How to find Proper Glue color for repairing furniture
Choosing a glue for repairing furniture would be easy if all you had to do was pick out one that included wood among the many materials it bonds. But the array of glues available today can be quite bewildering, and choosing the right one is not so simple. Yet, if you stick to a brown, white or yellow liquid glue, all of which come in plastic containers, and refrain from using transparent glues, epoxies, miracle and wonder type glues, you won’t go too far wrong.
Workers in the wood of a bygone era had no choice of adhesives. But it didn’t much matter, for animal glue served them well. This type is still available in a granular form and some furniture builders and restorers – purists, especially – swear by it. But it is not convenient for the occasional home repair.
Today, brown glue (made only from animal hides) comes in ready-to-use liquid forms, and is handy and ideal for repairs to old furniture. For good results, this glue should be used when and where it is 70 degrees or warmer, so it will set slowly and not gel.
Hide glue adheres better to old hide glue than the white and yellow glues do to their old selves. This is important where access for cleaning is limited, particularly old veneer that is lifting at the edges. It is a simple business to slip some hide glue between the veneer and the groundwork, using a strip of stiff thin plastic. Heating the glue slightly by placing the container in a bowl of warm water will help it spread more readily.
Never use a contact cement to reattach veneer. The layers of glue dry too thickly to permit the veneer to lie down at its original level. Once stuck, the join cannot be separated.
For general breaks and repairs, many woodworkers prefer the white or yellow glues, declaring they are quicker setting, grab better and make a stronger bond. But both these and hide glue should produce a bond stronger than the wood itself when applied according to the manufacturer’s instructions, so the question of strength is hardly an important consideration in choosing a glue.
Both white and yellow glues rely on their strength on the wood being porous enough to extract moisture from the glue, thus reducing the thickness of the layer and bringing the two parts more closely together. This ”grabbing” quality is the reason these glues are popular for repairing fractures exposing the clean fresh wood.
The gap-filling quality of a glue refers to how well it will fill in and make up for the absence of close-fitting surfaces. But this is always limited. Certainly such a glue would be able to take care of a slightly loose-fitting dowel, but do not expect it to be able to make up for wood lost to careless preparation.
When regluing joints, clear areas of old glue, dirt and wax. But be careful to scrape off old glue without whittling away any of the wood.
A good glue also should be water soluble, making disassembly and the cleanup of excess glue easy. The former is important because no structural join in furniture should be irreversible. When set, the brown, yellow and white glues can be dissolved with warm water, though some think it helps to add an equal amount of household vinegar to the water.
To dissolve the glue, apply the water with a fine-tipped brush along the line of the join and let it soak in. Renew the liquid from time to time, wiping excess from the surface. As the glue softens, apply gentle pressure where practical on both sides of the join to ease it apart slightly and allow the liquid to seep further down. If old glue does not respond to this treatment, try lacquer thinner, but be careful to keep it away from finished surfaces, which it may soften.