The scratche (scrape marks) on the appearance of an injection molded product usually occur on such deep-cavity products as chargers, routers, and chassis, etc. It is also a particularly common problem during the injection molding process, known as one of the 10 most challenging problems in the mold and injection molding industry. Glossy products, as well as products with textured sides are easily scratched. What on earth has caused it? When it comes to the scratches on the textured surface, the first thing that comes to the mind of an engineer is that the draft angle on the side of the product is not large enough, but why the scratch still exist after the draft angle is increased? So, solving the occurrence of scratches is not just a matter of the draft angle. In fact, it is not so simple at all. Now, let’s thoroughly analyze and solve the problem of surface scratches.   The causes of surface scratches mainly include the following factors:   I. Draft Angle   The ke...

The definition of weld lines: When multiple plastic flow fronts meet in the cavity after encountering inserts, holes, or areas with inconsistent flow rates or interrupted melt flows, or in the case of gate injection filling, the inability of two or more flow fronts to fully “knit” together will cause the linear weld marks. The appearance of weld lines greatly reduces the mechanical strength of the product. The solution to the weld lines is basically the same as the method for reducing product sink marks.   I. Equipment To respond to poor plasticization and uneven melt temperature, the molding cycle can be extended to make plasticization more complete, and select the molding machine with a higher plasticizing capacity when necessary.     II. Mold (1) When the mold temperature is too low, raise the mold temperature appropriately or purposefully raise the local temperature at the weld seam.   (2) When the runner is too small, narrow or shallow, and the cold...

Flash, also known as flashing or burrs, mostly occurs between the matching parts of a mold, such as the parting surface of the mold, the sliding part of the slider, the clearance of the insert, and the gap of the ejector, etc. If the flashing is not resolved in a timely manner, it will be further worsened, so that the mold will be pressed to cause local collapses or other permanent damages. The flashing occurring in the clearance of the insert and the gap of the ejector will also cause the product to stick on the mold, thus affecting ejection.   Flash is actually the excessive plastic material which enters the matching gaps of the mold and is attached to the final product after cooling. It is very easy to solve the problem of flashing, i.e., keeping the melt out of the matching gaps in a mold. The plastic melt usually enters the mold matching gaps in two scenarios: one is that the mold matching gap is large, making it easy for the melt to get in; the other is that the mold matchin...

  The shrinkage rates of different plastic materials are different. Usually, the raw materials that are prone to sink marks are crystalline, such as nylon. During the injection molding process, the crystalline plastic is heated to a fluid state, with the molecules randomly arranged; when filled into the cold cavity, the plastic molecules are slowly arranged neatly to crystallize. As a result, the volume is shrunk to be smaller than the specified dimensional range, which is referred to as the “sink mark”.   The shrinkage rates of various plastic materials(mold shrinkage rate) are shown below:   Injection processing: Regarding control of the injection technology, the causes of sink marks include: insufficient pressure, excessively slow injection speed, small gate or long runner. Therefore, when using the injection molding machine, it is necessary to pay attention to the molding conditions and whether the holding pressure is enough to prevent the appearance of s...

    Plastic Injection Mold Steel Selection for Molding Components   Molding components refer to the mold parts or components which have a direct contact with the plastic materials to form a product, such as mold cavities, mold cores, sliders, inserts and lifters, etc.   The steel quality of the molding components has a direct influence on mold quality and service life, and determines the appearance and quality of a plastic injection molded product, so plastic injection mold making factory must make careful selection. Generally speaking, materials have to be selected based on contract stipulations, client requests, as well as product / mold requirements and characteristics.   Principle for steel selection of molding components: different types of steels need to be selected based on types of plastic, product shapes / dimensions, product appearance / quality / application requirements and production scale, etc., while paying attention to the various material perfo...

2024 Trends for the CNC Manufacturing Industry The landscape of the CNC (Computer Numerical Control) manufacturing industry is ever-evolving, with advancements in technology and shifts in consumer needs shaping the trends that define the sector. As we journey through 2024, several key trends are emerging that are set to redefine the industry. Let’s delve into these transformative factors shaping the CNC manufacturing industry.   Automation & Robotics In 2024, CNC manufacturing continues to leverage the power of automation and robotics. Automating repetitive tasks boosts efficiency and accuracy while freeing up human operators to focus on more complex tasks. Robotics, integrated with CNC systems, are increasingly used for tasks such as loading and unloading parts, leading to increased production rates and reduced labor costs.   Industrial Internet of Things IIoT is rapidly transforming CNC manufacturing, offering capabilities for machines to communicate with each oth...