In the furniture industry, lamellas—small oval-shaped plates—have been used for many years: with their help, they add additional strength to the adhesive joint. But for home handyman lamellas have only recently become an alternative to studs. After all, in order to use lamellas, you need a tool that cuts the corresponding grooves in the parts. Now there is such a tool. This is a modernized device for aligning shadow joints in wood sheathing, 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 joining parts, especially when compared with the processing required to secure the connection with insert tenons.
Another feature is that the grooves can be positioned almost 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 right angles, tenons (secret or through) will secure the connection. Wooden rods were and still are the main means of such fastening for home craftsmen. However, now you can put the lamellas into action.
How to cut grooves for lamellas correctly
Using the selected lamellas, determine the depth of the groove and adjust the position of the cutting blade accordingly. Then install 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 along 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 makes it easier to use the device. When cutting grooves at the outer edge of another part, the square rests against its end. To ensure that the grooves on both parts fit exactly together, you must first apply markings.
The connection to the lamella of the partition in a 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 along 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 on top of 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 a part, the square is on top of it. The groove does not have to run through the middle of the end.
For T-shaped connections (when, for example, a partition is installed in a box), the grooves are cut without a square, which is replaced by another part. To align the shadow seams of wooden cladding, special, thinner discs are used.
Gluing of furniture panels is carried out not only on an industrial scale. Home craftsmen resort to this technology to make furniture that is as durable as solid oak structures. Tabletops made from spliced lamellas last a very long time, do not warp, deform or swell from moisture. Another reason for splicing is the presence of small-sized bars, which are unreasonable to throw away and have nowhere to use. The best option is gluing the lamellas into furniture panels.
Furniture made from natural and environmentally friendly materials with your own hands is valued and in high demand. The construction material more attractive and practical than MDF and chipboard.
How to glue furniture board at home. Preparing for work
To get 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 plane);
- correspondence of texture pattern and shade;
- identity of the species - pine is glued to pine, larch to larch.
Photo 1. Carpentry shop "LesoBirzha"
Furniture board gluing technology
How to glue 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 available tools available to each owner.
If you want to organize a small furniture manufacturing business, you will have to acquire several machines:
- planing;
- sanding belt;
- surface grinding;
- band saw;
- milling
Please note that the dimensions of the finished product are slightly smaller than the blanks. Make allowance for finishing the ends. The width of the spliced lamellas should be no more than 15 cm. Only with such dimensions can the absence of internal tension in the wood be achieved.
Photo 2. Finger-joined furniture panel made of larch
For furniture optimal thickness panels is 20 mm. However, according to the rules for gluing furniture panels, you need to choose blanks with a thickness of 25 mm. The extra 5 mm is removed in 2 steps. Even before splicing, 3 mm is removed, the remaining 2 mm are removed during the final processing.
What glue to use to glue furniture boards
Basically, furniture panels 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; domestic industry uses four:
- low;
- two middle ones - A and B;
- high.
However, any wood glue will do at home. If you don’t want to use PVA, take the “Stolyar” adhesive.
Photo 3. Thin pine furniture panel
How to properly glue furniture panels. Slat arrangement options
Long lamellas are spliced only along the width. If you are working with small bars, they should be arranged in a checkerboard pattern. In this case, both the long and short end parts are lubricated with glue.
With two-layer gluing, the bars of the first row are located perpendicular to the bars of the second row. Such shields are particularly strong and durable. Still raw blanks are placed under a press, where they should remain until the glue dries completely. This is followed by thorough grinding using special equipment and chamfering milling machine. After finishing the joints disappear, the panels are ready for sawing into parts.
Photo 4. Furniture panel made of larch
How to glue two furniture panels together
The need to connect two panels into one arises when manufacturing products of non-standard width. 600 mm is the maximum standard for sheets, so you won’t find a wider width in all online stores. How to glue furniture panels to make one wide one from two narrow panels? Clients often ask this question to LesoBirzha technologists.
Photo 5. Furniture board made of pine for furniture production
You can connect two slabs using grooves and a laying strip. At the contacting ends, it is necessary to cut longitudinal grooves with a narrow milling cutter and place a strip coated with glue there. The ends of the panels also need to be thickly spread adhesive composition. There are several effective ways gluing wooden panels. However, the task is best handled by a professional carpenter.
Lengthwise splicing of wood is increasingly used for the manufacture of large wooden parts. This allows you to significantly save 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. The method of joining the boards is chosen depending on where the parts made from it will be used. For example, when making a plinth that does not carry any load, the boards are spliced together: the ends of the boards to be joined are cut at an angle of 45 degrees and overlapped using glue. There are several splicing methods:
a - stepped; b - on a mustache with bluntness; c - stepped with a protrusion; g - stepped on a mustache with blunting; d - stepped with a ledge and wedges; e - stepped on a miter with bluntness and wedges; Well - back to back.
