Nut Lubrication to Avoid String Breakage and Tuning Problems Here is a simple tip to help keep your guitar in tune, especially guitars with vibrato tailpieces. One of the most common places where tuning problems occur is at the nut. Strings can get “hung up” and not glide through their nut slots. Bending strings and use of a vibrato tailpiece can also cause them to go out of tune. The simple remedy for this is to lubricate the nut slots so that each string will glide freely and not get hung up wreaking havoc with your tuning. Products such as Big Bends Nut Sauce are designed specifically for this purpose. A little goes a long way and just a small droplet will keep the your strings gliding freely helping you keep your guitar in tune.