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Problems that must be paid attention to in CNC machining of molds

    1 .Precautions for copper processing

    ①The order of the tool path for copper male processing:
    Roughing of the grooving tool path of the flat knife surface (or roughing of the milling tool path of the flat knife)  
    –Surface smooth cutter on the surface of the ball cutter parallel milling cutter
    –Ball knife contour profile tool path side light knife
    –Flat cutter profile milling cutter path calibration datum surface smooth cutter.
    ②The machining allowance is 0.2-0.5 when roughing.
    When the light knife is used, the tolerance is 0.005—0.02,
    The step distance is 0.05—0.3,
    The machining allowance is -0.1MM-0.3MM

    2.Precautions for front mold processing

    ①Tool path sequence: rough surface grooving tool path for large knife, rough knife path for small knife contour, large knife (ball knife) parallel milling tool path light knife, small knife parallel milling tool path light knife. When the front mold is manufactured, there is generally a matching copper male, which is mainly based on rough tool paths, supplemented by local curved light tools.
    ②With the parting surface and the pillow surface, it is necessary to add time together, the parting surface pillow surface is processed in place, leaving no allowance, and the cavity part is left with a margin of 0.2—-0.5, so as to make sparks. If there is only a young male, leave a margin of 0.3. Thick and young males are sometimes available, and a margin of 0.5 can be left. A margin of 0.1 can be reserved for the touch-through position and the wipe-through position of the front mold, which is used for the front and rear molds to match the molds.
    ③Use a large-diameter round nose knife (knife handle) when opening rough, as the knife diameter is too small, it is easy to break the knife and bounce the knife. It is also used as much as possible when the knife is in the middle.
    ④The toolpath range in surface machining is calculated based on the movement path of the tool center axis, that is, the actual processing area is larger than one side of the selected toolpath range limit frame by a tool radius value, and the toolpath range limit frame parameters should be set reasonably. Avoid processing beyond the actual processing needs.
    ⑤ The material of the front mold is hard, and it should be checked carefully before processing to reduce errors and cannot be easily welded!(CNC ALUMINUM CHASSIS)

    3.Precautions after Modulo Plus

    ①The order of the back mold tool path: rough surface grooving tool path for large knife, rough surface grooving and roughening for small knife limit range, clear angle, large knife (ball knife) parallel milling cutter path smooth, small knife (ball knife) parallel milling tool path limit Scope clear angle, light knife, flat knife and other high profile tool path clear angle.
    ②The material of the back mold is the same as that of the front mold, and the round nose knife (knife handle) is used as far as possible.

    4.CNC machining precautions

    A. Mould and product fit tolerance
    ①The matching positioning of the upper and lower shells is guaranteed by the lip, and the tolerance of the concave lip and the convex lip is generally 0.1 per side.
    ② Usually the accessories (such as transparent mirrors) on the big body of the shell are 0.1-0.2 smaller than the size of the big body on one side.
    ③The shape of the movable accessories (such as buttons) on the big body is 0.1-0.5 smaller than the shape of the big body.
    ④If the surface shape of the accessories is the same as that of the big body, it can be trimmed from the corresponding position on the body surface.(CUSTOM KNOB)
    B. Choice of cutting point
    When programming the tool path, the knife can be placed at any specified height and position. When the first knife is just started to process, the amount of the knife is often relatively large, which is easy to cause the knife to break and the knife to bounce. The first layer of cutting knife is empty, and the knife is cut outside the material as much as possible. This problem must be paid attention to.
    C. Knives, Knives, Knives
    Such phenomena often occur when the tool feed is large, the tool clamping length is too long, and the tool diameter is small.
    When the corner radius and the tool radius are the same, it is easy to have inaccurate external dimensions, which is called stealing the knife —— you can use a knife with a smaller diameter to clear the corner in layers, and then change the larger knife to solve the problem. When the depth is low and large, it can be processed in layers.
    D. gouge check
    Excessive cutting is a frequent problem, which should be paid special attention to. The solution is to simulate the tool path and check it repeatedly at various azimuth angles. The tool path that is not checked is not allowed to be machined. During profile milling, improper selection of the cutting point will cause overcut, which can be avoided by changing the cutting point.
    E. The content of the computer gong processing order
    In order to facilitate communication with the operator, the processing sheet (program paper) should include:
    ①NC program name
    ②Tool type
    ③Tool diameter
    ④Tool clamping length
    ⑤ Machining allowance
    ⑥Tool path type (roughing or smooth knife)
    ⑦Original graphic file name (eg cnc1c:mc9acb01s.mc9)
    ⑧If there are special processing requirements, a brief description should be attached
    F. Tool clamping length
    Refers to the length of the tool that is left outside the tool chuck after being clamped by the chuck. It should be installed as short as possible to improve rigidity under the condition of ensuring no collision.

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