For products that will experience serious loads during operation, tenon splicing (wedge-shaped or toothed) is used. At the same time, by increasing the area of the parts to be glued, the joint gains increased strength, and wood is used economically.
All defects on short pieces of joined boards are removed - this is how rough blanks for joining are obtained. Next, they are connected into lamellas of the required length using a micro-spike connection. Micro-tenons are cut using special cutters on tenon-cutting units. The result is a compound that has the ability to self-jam under the action of a press while maintaining the resulting effect. The process is subject to control according to GOST 6449, 1 – 82 “Wood products and wood materials. Tolerance fields for linear dimensions and fit.”
Using longitudinal splicing technology, blanks of the required length are obtained from second-grade raw materials and High Quality. For longitudinal splicing, automatic or semi-automatic lines are used, the most famous of which are the following: Dimter, Paul, Irion, Reinhardt, Grecon, Ledinek. In this case, the following requirements must be observed:
- When splicing workpieces, the interval between cutting the tenons and the splicing process itself must not be allowed to exceed one day.
- The finished lamella spliced using microspikes should have no gaps or cracks. Defects such as noticeable flaws on the planed side in the form of various holes and gaps indicate the presence of defects in the work.
- The room intended for splicing work must ensure a positive air temperature of no less than 16 degrees.
- The humidity of the glued workpieces may differ by no more than 3%.
- The humidity 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 “Massive laminated wood. General requirements for serrated adhesive joints" end pressure when splicing coniferous and soft hardwoods is 8.0 MPa, hard wood is 10 MPa.
- The glue is applied with a special device, and the layer thickness should not exceed 0.1 mm. In a joint, the adhesive coating should occupy more than 0.8 of the depth of the tenon.
- It is permissible to use glue that complies with international standards DIN EN204 “Non-structural thermoplastic adhesives for wood”.
- The product must be pressed no later than 2 minutes after applying the glue.
- For a strong connection, pressing should last at least 5-6 seconds.
- According to GOST 24700-99 No. Construction of buildings and structures. Wooden window blocks with double-glazed windows. Specifications» the strength of the connection should be 26 MPS and higher.
- It is necessary to clean the product from 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 can be evenly distributed during this time.
Main types of defects
A high-quality connection 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 inattentive, the following defects may be present in the finished product received from the splicing line:
| Defect | Cause of occurrence |
|---|---|
| There is empty space between the spikes | Insufficient pressing or uneven application of the adhesive composition |
| The resulting product does not have the required strength | The spikes received less than the required amount of resin (glue) |
| Stepping - stepped surface of the finished part | Uncalibrated workpieces (of different thicknesses) are supplied for splicing. The resulting product is rejected and used for further processing |
| Helicality - the lamellas have planes with a slope - the final product can have the shape of a propeller. | Poor-quality workpieces are obtained from the use of parts with conical planes or due to incorrect initial settings of the machine, when the right angle between the plane is not maintained cutting tool and the edge of the workpieces. Permissible deviations per meter of workpiece the length is 3 mm, the width is 2 mm. These products are also recyclable |
| Finished parts may have areas with torn wood fibers in the tenon joints. | Formed when working with blunt instruments or violating technology. Products with torn fibers are also rejected. Defective products are spliced again to achieve a high-quality product. |
All spliced workpieces must be left to rest for two to three days so that the glue used has time to polymerize and acquire working qualities. After aging, the workpieces are subjected to finishing processing and a product completely ready for use is obtained from it. The range of finished products may include painted floor slats, platbands, skirting boards, laminated veneer lumber or laminated boards.
The use of automatic and semi-automatic splicing lines makes it possible to find use for off-grade or oversized wood and significantly expand the range of products.
Selecting a splicing scheme depending on the load on the finished product
If the product will only be subjected to compression, then it is enough to use the simplest type of splicing, connecting the parts with an overlay (oblique or straight cuts). To increase the resistance of the product under lateral loads, a rim lock type connection is used. In this case, an overlay is made using beveled ends or with an end tenon.
For products designed for tensile loads, padlock connections (notched or simple) are used. To perform it, recesses and protrusions are cut out on the workpieces to be joined. The serrated rim lock design allows for high joint strength that can withstand compressive, tensile and lateral loads.
The double pan joint is a straight overlay with a tenon 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 impart strength to a product subject to tension and lateral loads.
There is a scheme in which increased rigidity of the structure of overhead locks is achieved by driving additional wedges between the protrusions. Such locks are called tension locks. They are made either detachable or glued together. Detachable tension locks should be oiled or painted, which will help protect the lock from moisture.
Selection of raw materials for the production of laminated lumber
The quality of the final product is directly related to the quality of raw materials. Despite the fact that laminated wood involves the use of off-grade waste, for a greater yield of high-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 goal is to obtain high-quality lumber, in order to reduce costs when choosing raw materials, we must adhere to certain standards:
- Wood with too many knots will require too much labor to prepare and much of it will be wasted. Therefore, we take only wood from the first and second cuts.
