Types of wood glue and features of its use

For a strong connection of wood products and materials based on it - wood boards, hardboard, cardboard - carpentry glue is used. The main role is played by protein - it is he who determines the strong bonding. The connection is very durable. With the gradual destruction of the structure, it is evident that not the adhesive layer is modified, but the adjacent layers of the tree. Such glue has a natural basis, does not emit harmful substances, therefore its use is completely safe even in children's rooms.

Types of wood glue

For the manufacture of glue, organic raw materials are used. Depending on the origin, the following types are distinguished:

• bone;
• hairline;
• fish.

Bone wood glue is the most common. It is obtained from the bones and bone waste of animals. Granules made from horns are especially appreciated. Bone glue contains gelatin, collagen and cysteine. All of them have excellent viscosity and allow solid bonding of wood products. Bone glue is usually sold in the form of granules.

The glue is made from leather industry waste. This is mainly mezra - a layer of subcutaneous tissue, which is cut off when dressing skins. Skin trimmings are also involved. All of them contain oligopeptides with sticky properties. The glue is produced in the form of tiles, flakes, powder.

Fish glue is prepared from scraps of fish: bones, heads, scales, entrails, fins. This glue is considered the highest quality, so it is the most expensive. It is used in the restoration of antique products, as a basis for icon painting, for other works requiring the highest quality. Fish glue can glue both homogeneous and heterogeneous surfaces. They release it in the form of granules or flakes.

PVA

PVA glue stands apart. It is fully synthetic. It is based on a substance called polyvinyl acetate. But PVA is safe, like its protein counterparts. It is even approved for use in educational institutions for children's creativity. For carpentry and construction work, PVA is also actively used. He copes with the combination of wood products, cardboard, wood boards.

Advantages of PVA glue:

• elasticity;
• moisture resistance;
• reliable adhesion of surfaces;
• transparency upon drying;
• affordable price;
• sold as a ready-to-eat mass.

Cooking features

Joiner glue is sold dry. Most often these are yellow-brown granules of a small size. Sometimes you can find glue in the tiles. Quality can be determined by appearance: the lighter and more transparent the granules, the better the glue.

Before using the glue, it is important to properly prepare. If you bought a tile, you need to grind it. To do this, wrap it in cloth and break it with a hammer to the state of crumbs.

The preparation of glue is divided into two stages.

1. Soak. Pour granules or chips with cold water. It must first be boiled, because the salts contained in the "raw" water will adversely affect the quality of the finished mass. The liquid should completely cover all the granules. Soak glue until it becomes soft, gelatinous. Soaking lasts from 4 to 12 hours, depending on the number of granules.
2. Cooking. After swelling, the glue should be boiled for about 15 minutes in a water bath. Maintain a temperature of 60 to 80 degrees. As a result, a homogeneous, without lumps, liquid should be obtained.In no case do not heat the mass over an open fire and bring to a boil - the protein from which the granules are made begins to break down, and the adhesive ability decreases. When a thin film forms on the surface, the adhesive mass is ready.

Gluing readiness can be checked in another way. Raise a stick over the surface that has been inhibited by the substance. If the liquid drips from it in separate drops - you need to cook more. If it flows continuously, the glue is ready.

For cooking wood glue there is a special device - a glue. It consists of two vessels of different sizes inserted into one another. Water is poured into a large container, and swollen carpentry glue is poured into a smaller one. Then a small vessel is placed inside a large one, and it, in turn, is put on fire. The best material for making buttercloths is copper.

Tip

Klejanka can be made independently by taking two containers of different sizes. For example, a large tin can serve as an external vessel. And the inside will be a small tin can mounted on a wire.

How to improve the properties of glue?

To improve some properties, at the preparation stage, you can add some other substances - the adhesive mass will become more versatile. It can be used to connect not only wooden, but also other surfaces.

• Drying oil. Add 10 g of linseed oil or natural drying oil to 40 g of granules. This will increase the moisture resistance of the adhesive joint.
• Glycerol. Add it at the rate of two teaspoons per liter of finished glue. Glycerin is added if you want to glue the skin.
• Wood ash, chalk powder. Sift one of the two powdered masses and add to the finished glue. This will result in excellent putty paste.
• Ammonium chloride, borax, phenol. These additives are antiseptics, they will protect the seam from mold.

Useful Tips

Protein-based glue has its own characteristics. Those who use it for the first time do not always know them. Below are a few tips to make this material easier to use.

• To maintain the desired consistency, you need to add hot boiled water (if you want to make the mass more liquid) or increase the cooking time (if you need a thicker mass).
• The ideal working temperature is from 30 to 70 degrees. In a buttercloth at an ambient temperature of about 25 ⁰With adhesive retains suitability for two hours. When the adhesive mass becomes too cold, it thickens and the adhesive properties decrease.
• Ready joiner's glue is not subject to storage. Therefore, it will be necessary to soak and cook exactly as many granules as necessary for the current work. On the second day, the ability to glue becomes much lower. And after three days, mold is likely to appear. Since protein raw materials serve as the basis, rotting and decomposition, accompanied by a characteristic odor, are not ruled out.
• The thickness of the adhesive layer should not exceed 0.2 mm.

There is also casein glue. It consists of kerosene, sodium fluoride, casein, copper sulphate and slaked lime. This species is rarely used, since it is poorly stored, when dried, it significantly decreases in volume and changes color.

Terms of use

The procedure for working with wood glue is somewhat different from the use of its synthetic analogues (for example, PVA, which is also intended for gluing wood and cardboard).

1. Prepare the adhesive mass according to the above algorithm. Watch the temperature.
2. Keep bonding parts dry. Permissible humidity of wood products is not more than 10%. The maximum humidity of the veneer should not exceed 5%.
3. With a bristle or bast brush, apply the adhesive mass evenly on both surfaces. The total thickness of the seam should be no more than 0.1-0.2 mm.
4. Wait 2-5 minutes until the glue dries slightly and cools. So it will be squeezed out less when connecting parts.
5. After connecting the two surfaces, gently rub them together.
6. Tie the glued parts together tightly with twine or squeeze with a clamp.
7. You can use the glued thing after six hours.

When gluing the ends, the glue can be applied in two layers. Be sure to let the first coat dry before reapplying.

How to choose wood glue?

When choosing carpentry glue, be guided by the following criteria.

• Color and transparency. The lighter and more transparent the granules or tiles, the better the glue.
• Type of glue. It directly depends on the type of work. The best and most expensive is fish. It is used for delicate and restoration work, where the highest demands are placed on quality. For ordinary repairs, bone or mesenteric ones are suitable.

The plus of all the above types of wood glue is their absolute safety. For construction needs, it is better to stay on bone, glue or PVA glue. They provide strong bonding and are affordable. For fine work and restoration, glue from fish raw materials is ideal. And the above tips for preparation and use will help you quickly and effectively cope with the task.