After neglecting my Takamine acoustic guitar for a few years, the frets became tarnished and dull. Many guitarists would recommend rubbing steel wool against the frets to polish them up, but that's a fairly barbaric way to treat an axe. Not only will it booger up a nicely finished fretboard, but you'll get a million microscopic scratches from the filthy steel wool dust.
A better way is to use a Dremel rotary tool with some polishing compound, as recommended by this web site: http://www.projectguitar.com/tut/fret.htm. I already own a Dremel, so I bought the Dremel Polishing kit and some of the least "sticky" blue masking tape that I could find. The polishing process couldn't be simpler:
- Set the guitar on a table with a soft towel or blanket
- Remove the strings
- Cover the fretboard between the frets with blue tape
- Cover the guitar body with a towel (in case you slip or some other accident occurs)
- Attach a cylindrical felt polishing tip to your Dremel
- Rub the tip in the Dremel polishing compound
- Polish the frets with the Dremel at speeds no greater than around 4000 rpm.
- Use a clean paper towel or shop rag to rub the compound off the newly polished frets
The results are excellent, and the shiny frets on my guitar play totally smooth.
Note about tape: My guitar has an ebony fretboard, so the tape didn't leave any residue. However, the back of the neck is varnished, and some tape residue did remain. A simple Dan Erlewine trick removed it easily: a little saliva on a cloth rubbed the stickum right out.