Some information on the various cabinetmaking glues

Cabinetmaking glue

Whatever the glue, to have a correct result, surfaces must be clean and adjusted.
Any trace of modern cleaning product, any bad choice of previous bond would condemn or at least compromise in time the bonding that you would do today.
It is therefore essential to think carefully before acting.
We will list the main glues used in cabinetmaking.

An adhesive is a product of liquid or gelatinous nature that allows to assemble parts between them. There are two types of glue  :

• Glues of animal origin  : obtained by baking collagen-rich materials: rabbit skin glue, bone glue, nerve glue, tendon glue, glue fish They have the particularity of being reversible (moistening with a mixture of one-third of alcohol at 95 ° and two-thirds of water).
  The veneer, it can take off with a damp cloth and an iron.

• Synthetic glues  : these are modern glues: vinyl (white glue), neoprene, cyanoacrylate ...
  These glues are mostly irreversible, so you have to use with the utmost circumspection.

BONE GLUE

A little history

Without doubt the oldest glue, it was used under ancient Egypt, nearly 4000 years. It is extracted from cattle bones that have been boiled for a long time, then filtered and dried on grids, to be marketed in the form of plates.

Today it is only found in pearls. The more pure and transparent the glue, the better it is.

What does the old dictionary say  ?

Strong glue, carpenter's glue, bone glue.
Prepared by hot processing of bones, skins and cartilage, then concentrating the broths obtained and drying. Brown, translucent, brittle plates or rounded granules.

Swells in cold water, dissolves hot, insoluble in alcohol, insolubilized by tannin. The concentrated aqueous solution is jellied by cooling: it is used as an adhesive in carpentry, cabinetry, cardboard.

To this day ...

Bone bone glue is ready for use. It is not necessarily necessary to add nerve glue powder, but if necessary, it will dose, for common use, as follows: 2/3 of bone for 1/3 of nerve. Mix everything in a container (not iron) going to a bain-marie. Swell the glue (pour about 1 cm of water over the glue) overnight, then put in a water bath at 60 ° until completely dissolved, foam, the glue is ready.

Disassembly is possible by heating at about 60 °. It is therefore suitable for plating and marquetry, because it is easily reversible and therefore gives the furniture a chance to be restored properly.

FISH GLUE

A little chemistry  !

Gelatin is obtained by the hydrolysis of collagen, which is the main protein found in skin and bones. The raw material is the skin of deep-sea fish such as cod, haddock and Pollock. The uniqueness of fish gelatin lies in the amino acid content of gelatin. Although all gelatins are composed of the same 20 amino acids, there may be a variation in the amount of imino acids, proline and hydroxyproline. With lower amounts of these imino acids, there is less binding of gelatin hydrogen in water solutions, and consequently a reduction in the gelation temperature. Gelatin from cod skin gels at 10 ° C, while gelatin from carp skin would be more similar to animal gelatin, which gels above room temperature. Most people think of gelatin as an additive or part of a photographic film. With a lower gelation temperature, other commercial applications of fish gelatin have been developed. These applications are discussed.

In summary ...

Very good glue for assemblies, used in various fields. Yellow caramel, it does not stain the wood and browns on drying. It is the animal glue with the longest drying time, and is therefore used with clamps for a period of at least twelve hours. The temperature of use must be higher than 14 °, otherwise its consistency is too pasty to be spread.

Nerve glue

The nerve glue is extracted from the nerves of cattle, in the same way as the bone glue. It is used to provide flexibility to the latter. For wood, difficult to use pure, because this same flexibility would make it ineffective. On the other hand, in particular fields such as archery, it alone fulfills its function perfectly.

Rabbit skin glue

It appears around the 16th century. It also has a very fast take of about 5 minutes. This glue is used for gilding, priming and painting colors.

White glue (vinyl)

It is used for assembling wood on wood furniture today. Do not use on old furniture assemblies that were originally made with bone glue, otherwise remove all traces of it. Indeed, it has no adhesion on animal glues, and then performs a function of "wedging" and not sticking. In addition, this glue does not support thick joints, so it is perfect for machine assemblies, for very cleanly planed wood, because it only plays its role as pore to pore without glue film between the two elements. The use of a clamp to achieve this is absolutely essential. Depending on the brands, the types, it can be used outdoors, indoors, withstand frost or not, and set drying times from one hour to four hours.

Neoprene glue

It is a contact adhesive, that is to say that the two faces to be assembled separately, then after a drying of about 10-20 min, the two elements are manually tightened. The adhesive film must be dry to the touch before contacting. Its setting is instantaneous, but the final hardness is obtained after 72 hours. Very practical to use, it is essential for plating modern materials such as formica, plastic sheets, chipboard, etc ..., but also leather, rubber. It is a flexible glue, so ideal for soft collages. To proscribe absolutely for the wood and the old furniture. It is the obsession of cabinetmakers to find assemblages glued to neoprene, or even worse marquetry. This is very common and very bad   !!!

Cyanoacrylate glue

Advertising this glue is more to do !! A few drops, and an elephant sticks to the ceiling of your living room. Of exemplary solidity, it is however irreversible. It is ideal to put everything hard (porcelain, iron, etc ...), but disastrous on antique furniture.It must use this glue with caution, because the vapors are dangerous for health, and a drop would be enough to make you lose the view in case of projection.

Araldite glue

Araldite is the registered name for a two-component adhesive consisting of an epoxide and a hardener, mixed at 50/50. It is an extraordinary way to pick up marble, ceramics, iron. More flexible than super glue, it is much stronger. Several types exist, ranging from 1 minute of drying to 8 hours. The longer the time, the stronger the bonding. This glue has in addition the enormous advantage of being tinted in the mass with natural pigments, and thus make the glue joint invisible. It is also excellent for wood, provided it is used intelligently: perfect to make a splice on a foot, for example, because it will never be useful to undo such a repair during a restoration, moreover it does not fear neither the water, nor the gel, so not the unhappy mop ... but beware, it is out of the question to use on an assembly or on veneer, because it would definitely condemn any future intervention on it. This is probably the strongest bonding medium that exists today.