Guitar Finishing. NitroCellouse lacquer is not so much a finish as it is a process. Lacquer is a finish that is derived from a secretion of the Laccifer Laca or Lac beetle. This sap is dried, washed, crushed and purified before being made into Shellac Flakes. The flakes are mixed with differnt spirits, depending on the final product. Shellac has an alcohol or spirit base. Lacquer has an acetone base.

To do a quality finish you need to follow these steps: seal, fill, seal, spray, and polish. The neck and body should be finished separately from each other. If you don't you will have a finish crack develop at the heel and if you ever need such a neck reset, the damage is very difficult to hide.

I recommend hand sanding the guitar. Seal the top with either a vinyl sealer or shellac. Give the top at least two even coats and one coat of lacquer before touching the rest of the guitar. As you stain and fill the sides and back, you might inadvertantly touch the top with some stain. The light finish prevents that stain from penetrating the wood, allowing a nice clean up.

With the top sealed and the sides sanded (120 grit) we are ready to go to work. Seal the sides and back at this point. The process is the same with both shellac and vinyl sealer, just follow the directions on the can. Thin the first coat about half and half. Allow proper drying time and then apply a full coat. This lets the sealer set well into the grain. After the sealer coat is dry lightly scuff with a scotch pad (maroon) of very fine grade. 0000 steel wool is ok but be sure to get all the steel fibers off the finish for the next step.

Stain and fill at the same time. Use a dark walnut stain for rosewood and a light walnut stain on mahogany. If you use mahogany stain you will have a reddish mess. I tried it once and didn't like it. Apply the stain you've picked to a small piece of scrap wood to see what it looks like. Use a filler that is mineral based. This allows more working time. If you use water based fillers you need to watch for grain raising. Jasco brand is a quality filler. Mix equal parts stain and filler before applying. The stain will thin the filler a little and let it flow into the grain openings better. Use a paint brush and give the sides and back a liberal coat. After the filler 'flashes' or loses it's wet appearance, rub the filler into the wood with a cotton rag. Look for balls of filler coming up. Remember you are trying to force the filler to fill the pores of the wood. Let the filler dry a few days, then scuff it out with 320 grit paper. Wipe clean and seal two more times; once with a thinned coat and once full strength. Let that dry for a few days and start again. Scuff out with the scotch pad or steel wool (0000) and you are ready to spray.

To spray lacquer is not that difficult. Try to keep your spraying area as dust free as possible. When you have a nice sealed coat on the guitar you can start with full 'out of the can' strength lacquer. Spray six coats with a forty-minute wait between coats. Let the body cure for at least three days, then scuff it out with 420 grit. Check for voids in the finish or defects that show. Fill these areas with lacquer using a modelers brush. Let set a few days and scuff flat. When you are happy with the coats and cover of finish, sand with 600 grit and then spray three more coats. Again, allow about forty minutes between coats. Let set for three days or more before prepping for the finish sanding.

For the finishing sanding you need paper of different grits: 800, 1000, 1500, 2000 and polishing paper. You also need maquires swirl remover - this is any good swirl removal product for cars. Start to sand using a block and water with a little soap in it, about one tablespoon soap per quart. Start with the lower grits (800) and work up to the polishing paper. This will give you a high gloss finish. Take your time. Allow at least six hours to go through all the steps. Go slow and you will get that wet look. To get the wet look you need the swirl remover and a power buffer. Any auto buffer will work. The wool bonnets work best. Keep the bonnet moving because you can burn the lacquer and, if you do, you will have to strip and start all over. Take you time and keep a close watch on the finish. You want a smooth almost water like finish. You can spray more lacquer if you don't have enough. If you follow these simple steps you should have a nice finish that you can be proud of.

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