- We select blanks of such length that will make it possible to obtain acceptable quality of the product. Trims 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.
- For processing, accept wood with an allowance the size of which eliminates the formation of additional production waste.
The correct splicing technology includes the entire production cycle. Everything matters, from the correct locations for raw materials and semi-finished products to the quantity and quality of manufactured products and the percentage of waste.
Technological cycles of wood joining processes
The entire cycle includes the following steps:
- Selection and sorting of raw materials;
- Drying of lumber selected for joining;
- Rough processing for leveling raw materials;
- Removal of raw material defects;
- Trimming and making tenons for joints;
- Sorting of received lamellas;
- The splicing process itself – laying, gluing, pressing;
- Conditioning of spliced products until the glue is completely polymerized;
- Finishing of jointed wood.
The lumber, after sorting and drying to a moisture content of 8-16%, enters the workshop for the production of jointed wood. There is delivery in packages of wood 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 stage is rough processing. Necessary for leveling surfaces on all sides. The main task is to remove irregularities that arise during the drying of lumber from warping. After rough processing, minor defects in the form of insufficiently high-quality planing are allowed. Next, we remove those defects that will affect the quality of the final product. We receive 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 should be cut out from the workpieces or sorted to obtain cheaper materials.
- Thus, laminated laminated wood for painting may contain more defects than high-quality laminated veneer lumber or board:
- blue;
- knots;
- resinousness;
- presence of wane;
other types of damage.
Trimming of lamellas occurs in automatic or semi-automatic mode. The automatic mode involves cutting parts according to a given program. When working in semi-automatic mode, the machine operator’s task is to determine which pocket to direct this or that lamella for facing.
In order to use wood to the maximum, lamellas with defects are glued together using technology - one side of the finished product (the front) should not contain defects, and all defects should appear on the wrong side of the product. To do this, it is important not to make mistakes when arranging the material to be spliced. Do the same if there is wane. The lamellas are laid so that all the parts with the wane are on one of the ends of the finished product.
The workshop must have a specially designated storage area for each type of lamella.
All received lamellas are stacked by grade on pallets and signed. This approach allows you to clearly monitor the production process. The splicing of the lamellas is carried out only after the accumulation of volumes sufficient for the work of the shift. In other cases, this is irrational, since it requires a lot of unnecessary operations to rearrange equipment and raw materials.
In the production of laminated veneer lumber, losses inevitably occur when cutting tenons for joining and when cutting spliced lamellas to the finished size. It is much more profitable to produce products of longer length, since this significantly reduces the amount of waste. On the website Stankoff.RU you can buy equipment for wood joining from leading manufacturers. In stock and on order, more than 77 models of machines for joining wood along the length of best prices . Only profitable offers from and photo. Check prices with managers.
Application and features of the technological process
The use of technology for combining processed short-length blanks in the production of lumber with specified parameters can significantly increase the profitability of woodworking production. Industrial equipment used for wood joining in a complex process of creating quality products, not inferior in strength to solid wood elements.
The machines are designed to connect individual parts wood into a monolithic piece with no visible seams. Modern technologies splices allow you to achieve complete illusion whole solid wood and guarantee 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. Leveling lumber.
- Trimming work using milling to form butt joints of the required configuration.
- The process of joining bars, including laying, gluing and pressing the material until the adhesive composition is completely polymerized.
After each stage, parts are sorted in accordance with the standards of the technical specifications. Upon completion, surface finishing and packaging of the finished product are performed. From the lamella obtained on a machine for splicing short parts along the length, molded products, lining, floorboard, elements of entrance and window groups. The installations allow you to adjust operating parameters with extreme precision and create finished products with uniform texture and surface color.
The operating principle 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 include working units:
- for loading workpieces;
- cutting tenons;
- applying adhesive composition;
- moving parts to the press;
- pressing module.
Machines that receive parts after processing in auxiliary installations load material with preliminary joining of parts, and alternately transfer the workpiece to the gluing and crimping device. Adjustment of the length of the spliced lamellas and the force when compressing the elements is carried out by special mechanisms. The highest productivity in work is shown by two-channel models, which allow simultaneous selection and pressing of workpieces on different working lines.
Interstate standards define General requirements to adhesive joints of a gear nature, according to which, when operating a machine for splicing wood, specific end pressure standards must be observed. Depending on the load on the wooden elements during operation, wood splicing is performed using different ways allowing parts to withstand longitudinal or transverse compression:
- oblique cutting along the ends;
- more durable connection using the “oblique mustache” technology;
- straight overlay with fastening.
Formed in the process pre-treatment wood waste used for the manufacture of pressed products. The equipment is characterized by an extremely low percentage of defects, which becomes possible only as a result of incorrectly adjusted press pressure or insufficient thickness of the applied glue. Correct machine settings ensure extremely accurate geometric shapes of products and impeccable cleanliness of the smooth surface.