending on the specific type of guitar you have. For example, arch-top guitars are particularly sensitive to humidity changes, and sealing can help mitigate this issue.

Remember, appropriately done, painting a guitar should not significantly affect sound quality. Professional-quality electric guitars are often painted and known for their excellent sound. However, if you're concerned about the finish or have a valuable guitar, consider seeking professional help for refinishing. Additionally, if you're repainting an acoustic guitar's sound hole rosette, remember to sand the sound hole area thoroughly and clean your workspace to ensure a clean finish. Also, be mindful that any coating will slightly affect the vibrations of an acoustic guitar, so opt for thinner coatings like lacquer or French shellac. If you're unsure about the paint type, inexpensive guitars are a good option to experiment with, as you're less likely to notice a significant sound difference.

Apply the paint

Now that your guitar is ready, it's time to paint! If you're using a wood filler, apply it with a putty knife or a credit card until the surface is level. Let it dry and then sand the guitar with fine sandpaper. Next, use a microfiber cloth to apply a thin layer of mineral oil paint thinner to remove any dust and oils.

When you're ready to paint, make sure you're in a clean, dry place with temperatures between 15 and 30 degrees Celsius. Humidity and temperature can affect the final result. Use a sanding sponge or wrap the sandpaper around a sponge, and gently sand the guitar's body, working with the wood grain. You can use a wet sanding technique for a clean finish—just be sure to dip the paper in water between passes.

If you're using a varnish or nitro spray paint, follow the manufacturer's instructions for application distance and drying time. Apply the paint in thin coats, and sand between coats with fine sandpaper until you achieve a uniform finish. Depending on the type of wood, you may need to apply additional coats of paint or primer.

For acoustic guitars, if you're repainting the sound hole rosette, be sure to sand the sound hole area as well. Use fine or ultra-fine sandpaper and focus on achieving a smooth, even finish. You can use a sanding sponge to help achieve this. Remember, the final aspect of your guitar will depend on the smoothness of the finish.

If you're using a lacquer, such as Nitorlack Lacquer, apply at least 3-4 coats, sanding between coats with P800 sandpaper until you achieve a uniform finish. This will help protect the colour and give depth to the final look.

Finish and reassemble

Once you have finished painting your guitar, you will need to seal the paint with a lacquer. This will protect the colour and give depth to the finish. Sand with P800 sandpaper between coats until you achieve a uniform finish. Apply at least 3 to 4 coats of lacquer. You can use Nitorlack Lacquer Golden Age, or a nitrocellulose pigmented lacquer.

After painting, you will need to reassemble your guitar. This is essentially the reverse of the disassembly process. Reattach the neck of the guitar, restring it with fresh strings, and reattach the pickguard and any electronics. Finally, tune your guitar and you're ready to play!

It is important to note that the reassembly process may vary depending on the type of guitar you have and the extent of the disassembly. If you are unsure about any part of the process, it is best to consult a professional or seek further guidance.

Additionally, the environment in which you conduct the finishing process is crucial. Ensure that you work in a clean, dry place, with temperatures between 15 and 30 degrees Celsius. High humidity or extreme temperatures can negatively impact the final result.

Frequently asked questions