The basis for the selection of woodworking milling cutters and the requirements for the use of woodworking cutters

       1. The properties of the material being cut

The objects of wood cutting are solid wood and wood composite materials. Solid wood can be divided into soft wood, hard wood and modified wood, etc.; wood composite materials include plywood, laminated veneer, pattern board, directional pattern board, large pattern board, gypsum pattern board, cement Particleboard, hardboard, medium density fiberboard, high density fiberboard, blockboard, laminated lumber, etc. Some wood or wood composite workpieces are also veneered on one or both sides.

Wood is a natural polymer material composed of wood fibers arranged in a certain way. One of the most significant properties of wood is anisotropy. Therefore, there are vertical, horizontal, end and transitional cutting in solid wood cutting. .

Wood composite material is a composite material of wood monomer, such as veneer, shavings or fiber, etc., which is compounded by an adhesive under a certain temperature and pressure. Its properties are determined by the wood monomer, arrangement and the properties of the adhesive. Depends. Machining properties also vary due to their structure and the proportions and properties of additives. For example, MDF is close to isotropy, and the cutting resistance is almost the same everywhere on a sheet; due to the uneven pavement density of particleboard, the difference between the surface and internal structure of the sheet, the cutting resistance varies greatly; blockboard is made of The solid wood slats are glued together, and there are differences in the grain direction between the slats, so the cutting process shows the same and different properties as the solid wood.

2. Cutting direction

When cutting solid wood, according to the direction of the blade relative to the wood fiber, wood cutting is divided into longitudinal, transverse, end and longitudinal end, longitudinal and transverse and transverse end cutting.

3. Tool rotation direction and feed direction

According to the rotation direction of the machine tool axis and the direction of the wood workpiece feed, determine the inclination direction of the blade on the tool

4. Tool and workpiece stability

The stability of the tool and the workpiece in the cutting process includes several aspects. The stability of the workpiece refers to the smooth feeding of the wood workpiece without jumping during the cutting process. The measures taken to strengthen the stability of the workpiece mainly include reducing the center of gravity of the workpiece and increasing the contact area. Therefore, for the vertically installed forming milling cutter, the installation form of the large-diameter milling cutter on the top is beneficial to improve the stability of the workpiece processing, but the stability of the tool is reduced at this time. To improve tool stability, in addition to requiring the tool to have a good dynamic balance, it also requires that the structure, installation size and quality of the tool meet the requirements of the stability standard. For example, the rotation frequency of the tool should be separated from the natural frequency of the tool by a certain value. The size of the cantilever installation is limited.

5. Processed surface quality requirements

The surface quality of wood workpieces includes surface roughness, geometric dimensions and shape position accuracy. The quality of the milling surface is related to the geometric parameters and shape position accuracy of the milling cutter, the assembly accuracy of the milling cutter, the stability of the milling cutter, the motion accuracy and vibration of the machine tool, and the corrugation height of the milling cutter surface is related to the feed per tooth of the milling cutter. Therefore, reducing the feed rate, increasing the rotational speed, increasing the number of cutter teeth, and increasing the diameter of the milling cutter can reduce the height of the milling surface ripple and improve the surface quality.

Requirements for the use of woodworking knives

Improper use of woodworking knives in on-site production can easily lead to defective parts. We should pay attention to the following aspects in specific operations.

(1) Woodworking knives with imperfections shall not be used.

(2) When installing the knife, pay attention to clean the dust of the gasket to prevent the knife from being installed inclined. For machines with feeding wheels, crawler belts, and rollers, pay attention to whether there is any foreign matter on them during operation.

(3) For planing machines, note that the edge of each blade is installed on the same cutting circle, and the blade edge is exposed within 3mm of the platform.

(4) Since the tools are usually produced by the tool supplier according to the drawings provided by the furniture manufacturer, the shape of the processed parts should be strictly based on the data or large drawings. If the difference is found to be caused by processing factors, it is necessary to consider whether the tool itself is defective, such as tool aging and defects, and the size of the new tool does not match. Old knives can be replaced, while new knives can be ground.

(5) Unfavorable woodworking tools during processing may easily cause undesirable phenomena such as tool jumping, fluffing, and blackening of components, and should be replaced in time.

(6) According to the processing properties of different parts, there are some differences in the use requirements of tools.

Woodworking milling cutters: processing must pay attention, because the speed is not as fast as the six sides; the processing speed can not be too fast, especially in the arc.

①Flexible use of positive and negative knives to shape from high to low grain direction to prevent material from cracking.

② When processing the plate, the tool is easy to passivate, causing the parts to jump and turn black, and the tool needs to be changed frequently; solid wood can slightly prolong the use time of the tool.

③ For double-axis straight knives, if the front and back are used interchangeably, the grinding time can be saved and the knives can be protected.

④The selection of tools for splicing after splicing must meet the standards. Need to recalibrate after sharpening, or compare samples after tool change.

⑤In the process of processing, the edge of the thin-skinned material is broken and the tool needs to be changed.

⑥ For the processing of groove and birch structure, the tool can be used for a little longer.