The tuning pegs may occasionally be treated with "peg dope" when they either slip too freely, causing the string to go flat or slack, or when they stick, making tuning difficult. Some violinists and luthiers use a small amount of ordinary blackboard chalk on pegs to cure slippage. "Peg drops" (a solution of rosin in alcohol) may occasionally be used to treat slipping pegs, but that is a temporary solution at best; quite often slipping pegs have shafts which are no longer smoothly conical and should be refitted or replaced.