KNOW HOW - INJECTION MOLDING

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The Importance of Gauging Residence-Time Distribution—Part 2

Each molecule in the molded product can have a different residence time. This variance is reflected in the Residence-Time Distribution, which you can learn how to determine below.  
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In this Tech Day session, experts Walter Smith of Nordson and Steve DeAngelis of Davis-Standard will speak about new developments in high-speed sheet extrusion and next-generation tooling.

Residence Time and Residence-Time Distribution—Part 1 of 2

Failing to calculate and accurately account for residence time can compromise material integrity before it’s even injected.
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Injection Molding: Understand the Link Between Feed Throat Temperature & Bridging

Save time and money by properly controlling the feed-throat temperature. In some cases—but not all—it can help you solve a bridging problem.
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How to Know When Your Process is Ready to Make Acceptable Parts

Focus on six key metrics to help you determine when a process is lined out and stable enough to start production. 
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Back to the (Re)Grind

Some amount of scrap—generated in startup, shutdown or defective parts—is inevitable. How can you reclaim regrind into new profitable parts?
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Fundamentals of Proper Press Shutdown

Press shutdown procedures have a significant impact on achieving smooth machine startups and restarts to improve uptime. Here’s a procedure you might want to deploy in your molding operation.
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The Cosmetic Process Window: Key to a No-Tweak, Robust Process

Establishing a process with the widest possible cosmetic window can help put your injection molding on cruise control.
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Don’t Get Caught in the Flash-and-Shorts Chase

Injection molding’s most common defects can have inverse correlation, where correcting one causes the other, leading to the “chase.”

Follow These Tips to Sanitize Machine Controller Screens & Buttons

Keeping your workers safe from the coronavirus makes it extremely important to institute a sanitizing procedure on all touch surfaces of the controller, screen and operating panel. I did some research and here’s what I found.

In Search of a Universal Setup Sheet

Duplicating a process from one injection machine to another is frustrating and time-consuming. Develop a mold-specific setup sheet that works in all kinds of presses by differentiating plastic parameters from machine parameters and duplicating those plastic conditions from machine to machine, electric or hydraulic. 

Revisiting Shot Size vs. Barrel Capacity

We’ve covered this topic before, but it’s important enough to warrant another look..
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How Can Molders Achieve Effective Process Monitoring?

You have developed a proper process; now you need to monitor that process to ensure its stability through a run.
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V-to-P Ramp Time and Over-Travel

Many injection machines use ramp time to control the transition from injection pressure to hold pressure and reduce over-travel. Do you know how to set yours?
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Graphing Injection Pressure: What Should Pack & Hold Curves Show?

Are you sure your press is doing what you want? Visit your controller often to ensure your machines plot the pressure vs. time graph for all your processes. Here let’s focus on pack and hold.

Understanding—and Using—Decompression to Your Advantage

Decompression—aka suckback—is a very important setting on an injection molding machine. On today’s machines, molders typically get the option to set decompression before and after screw rotation/recovery. Are they using this feature to their advantage?

How to Deal With Residual Stress in Molded Parts

Here are design, molding, and fixturing considerations to help you handle this unavoidable issue.

How to Manage Pressure Loss in Injection Molding

Achieving a process window wide enough to ensure consistent part quality depends on achieving sufficient pressure at end of fill.
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How to Quickly Verify Your Machine & Process Setpoints

For a quick check of your process setup, the injection-pressure-vs.-time graph is your best tool.
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The 'Butterfly Effect' in Injection Molding—A Connected Process

In injection molding, a seemingly minor change in a setpoint can have a significant impact on part quality and process robustness and repeatability. That’s why Scientific Molding focuses on process outputs, not setpoints.
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Mold-Clamping Details for Profit

Taking time to sweat the details of clamping is not much fun, but they do make a difference in a company’s bottom line.

What’s With All the Static?

Static buildup on polymers can cause a variety of problems, some rather unpleasant. Yet there’s an inexpensive way to eliminate it, and we have data as proof.

PART 2: The Importance of Consistent Fill Time

To make identical parts, you need to keep fill time constant. In part one we covered the why. Here’s the how.