The basic choices are to either fill, sand and buff the affected area or find a way to mask the defect so that it won’t show on your completed model. 4. 7. Selçuk GEDİK Mechanical Engineer . How to Eliminate Ejector Pin Marks in Injection Molding. All the above causes create unnecessary internal stress for the molding of products, so we need to reduce the ejection resistance and stress being applied by the ejector pins on the plastic parts. Sprue lock pin: When mold opening, runner will stick in sprue lock pin. They apply a force to eject a part from the mold, and in some cases can leave marks. If you’re not lucky and the pin is fairly small in diameter, the pin will usually buckle and break within the ejector housing. Ejector pins are the "bouncers" of the plastic injection molding world. Plastic Mould Ejection.

Thanks. Ejector pins marks in DFM Report At Plastopia, ejector pin marks are showed on our DFM report, and you will need to confirm them before tooling. 5.

There are two ejector plates in the injection molding. Download : Download full-size image; Fig. If parts with accurate dimensions are needed, allowances must be made for this shrinkage when establishing the dimensions of the cavities.
This distance use to assemble ejector system. In Ideal Group, our goal is to design and position pins to minimize their effect on your parts, and while Ideal Group typically determines pin placement, customers get to sign off on pin locations before an order is finalized. » injection molding » 5 Ejection Methods For Plastic Mold.

Spacer block: It will create distance between bottom plate and core plate. Ejector Pins Location in injection molding Ejector Pins Location in injection molding Selchuk (Automotive) (OP) 24 Dec 15 14:31. RE: Ejector Pins Location in injection molding BrianPetersen (Mechanical) 24 Dec 15 14:42. When molding an Injection Mold, there is a problem that often plagues the producer, that is, the injection molded part will have the ejector stress mark.Generally, there are two kinds of phenomena, one is slightly mark, that is, under the fluorescent lamp, the product and the human eye can only be seen at an angle of 45 degrees. Causes: Flash can occur when the mold is not clamped together with enough … Ejector pins are the “bouncers” of the injection molding world. Reduce injection rate, optimize the design of the feed system and realize a sound mold filling. Image From Paulsontraining.com . Consequently, a ghost mark could easily be formed on the part surface. This will allow the ejector plates to fully extend and retract—leaving a portion of the broken pin protruding … Ejector pins marks in molded parts Below are examples of the marks in actual molded samples. Using Ejector Pins Properly on Molded Parts Why the proper design and position of ejector pins can minimize their effect on your parts Ejector pins are the "bouncers" of the injection molding world.
8. 6. This extrusion cools and remains attached to the finished product. Avoid excessive injection of melt. Ten injection molding defects and how to fix them (flow lines, sink marks, voids, delamination, weld lines, short shot, and more). Typical routes for escape are through the parting line or ejector pin locations. They apply a force to eject a part from the mold, and in some cases can leave marks. Ejector plate: Use to assemble ejector pin, return pin, ejector stopper. Ok, so you decide you want to get rid of the ejector pin marks and/or sink marks. The causes thereof comprise: Ejector pin marks usually refer to the glossy or white imprints on the surface of a injection molded product, as well as the different levels of glossiness – dark or shadow, without convex or concave – visible directly opposite to the ejector pin location. Filling. Reduce injection pressure and dwell pressure. Shorten dwell time.

ejector marks injection molding Cause of ejector mark.