How to properly glue a furniture board. Types of wood splicing, technological process and equipment Wooden lamellas for furniture joints

In the furniture industry, lamellas - small oval-shaped plates - have been used for many years: with their help, they give additional strength to the adhesive bond. But for the home master, lamellas have only recently become an alternative to spikes. After all, in order to use the lamellas, you need a tool that cuts the corresponding grooves in the details. Now there is such a tool. This is a modernized device for leveling the shadow joints of wood paneling, equipped with a set of interchangeable cutting discs, one of which is designed specifically for cutting longitudinal grooves.

The device is designed in such a way that it is extremely easy to use. The cutting disc does not need to be guided: the grooves are made automatically. It is also important that the position of the disk can be changed and thereby adjust the depth of the grooves. All this simplifies and speeds up the process of connecting parts, especially when compared with the processing required to secure the connection with plug-in spikes.

Another feature is that the grooves can be placed practically by eye: the quality of the connection will not suffer, even if the lamella “floats” a little in a slightly longer groove.

If you need to connect two boards or panels at a right angle, spikes (hidden or through) will secure the connection. Wooden rods have served and still serve as the main means of such fastening for home craftsmen. However, now you can put the lamellas into action.

How to cut grooves for slats

Based on the selected lamellas, determine the depth of the groove and adjust the position of the cutting disc accordingly. Then set the square so that the distance from it to the disk corresponds to half the thickness of the material being processed. Then the grooves will pass strictly in the middle of the end side of the part.

When processing the ends, the square rests on the outer surface of the part, which also facilitates the use of the device. When cutting grooves at the outer edge of another part, the square rests against its end. In order for the grooves on both parts to fit exactly to each other, you must first apply the markup.

The connection on the slats of the partition in the shelf or drawer is just as simple. The only difference is that when cutting grooves in the main parts, the square is not installed: it is replaced by the end edge of the partition itself, which is fixed on the workbench together with the main part with clamps.

Depending on the thickness of the material being processed and the dimensions of the product, lamellas of one size or another are selected.

The position of the cutting disc and, accordingly, the depth of cut can be adjusted. If necessary, a square is installed over the disk.

When cutting grooves at the outer edge of the part, the square rests against its end.

When cutting grooves at the end of the part, the square is on top of it. The groove does not have to run in the middle of the butt.

For T-shaped joints (when, for example, a partition is installed in a box), the grooves are cut without a square, which replaces another part. Special, thinner disks are used to align the shadow joints of the wooden sheathing.

Wood splicing along the length is increasingly used for the manufacture of large parts from wood. This allows significant savings in raw materials. In addition to saving materials, this method also improves the consumer qualities of wood - it is less susceptible to deformation. The use of high-quality glue makes it possible to glue pieces of wood without visible seams, which creates the illusion of a solid beam or board.

The connection of parts along the length is called splicing. Choose a method of splicing the board, depending on where the parts made from it will be used. For example, in the manufacture of a plinth that does not carry any load, the board is spliced on a mustache: the ends of the boards to be joined are cut at an angle of 45 degrees and overlapped with glue. There are several splicing methods:

a - stepped; b - on the mustache with blunting; in - stepped with a ledge; g - stepped on the mustache with bluntness; d - stepped with a ledge and wedges; e - stepped on the mustache with bluntness and wedges; g - back to back.

For products that will experience serious loads during operation, splicing on a spike (wedge-shaped or notched) is used. At the same time, due to the increase in the area of the parts to be glued, the connection receives increased strength, wood is economically used.

All defects on short pieces of spliced boards are removed - this is how rough blanks for splicing are obtained. Then they are connected into lamellas of the required length using a micro-thorn connection. The cutting of micro-studs is carried out with the help of special milling cutters on tenon-cutting units. As a result, a compound is obtained that has the ability to self-jam under the action of a press while maintaining the effect obtained. The process is controlled in accordance with GOST 6449, 1 - 82 “Products made of wood and wood materials. Tolerance fields for linear dimensions and fit.

