What to look for when fixing stringed instruments

Whether it's a guitar, violin or another stringed instrument (or the amp you use with them), even with the finest care, something is bound to go off eventually. Here's what to check for and how to aid some common things that will need adjusting.

• Chances are, the neck of your electric or acoustic guitar will need an adjustment at some point.
• This is most evident if you notice the intonation is off or if it takes more pressure than usual to push down the strings.
• You can easily tell if the neck of your guitar is warped by removing the strings and laying a yardstick on its edge across the length of the neck.
• It should lie evenly across the frets. If not, the neck needs an adjustment. You can get it adjusted at most stores that sell guitars.

• If the knobs of your electric guitar start producing unwanted noise when you turn them, it's probably due to accumulations of dust and dirt in the potentiometers.
• Clean them out twice a year by removing the knobs and spraying a bit of oil lubricant directly into each pot.
• Then replace the knob, and thoroughly work in the lubricant by turning the knob back and forth several times. Unplug the guitar and amplifier before cleaning.

• The pegs of any stringed instrument should turn freely without slipping or rubbing against the sides of the pegbox.
• When pegs start to slip, they need to be refitted. A dry environment can cause pegs to shrink and slip, while excessive humidity can make them swell up and stick.
• Never force a peg into the pegbox if it slips or gets stuck; you could break it or damage the pegbox.
• If a string becomes pinched against the side of the pegbox, have it professionally repaired as soon as possible; continued friction on it can break the string or crack the pegbox.

• Do you have an old instrument amplifier that's missing a knob or two?
• If you can't find replacements or keep forgetting to look, you can at least stop guessing about your amp's settings by making your own replacement knobs.
• Start by cutting off a 19-millimetre (3/4-inch) piece from a wine cork. (You need a real cork, not one of those plastic stoppers they put in some wine bottles these days.)
• Then carefully insert a sharp knife twice into one end of the cork so that it forms an X.
• Now, with a permanent marker, draw a straight line on the other side of the cork from the centre to the edge.
• Turn the potentiometer all the way down to its lowest setting, and gently work the cut-side of the cork (with the line in the appropriate position) over the pot.
• Viola! You're back in business.