Hide glue is a traditional adhesive that has been used in woodworking and other crafts for centuries. It is derived from collagen taken from animal hides, bones, or hooves, which is then processed into a gelatinous substance. This type of glue has unique properties and applications that make it the ideal choice for specific uses, particularly in fine woodworking, antique restoration, and musical instrument repairs.
Hide glue comes in dry granules called ‘pearls’, as a coarse powder, or in a pre-made liquid form. The dry forms need to be mixed with water and heated in a double boiler to achieve the right consistency before use. It is important to control the temperature carefully, as overheating can degrade the glue's strength. Once prepared, it should be used fairly quickly to ensure best results.
Liquid hide glue is the same collagen as the dry form but it includes a small amount of additives that keep the glue liquid at room temperature. It therefore needs no specialised preparation before use. On cold days, it can be gently warmed to make it runnier.
One of the most significant properties of hide glue is its reversibility. It can be softened or dissolved with moisture and heat, making it an excellent choice for applications where future disassembly or repair might be necessary. This feature is particularly valued in the restoration of antiques and musical instruments, where preserving the integrity and authenticity of the original materials is crucial.
Once set, hide glue forms a strong bond that is less likely to creep under pressure compared to some modern adhesives. It also does not affect the finish of the wood, making it ideal for use in fine furniture making.
Hide glue is often used in the construction of fine furniture due to its strong bonding properties and ease of application. It is especially useful in joinery such as dovetails, mortise and tenon joints, and for veneering.
Because hide glue can be reversed and does not leave damaging residues, it's a preferred choice for restoring antique furniture and repairing valuable wood items where maintaining authenticity is important.
Luthiers use hide glue extensively in the making and repairing of stringed instruments like violins and guitars. Its reversibility allows for easy disassembly for repairs, an essential feature in high-quality instrument maintenance.
Hide glue is also used in bookbinding because of its flexibility and long-term durability. It remains a popular choice for binding books that need to withstand the test of time.
Advantages and Disadvantages
Advantages
Reversible: Can be remelted and adjusted or completely removed with heat and moisture.
Natural: Made from natural materials, it is non-toxic and environmentally friendly.
Historical authenticity: Ideal for restoration work where maintaining the original materials and methods is essential.
Disadvantages
Temperature sensitive: Performance can be compromised in very hot or humid conditions.
Longer setting time: May require longer clamp times compared to modern synthetic adhesives.
Potential for degradation: Being organic, it can deteriorate and lose effectiveness over time if not properly stored.
Storage
Dry hide glue granules have a long shelf life if kept dry and sealed, but once prepared, it should be refrigerated and used within a few weeks to maintain its effectiveness. Liquid hide glue will keep in the bottle for a couple of years.
To test whether your hide glue is still useable, put a small amount on your thumb and rub it between thumb and forefinger until most of the glue is squeezed out. Pull your fingers apart multiple times and if the glue is good you will see threadlike filaments forming between the surfaces of your fingers.
Overall, hide glue remains a popular choice for many artisans who appreciate its unique properties and historical significance in craft and woodworking. To read more about Titebond Liquid Hide Glue, click here.