Using the technology of longitudinal splicing from second-rate raw materials, blanks of the required length and high quality are obtained. For longitudinal splicing, automatic or semi-automatic lines are used, the most famous of them are the following: Dimter, Paul, Irion, Reinhardt, Grecon, Ledinek. In this case, the following requirements must be observed:

When splicing blanks, it is impossible to allow the interval between cutting the spikes and the splicing process itself to exceed one day.
The finished lamella spliced with the help of microthorns should not have gaps and cracks. Defects such as noticeable flaws on the planed side in the form of various holes and gaps indicate the presence of a marriage in the work.
The room intended for splicing should provide positive air temperature, not less than 16 degrees.
The moisture content of the glued blanks may differ by no more than 3%.
The moisture content of the finished lamella depends on the requirements of the consumer, but should be within the parameters of 6-14%.
According to GOST 10414-90 “Laminated solid wood. General requirements for toothed adhesive joints, end pressure when splicing coniferous and soft hardwoods - 8.0 MPa, hardwoods - 10 MPa.
The glue is applied with a special device, and the layer thickness should not exceed 0.1 mm. In the connection, the adhesive coating should occupy more than 0.8 of the tenon depth.
It is permissible to use an adhesive that complies with the international standards DIN EN204 "Non-structural thermoplastic adhesives for wood".
The product must be pressed no later than 2 minutes after applying the adhesive.
For a strong connection, pressing should last at least 5-6 seconds.
According to GOST 24700-99 No. Construction of buildings and structures. Blocks window wooden with double-glazed windows. Specifications” connection strength should be from 26 MPS and above.
It is necessary to clean the product of excess glue.
Before the next stage of processing, the product must be kept for at least a day (preferably two days) in a room with a temperature of 15 degrees. This will allow the glue to polymerize, and the moisture in the wood during this time can be evenly distributed.

Main types of defects

A quality joint provides the spliced lamella with the strength of the original wood and should not be very noticeable. If the technology is violated or the operator is careless, the following defects may be present in the finished product received from the splicing line:

Defect	Cause
There is an empty space between the spikes	Insufficient pressing or uneven application of adhesive
The resulting product does not have the required strength	Spikes received less than the required amount of resin (glue)
Stepping - the stepped surface of the finished part	Non-calibrated workpieces (of different thicknesses) are fed for splicing. The resulting product is rejected and used for further processing.
Screwing - the lamellas have sloped planes - the final product can be in the form of a propeller.	A poor-quality workpiece is obtained from the use of parts with conical planes or from incorrect initial machine settings, when a right angle between the plane of the cutting tool and the edge of the workpieces is not maintained. Permissible deviations per one meter of the workpiece in length is 3 mm, in width - 2 mm. These products are also recyclable.
Finished parts may have areas with torn-out wood fibers in the tenon joints.	Formed when working with blunt tools or violation of technology. Products with torn fibers are also rejected. Defective products are spliced again, achieving a quality product.

All spliced blanks must be aged for two to three days so that the glue used has time to polymerize and acquire working qualities. After exposure, the blanks are subjected to finishing processing and a completely ready-to-use product is obtained from it. The range of finished products may include painted floor slats, architraves, skirting boards, glued beams or glued boards.

The use of automatic and semi-automatic splicing lines allows you to find the use of off-grade or oversized wood and significantly expand the range of products.

The choice of splicing scheme depending on the load on the finished product

If the product will only be subjected to compression, then it is enough to apply the simplest type of splicing, connecting the parts to the overlay (oblique or straight cuts). To increase the resistance of the product under lateral loads, a connection such as an overhead lock is used. In this case, an overlay is made using beveled ends or with an end spike.

For products designed for tensile loads, rim lock connections (toothed or simple) are used. For its implementation, recesses and protrusions are cut out on the workpieces to be joined. The serrated rim lock scheme achieves a high connection strength that withstands compressive, tensile and lateral loads.

The “double frying pan” connection is a straight lining with a spike called a dovetail. Shows high strength under different loads - lateral displacements, tension and compression.

The “sliding lock” connection scheme in the form of an overlay with a beveled stop can give strength to a product subjected to tension and transverse loads.

There is a scheme in which increased rigidity of the design of overhead locks is achieved by driving additional wedges between the protrusions. Such locks are called tension. Make them either detachable or glued. Split tension locks should be oiled or painted to help protect the lock from moisture.

The choice of raw materials for the production of glued lumber

The quality of the final product is directly related to the quality of raw materials. Despite the fact that glued wood implies the use of off-grade waste, for a greater yield of quality products, there are still selection criteria for raw materials. You can also glue sawdust, but then it will be a completely different product. Since our task is to obtain high-quality lumber, in order to reduce the cost, when choosing raw materials, it is necessary to adhere to certain standards:

Wood with too many knots will require too much labor to prepare and most of it will be wasted. Therefore, we take only the wood of the first and second cuts.
We select blanks of such length that will make it possible to obtain an acceptable quality of the product. Cuts that are too short will increase glue consumption and reduce quality. Plus, a significant part of such raw materials will turn into sawdust during the manufacturing process.
Accept wood for processing with an allowance, the size of which excludes the formation of additional production waste.

