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Pore Filling Using Drywall Compound – Full Text

If you want a smooth finish on your guitar, then you must pore fill porous wood before applying that finish. Pore filling is one of the topics that I talk about and demonstrate in my guitar finishing DVD. Although there are many commercial products available for pore filling, I have chosen to choose drywall compound to demonstrate pore filling in this video. This is a product that is inexpensive and easily found around the world. It even says right on the side of the container that is sands easily. What else could you ask for? Before doing any pore filling, a few steps need to be taken to guarantee a quality job. The first thing I do is seal the soundboard. Here, I am using shellac to do that. Only a light coat is necessary. This will help keep the soundboard clean throughout the pore filling process. Next, I apply a solution of 50% lacquer and 50% thinner to all of my white purfling lines. This helps keep them from getting dirty while pore filling. A small piece of cotton on a stick works well for this. It will easily sand off when removing the pore filler. After thoroughly mixing the drywall compound, I place a small amount into a container like a plastic cup. Next, I dye the color compound to match the color of my wood. Actually, I like to make my pore filler darker than the wood itself. Therefore, I use black. Using a darker pore filler can actually add depth to the wood. It works well on woods even like Mahogany. Since drywall compound is a water based product, make sure that you use a dye that is compatible with a water based product. Next, add a small amount of the pore filler to a small area of the back of the guitar. Now use a rag or a paper towel to work the pore filler into the grain. Notice how I’m using circles and going across the grain. Unless you really like sanding, it’s good to wipe off the excess quickly and keep the surface as clean as possible. This product, as well as most water based products, dries very quickly, so you’ve got to work fast. After completing one small are, apply some more pore filler to another small area and repeat the process.