Category: Injection Molding

Zero-draft walls are technically possible. They also guarantee ejection problems, surface damage, and production headaches that dwarf the appearance benefit of perfectly vertical walls. Draft is the slight angle added…

Runners, sprues, and rejected parts contain the same material that went into good parts. Throwing them away throws away profit. Yet regrind management is surprisingly neglected in many operations, treated…

A customer approves a color sample, then rejects the first production run because it “doesn’t look the same.” The color is within specification. The problem is perception, lighting, texture, and…

The mold determines part quality, cycle time, maintenance costs, and flexibility for the next decade of production. Buying a mold without understanding these tradeoffs is buying problems you haven’t imagined…

Adding material to make a part stronger often makes it weaker. Thick sections cool slowly, creating internal stresses and voids that compromise both strength and appearance. This counterintuitive reality drives…

Undercuts are features that prevent a part from releasing in the direction of mold opening. Every undercut requires a mechanical solution, and every solution adds cost, complexity, and potential failure…

A 32-cavity mold produces parts faster, but if it takes eight years to recoup the additional investment, that speed is a liability, not an asset. Cavitation decisions balance tooling investment…

Machine tonnage is the spec everyone asks about first. It’s also the one most often misunderstood, over-specified, or mismatched to actual requirements. Tonnage refers to clamping force, not machine size…

Electric machines promise energy savings, precision, and cleanliness. Hydraulic machines offer power density and lower capital cost. The choice depends on what you’re making and what you’re paying for electricity….

A 3,000-ton injection molding machine weighs more than a commercial airliner. Operating one requires specialized infrastructure, trained personnel, and applications that justify the investment. Large tonnage molding represents a distinct…

A plastic pellet enters a machine at room temperature. Ninety seconds later, it emerges as a finished part with tolerances measured in thousandths of an inch. This transformation happens through…

Over 20,000 thermoplastic grades exist on the market. Selecting the right one requires filtering through this complexity to find the handful that actually fit your requirements. Most selection failures occur…

Post-consumer recycled content sounds like a straightforward sustainability win. Then you discover the contamination, the variability, and the property compromises that make it genuinely complicated. Recycled plastic isn’t simply virgin…

Polypropylene’s living hinge can flex a million times without breaking. This single property created entire product categories, from flip-top caps to storage containers. But living hinges represent just one aspect…

Two pressure settings control the entire fill and pack sequence. Set them wrong, and you’ll either short-shot the part or over-pack it into stress fractures. These settings interact in ways…

The gate is the smallest feature in the mold. It’s also where most quality problems originate. This narrow channel controls how material enters the cavity, how long pack pressure can…

The mold surface temperature varies by 15°C between the gate area and the far corner. That gradient doesn’t show up in the process printout, but it shows up in every…

Select a 200-ton machine for a part that needs 250 tons of clamping force, and you won’t just get flash. You’ll damage the mold, stress the machine, and produce scrap…

Shaving two seconds off a cycle time sounds trivial until you calculate the annual impact: on a 24/7 operation running 30-second cycles, that’s over 75,000 additional parts per year from…