The correct splicing technology includes the entire production cycle. Everything matters, from the right places for raw materials and semi-finished products to the quantity and quality of manufactured products and the percentage of waste.

Technological cycles of wood splicing processes

The whole cycle includes the following steps:

Selection and sorting of raw materials;
Drying lumber selected for splicing;
Rough processing for leveling raw materials;
Removal of raw material defects;
Trimming and making spikes for joints;
Sorting of received lamellas;
The splicing process itself - laying, gluing, pressing;
Exposure of spliced products until complete polymerization of the adhesive;
Finishing of finger-jointed wood.

Lumber after sorting and drying to a moisture content of 8-16% enters the shop for the production of finger jointed wood. There is a delivery in wood packages with and without gaskets. When delivering packages with gaskets, it becomes necessary to introduce an additional operation - removing wood from the gaskets. In a particular case, it all depends on the chosen technology.

The next step is roughing. Required for leveling surfaces on all sides. The main task is to remove the irregularities that have arisen in the process of drying lumber from warping. After roughing, small defects are allowed in the form of insufficiently high-quality chips. Next, we remove those defects that will affect the quality of the final product. We get a new lamella, ready for further processing.

Depending on what type of product is expected to be obtained at the output, the technologist gives an indication of the nature of the defects that must be cut out of the blanks or sorted to obtain cheaper materials. So, glued wood for painting may contain more defects than high-quality glued laminated timber or a board:

blue;
knots;
resinousness;
the presence of wane;
other types of damage.

Trimming of lamellas occurs in automatic or semi-automatic mode. Automatic mode involves cutting parts according to a given program. When working in semi-automatic mode, the task of the machine operator is to distribute into which pocket to direct this or that lamella for trimming.

In order to use wood to the maximum, lamellas with defects are glued together according to the technology - one side of the finished product (front) should not contain defects, and all defects should be on the wrong side of the product. To do this, it is important not to make a mistake when arranging the spliced material. Also act in the presence of wane. The lamellas are laid so that all the wane parts are on one of the ends of the finished product.

In the workshop for each type of lamella there should be a specially designated storage area.

All received lamellas are stacked according to grades on pallets and signed. This approach allows you to clearly monitor the production process. Splicing of lamellas is carried out only after the accumulation of volumes sufficient for the work of the shift. In other cases, this is irrational, as it requires a lot of unnecessary operations to rearrange equipment and raw materials.

In the production of glued laminated lumber, losses inevitably occur when cutting tenons for joining and when cutting finger-jointed lamellas to the finished size. It is much more profitable to produce products of greater length, since this significantly reduces the amount of waste.

Gluing furniture panels is carried out not only on an industrial scale. This technology is used by home craftsmen to make furniture that is not inferior in strength to solid oak structures. Spliced lamella countertops last a very long time, do not warp, deform or swell from moisture. Another reason for splicing is the presence of small bars, which are unreasonable to throw away, but there is nowhere to apply them. The best option is to glue the lamellas into furniture boards.

Do-it-yourself furniture made from natural and environmentally friendly materials is valued and in high demand. This structural material is more attractive and practical than MDF and chipboard.

How to glue a furniture board at home. Preparation for work

To get an aesthetic and high-quality material, sort the bars according to the following criteria:

absence of knots and cracks on the surface;
correct geometry (slight curvature can be leveled with a planer);
compliance with the texture pattern and shade;
breed identity - pine sticks together with pine, larch with larch.

Photo 1. Joinery shop "LesoBirzha"

Furniture board gluing technology

How to glue a furniture board? The answer to this question depends on the scale of home production. If the work is planned to be one-time for your own needs, you can use the improvised tool available to each owner.

If you want to organize a small furniture manufacturing business, you will have to acquire several machines:

planing;
grinding belt;
surface grinding;
band saw;
milling.

Please note that the dimensions of the finished product are slightly smaller than the blanks. Make an allowance for finishing the ends. The width of the lamellas to be joined should be no more than 15 cm. Only with such dimensions can the absence of internal stress of the wood be achieved.

