Is Wood Glue Flammable? Understanding the Safety of Glue in Woodworking

Woodworking is an art and a craft that has been around for centuries. From simple farm implements to intricate furniture pieces, wood glue has played a crucial role in ensuring pieces are put together securely and last for generations. However, as with any material, there are important safety considerations, particularly regarding the flammability of different types of wood glue. In this article, we will explore the flammability of wood glues and provide guidance to ensure your woodworking projects are as safe as possible.

Historical Perspective: Early Glue_usage

Back in the 1960s, when I was a trainee joiner, the first task I was given involved boiling fish glue, a traditional form of animal glue. Despite giving off an unpleasant smell, it was highly effective and could set rock hard in just 60 minutes when applied. This was a different time when PVA (Polyvinyl Acetate) wood glue was yet to be introduced. PVA wood glue, in contrast, is odorless and sets in around 30 minutes, and is not flammable. This significant difference in properties highlights the evolution of woodworking materials and our understanding of safety standards.

Types of Wood Glue and Their Flammability

Not all wood glues are created equal, especially in terms of their flammability. Let's break down the flammability risks associated with some common types of wood glue used in woodworking.

Polyvinyl Acetate (PVA) Glue

Known as carpenter's glue, PVA glue is available in both liquid and solid forms. It is odorless, with a fast-setting time, and is considered non-flammable. This makes it a popular choice for woodworkers. The absence of flammable solvents reduces the risk of ignition, making PVA glue a safer option in many situations.

Urethane-Based Glue: Gorilla Glue

Gorilla Glue is a well-known urethane-based adhesive that is known for its strength and ability to bond most materials. However, the solvents in urethane glues can be flammable, both in liquid and dried forms. While the dried glue itself is not typically considered flammable, the liquid form can ignite if exposed to sufficient heat or flames. This underscores the importance of proper handling and storage when working with such glues.

Cyanoacrylate (Krazy Glue) and Its Flammability

Cyanoacrylate, commonly known as Krazy Glue, uses a hydrocarbon solvent that can ignite in liquid form. While the dried glue may not be flammable, the liquid can pose a fire risk if not handled carefully. This highlights the need for caution when using cyanoacrylate glue, especially in environments where it might come into contact with heat sources.

Epoxy Glue: Non-Flammable Properties

Epoxy glues are known for their excellent strength and durability, making them a favorite among serious woodworkers. Unlike many other types of glues, epoxies are generally non-flammable. However, some epoxies contain components like di-isocyanate, which may not significantly increase flammability. Nevertheless, it is essential to follow all safety guidelines, as epoxies are still flammable in certain conditions.

Practical Safety Measures

While different types of wood glues have varying levels of flammability, it is crucial to take appropriate safety precautions to protect yourself and your workspace. Here are some recommendations:

Avoid mixing incompatible materials: Certain glues and chemicals can react violently when mixed, leading to flammable gases or other hazardous substances. Use protective gear: Wear safety goggles, gloves, and a respirator when working with flammable materials to reduce the risk of inhaling harmful fumes or getting substances on your skin. Work in a well-ventilated area: Ensure your workspace has good air circulation to reduce the concentration of flammable vapors. Store materials properly: Keep all flammable substances, including glue, in secure, labeled containers, and store them away from direct heat sources like ovens or radiators.

By understanding the flammability of the glues you use, you can take the necessary steps to ensure your woodworking projects are both safe and successful. Whether you are a seasoned craftsman or a beginner, knowing the correct safety measures can make all the difference in protecting yourself and your materials.

Conclusion

The flammability of wood glue is a vital consideration for any woodworker. While some glues, like PVA and epoxy, are relatively safe and non-flammable, others like urethane and cyanoacrylate can pose a higher fire risk. By understanding the properties of these glues and taking appropriate safety measures, you can continue to enjoy the satisfaction of crafting beautiful wooden pieces while keeping yourself and your workspace safe.