Building: Chapter 5. This tutorial on building an acoustic guitar is broken up into six chapters. Jump to chapter: 1 - 2 - 3 - 4 - 5 - 6

Chapter 5 - Filling And Sealing
You are now ready to fill and seal the body. This is also how the neck and head stock will be done. I like to use Pasco brand wood filler and Minwax Dark Walnut stain. I mix about 5 tablespoons worth of filler and about 3 tablespoons of stain. Stir well to get the lumps out. I will let this set for about 10 minutes to set up a bit. It makes it flash better.

I have used a few different methods to fill. It depends on the amount of pitting on the wood surface. You may have to fill 2 or 3 times to get a good fill but it will make you finish so much better. This is the beginning for that perfect finish you are looking for, so take your time. No short cuts.

Applying The Filler
With a 2 inch plastic putty knife, apply the filler across the grain. Don't get too heavy, you want to fill the grain. You can also use a paint brush and brush it on and let it set until the shine goes away. When that happens - that is called flash - you can rub against the grain with a clean rag. You want to work the filler as deep into the wood as you can. Let it set overnight then light buff off with a scotch pad or 0000 steel wool. I prefer the scotch pad as the steel wool makes so much more dirt. Hold the wood up near a light and see how reflective you are. You should be able to see the dips where the filler had to go deep. If you have a lot of dips repeat the process. If you have voids at the binding areas you can mix some filler at this point and fill the holes and imperfections.

Scuff Sanding
Once you have a good base you can trim the binding and scuff sand. I use a very fine non loading sandpaper. 320 grit or finer. Again look at the wood by holding it against a light source. If the face looks pretty good you can do the sealer coat. I use a vinyl sanding sealer. There are many types out there and you must chose the one you want. I like to give the wood 2 nice even coats. Lighter being the better. Let this set up and again scuff sand.

Clean the wood with naphtha (lighter fluid) to remove as much of the dust as you can. This is the beginning of the finishing so be sure that you have good base coverage. You want to finish out with about .008 after wet sanding and buffing.

The Finishing Process
The finishing process is determined by what you are finishing with. If you don't have spray equipment and are planning on using spray cans you need about 5-6 cans of finish.

I will spray 6 coats with about 45 minutes between coats on lacquer. Please be sure that you are in a well ventilated area and are wearing the correct equipment. Let the spray set up for at least 3 days, wet sand with 400 600 and see that the finish is smoothing up. Then wipe off and give it 2-3 more coats. Wet sand after 3 days with 600-800-1000-1200. The finish should start looking good by now. You can polish it with the compounds and check that you have good coverage. Should you need more, wipe down with the naphtha and give it 2 coats and repeat.

• continue to chapter 6 >>