Photo 2. Spliced larch furniture board

For furniture, the optimal thickness of the panels is 20 mm. However, according to the rules for gluing furniture panels, you need to choose blanks with a thickness of 25 mm. Extra 5 mm are removed in 2 steps. Before splicing, 3 mm are removed, the remaining 2 mm are removed during the final processing.

What kind of glue to glue furniture boards

Mostly furniture boards are glued together with D-1 glue. This glue is produced with varying degrees of water resistance.

There are several water resistance groups in the international classification, the domestic industry uses four:

low;
two middle ones - A and B;
high.

However, at home, any glue for wood is suitable. If you do not want to use PVA, take the "Joiner" adhesive.

Photo 3. Thin pine furniture board

How to properly glue a furniture board. Lamella arrangement options

Long lamellas are spliced only in width. If you are working with small bars, they should be staggered. In this case, both long and short end parts are lubricated with glue.

With two-layer gluing, the bars of the first row are perpendicular to the bars of the second row. These shields are extremely strong and durable. Still raw blanks are placed under the press, where they should be until the glue dries completely. This is followed by careful grinding on special equipment and chamfering on a milling machine. After finishing, the joints disappear, the panels are ready for sawing into parts.

Photo 4. Larch furniture board

How to glue two furniture boards together

The need to connect two panels into one arises in the manufacture of products of non-standard width. 600 mm is the maximum sheet standard, so you will not find a larger width in all online stores. How to glue furniture boards to get one wide one from two narrow boards? This question is often asked by clients to technologists of the LesoBirzha company.

Photo 5. Pine furniture board for furniture production

You can connect two plates with the help of grooves and a mortgage rail. In the adjacent ends, it is necessary to cut longitudinal grooves with a narrow cutter and place a rail lubricated with glue there. The ends of the panels also need to be thickly smeared with adhesive. There are several effective ways to glue wood panels. However, a professional carpenter will do the job best.

On the Stankoff.RU website you can buy wood splicing equipment from leading manufacturers. Available and on order more than 77 models of machines for wood splicing along the length at the best prices. Only profitable offers with detailed descriptions and photos. Check prices with managers.

Application and features of the technological process

The use of the technology of combining processed short-length blanks in the manufacture of lumber with specified parameters can significantly increase the profitability of woodworking production. Industrial wood splicing equipment is used in the complex process of creating quality products that are not inferior in strength to solid wood elements.

The machines are designed to connect individual parts of wood into a monolithic workpiece that does not have visible seams. Modern splicing technologies make it possible to achieve the complete illusion of a solid wood mass and guarantee the long-term reliability of the product. The work is carried out using automatic or semi-automatic complexes, including machines for performing sequential tasks:

Roughing. Elimination of defects in the form of resin inclusions and knots. Timber alignment.
Trimming work using milling to form butt joints of the required configuration.
The process of splicing bars, including laying, gluing and pressing the material until the adhesive composition is completely polymerized.

After each stage, the parts are sorted in accordance with the standards of the terms of reference. At the end, surface finishing and packaging of finished products are carried out. From the lamella obtained on a machine for splicing along the length of short-length parts, molded products, lining, floorboards, elements of entrance and window groups are made. Installations allow to regulate the parameters of work with the utmost precision and create finished products with a uniform texture and surface color.

The principle of operation of different types of equipment and splicing methods

automated models of equipment for splicing along the length or thickness of wooden elements prepared for the process includes working units:

for loading blanks;
cutting spikes;
application of adhesive composition;
moving parts to the press;
pressing module.

Machines that receive parts after processing at auxiliary installations load the material with preliminary joining of the parts, and alternately transfer the workpiece to the glue-applying and crimping device. Adjustment of the length of the spliced lamellas and the force during compression of the elements is carried out by special mechanisms. The highest productivity in work is shown by two-channel models, which allow to perform simultaneous set and pressing of workpieces on different working lines.

Interstate standards define the general requirements for adhesive joints of a toothed nature, according to which, when operating a wood splicing machine, the norms of specific end pressure must be observed. Depending on the load on the wooden elements during operation, wood splicing is carried out using different methods that allow the parts to withstand longitudinal or transverse compression:

oblique cutting along one and a half;
stronger connection using the "oblique mustache" technology;
direct pad with fastening.

The wood waste generated during the pre-treatment process is used for the manufacture of pressed products. The equipment is characterized by an extremely low percentage of rejects, which becomes possible only as a result of incorrectly adjusted press pressure or insufficient thickness of the adhesive applied. The correct settings of the machine operation provide the extremely accurate geometric shape of the products and the impeccable cleanliness of the smooth surface.