Glues and Gluing
Woodworking adhesives, used correctly, are stronger than wood
Synopsis: Certain basic considerations that may be overlooked or misunderstood are too often the causes of serious gluing problems and are worthy of systematic review. In this article, R. Bruce Hoadley addresses why glue sticks at all, discussing the fundamentals of how it works before talking about wood itself — how its cell structure affects success, endgrain vs. grain surfaces, and permeability. Moisture content affects how well glue works, as does time and how it’s spread. He discusses clamps and various types of glues, such as hide glue, casein glue, polyvinyl resin emulsions, resorcinol formaldehyde, urea-formaldehyde glues, melamine adhesive, holt melts, epoxy, and contact cements.
The general term “adhesive” covers any substance that can hold two materials together by surface attachment. Those most commonly used for wood are called “glues,” although materials described as “resins,” “cements” and “mastics” are equally important in the assembly of wood products. Today’s woodworkers use…