Bicycles/Thread locking compound

Thread locking compound is an adhesive designed to prevent parts from vibrating loose. Some brand names are Loc-Tite® and Permatex®. A light duty compound will be removable with simple hand tools. Heavier duty may require special equipment such as a heat gun. There are three standard Loctite grades

  • Blue Removable No.242 which is applied to fasteners that you may want to unscrew easily.
  • Red High-Strength No.271 which is applied to fasteners that you seldom need to remove.
  • Green is a wicking grade of Loc-Tite® used on joints which have already been assembled

Loctite was invented in 1953 by Vernon Krieble, PhD. It is described as an anaerobic sealant. In other words, it sets without air. To set it must be in the presence of metal ions and the absence of oxygen. this allows it to set properly inside an assembled fastening.