Recommendations for Cutting and Handling Melamine Boards

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1 Recommendations for Cutting and Handling Melamine Boards The three main factors of this process which should be taken into account in order to achieve a well finished cut are: the machine, the cutting tool and the operator. In the event of a problem during the cutting process, the following guide of possible scenarios may help the operator or the person in charge of production to determine which of them is more unlikely or likely to produce the observed failure. MACHINE: Vertical or horizontal cutting position; Manual or automatic machine; Design defects; Condition of guide rails and bearings; Selection of the spindle rpm; Feeding speed of carriage, saw blade and scoring saw blade; Vibrations of the spindle, motor and transmission set; Error in the square and panel incorrect support; Misaligned saw and out-of-square issues; Defective or very small pressure plates; Height regulation of the main saw blade and the scoring saw blade; Condition of fasteners in automatic machines. MAIN SAW BLADE AND SCORING SAW BLADE SET: Inadequate or defective profile; Scoring saw blade suitable for the machine; Quality of cutting inserts; Thickness and quality of bodies; Dynamic balancing and flatness of bodies; Proper sharpening of inserts; Geometry; Relation between the cut widths of both blades; Shaft speed and feeding speed; Proper face, back, tangential and radial angles; Gullet and chip discharge. OPERATOR Training in the operation of the machine; Training in the height regulation of the main saw blade and the scoring saw blade; Assembly of main saw blade and the scoring saw blade; Recognition of cut defects; Cleaning of the machine and the workplace. General Recommendations The use of saw blades with teeth tipped with tungsten carbide (widia) or diamond inserts is recommended, by means of which a higher cutting quality is achieved, though it is more expensive. Cutting saw blades should have a minimum of 60 teeth and these should be at least 2,2mm thick. It is recommended that saws be cleaned on a regular basis, especially the teeth sides and their supporting structure. Generally, after a period of use, a dark brown coating develops. The reason for this is the wrong selection of cutting speed and/or feeding speed of the main saw blade and the scoring saw blade; when speed is higher than recommended, the saw blades generate high temperature and burn at the cutting

2 area. This coating thickens the tooth and widens it more than what it can cut with its edge, resulting in chipping and aesthetically undesirable unclean cuts. Avoid using saw blades whose center bores do not correspond to the arbor diameter of your equipment. In these cases, some users attempt to make up an adaptor. DON T DO THIS! This is counterproductive because it generates vibrations and clamp nuts can become loose, which may even turn your machine into an unsafe tool to use. Tool sharpening should be performed by a professional who should also have automatic machines. Manual tooth sharpening is not recommended since very accurate angles and geometric parameters must be observed, as shown in the following illustration: The most suitable profile for cutting melamine in a saw is the trapezoidal-flat one. This is the most resistant profile and it splits the chip into three parts during the cutting process, involving less effort than the other profiles. As regards the scoring saw blade, we can find the cone-shaped profile or the flat profile. In the foregoing illustration, we can see the designs. Cutting machines generally characterize by having high-revolution motors. This means that arbors and rotating parts should be well balanced in order to avoid any vibration that would spoil the cut or would cause melamine to splinter. Carry out a thorough inspection and maintenance of your cutting machines and equipment on a regular basis. Check that the main saw blade is perfectly aligned with the scoring saw blade. They must work at the same cutting plane. Teeth of the main saw blade and the scoring saw blade must have the same width or thickness.

3 Verify the levels of the fixed cutting table and the sliding table. They must be at the same level. Make sure that the board is well supported at the cutting area. Insufficient support causes vibration during the cutting process. Check that the guide rails of the sliding table are in good condition and that the table slides easily. Check the parallelism between the direction in which the sliding carriage moves and the plane of the cutting saw blade. Make sure that the equipment is firmly fastened to the floor. Recommended cutting tools: Main saw blade Scoring saw blade Tooth geometry Trapezoidal-Flat (alternate) Flat Number of teeth 96 mm 24 mm Tooth pitch 9.82 mm mm Tooth width 3.2 mm 3.2 mm Thickness 2.2 mm 2.5 mm Inside diameter 30 mm 20 mm Outside diameter 300 mm 150 mm Max RPM 7,600 15,200 Cutting Speeds For melamine cuts, peripheral speeds between 60 and 80 m/s are recommended. The following table shows how to obtain the rpm at which the saw should run, on the basis of the diameter of each saw blade and different cutting speeds at the periphery (at the teeth). CUTTING SPEED (r.p.m.) SAW BLADE DIAMETER 60 m/s 70 m/s 80 m/s 90 m/s 100 mm mm mm mm mm mm mm mm mm mm mm mm

4 Feeding Speed It is important to be well aware that the feeding speed of the saw and scoring saw carriage, along with the rpm of the cutting tools, has a direct impact on the cutting quality. A feed rate that is too slow will build up heat in the cut causing the saw blade to burn the material, leading to a dark color and even smoke on the cut surface. Extremely fast speed will result in material breakage. Once rpm have been selected in accordance with the saw blade diameter, it is advisable to set the feeding speed at the point where the cut surface is clean or keeps the same color of natural wood without any roughness or irregularities. Feeding speed should also be constant, that is, without variation during the cutting process. Therefore, it is important to monitor the lubrication of the guide bar, bearings, chain tension, etc. CONSERVATION OF CUT PIECES Store and preserve cut pieces from humidity and adverse climatic conditions. Keep them far from doors and gates. Edges are the weakest parts in all boards with respect to collisions and humidity activity. Therefore, if the cut piece will be stored for more than 3 or 4 days, it is advisable to store it after the edge-banding has been applied. PACKAGE STORAGE AND MAINTENANCE Store and preserve cut pieces from humidity and adverse climatic conditions. Keep them far from doors and gates. Keep the product origin identification. Observe package storage and maintenance conditions. Observe the alignment of the supporting blocks provided by Sadepan in the packaging. For laminated and non-laminated materials being 10 mm thick, 4 supporting blocks per package are placed under each pallet at the warehouse. The maximum height of each stack must not exceed 6 (six) packages. For laminated and non-laminated materials being 12 to 25 mm thick, 3 supporting blocks per package are placed under each pallet at the warehouse. The maximum height of each stack must not exceed 9 (nine) packages. Alignment is important so that the weight of packages is always distributed among the position lines of the supporting blocks, thus preventing bending stresses which would lead to panel warping. The following diagram represents an alignment model for the supporting blocks of a pallet.

5 TRANSPORT Transport of boards should be carried out using stacks fastened with metal bands, in order to prevent panels from sliding and rubbing between them. MANUAL TRANSPORT It is recommended that the transport of a single board unit be carried out by two persons, preferably in vertical position. If you wish to transport a greater number of boards, a trolley should be used. In order to avoid surface and edge damage when moving boards, these should be perfectly aligned.