Avoiding Common Cosmetic Defects in Molded Parts
网页2023年12月8日 · Injection-molded part aesthetics start with draft. Sufficient draft is an important part of any mold design, even with quick-turn tooling. Vertical walls, meaning those part surfaces parallel to the direction of mold operation, should have a minimum draft angle of a 1 / 2 degree, though 2 degrees is even better. Heavily textured surfaces may ...
Eliminate Surface Defects on Molded Parts | Plastics Technology
网页2005年7月1日 · Eliminate Surface Defects on Molded Parts. Visible defects on the surface of a molded part appear as dull, glossy, or hazy areas, or as a rippled surface, called orange peel. Dull halos around the sprue and downstream of sharp edges occur when initial injection speed is too high, which causes displacement of cooled surface material.
How to Get Rid of Bubbles in Injection Molding
网页2015年3月31日 · Instead, use a heat gun or something similar. Then as you gently warm the area of the part where the bubble is, the bubble should change form. If it is a gas bubble, the gas will warm up and expand, raising the surface, and often will …
Get Better at Quoting Injection Molded Parts: Part 3
网页2021年1月20日 · Get Better at Quoting Injection Molded Parts: Part 3. Follow these detailed tips to get the jobs you want. This installment focuses on the mold and the molding machine. Parts one and two of this series focused primarily on the raw-material portion of a molded part’s cost. This month, I’ll discuss the mold and molding machine’s portion.
Injection Molding | Plastics Technology
网页3 天之前 · Lab System Targets Large Part, Process Development for Combo Injection Molding, PUR Coating. KraussMaffei has paired an MXW 4500 injection molding machine featuring more than 5,000 tons of clamp force with two RimStar polyurethane (PUR) metering systems and three different mixing heads in a new ColorForm lab line at its …
Are Your Sprue or Parts Sticking? Here Are Some Solutions
网页2014年7月28日 · Here’s my list: 1. Scratches can cause material sticking in the sprue, part sticking on the “A” side of the mold upon mold opening, or part sticking to the “B” side of the mold at part ejection. Again, scratches must be polished out, and polishing must be done in the direction of draw or mold opening. 2.
Dimensional Stability After Molding: Part 4 | Plastics Technology
网页2013年3月25日 · Dimensional Stability After Molding: Part 4. In the first three parts of this series we focused on those influences that cause molded parts to get smaller. But there are environmental factors that also cause parts to increase in size over time. Engineering Resins. Know-How.
Understanding the Effect of Pressure Losses on Injection Molded …
网页2024年3月7日 · Due to the application of the pressure, compression of the sponge occurs while the amount of pressure transmitted down the length of the sponge decreases. From 15,000 psi in front of the screw during packing to 9,000 psi at the gate and 7,000 psi at the end of fill, pressure is lost throughout the molding process. Source: Umberto Catignani.
Get Better at Quoting Injection Molded Parts: Part 1
网页2020年11月20日 · Get Better at Quoting Injection Molded Parts: Part 1. Follow these detailed tips to get you the jobs you want. This installment focuses on the various raw material aspects of quoting. You may not think that quoting injection-molded parts is a relevant subject for the Tooling Know-How column of this magazine.
Secrets of Successful Thin-Wall Molding | Plastics Technology
网页2010年6月1日 · Molds: make 'em rugged. Speed is one of the key attributes of successful thin-wall molding. Faster filling and higher pressures are required to drive molten thermoplastic material into thinner cavities at a sufficient rate to prevent freeze off. If a standard part is filled in 2 sec, then a reduction in thickness of 25% potentially can require ...