I had him repeat that to me again to make sure I had understood his theory: “As it runs, the metal in the drop gets pushed closer to the tips.”  My response: “How high do you think the viscosity of the material is in those drops with the tips completely blocked off with metal?” I waited a moment before answering the question myself: “Infinitely high.”

If you looked at four machines from four different suppliers, you’ll find four different sets of icons and terminologies, all in different layouts.

Ultradent's entry of its Umbrella cheek retractor took home the awards for Technical Sophistication and Achievement in Economics and Efficiency at PTXPO.

Determining whether foreign material blocking a hot-runner nozzle tip is a one-time issue or an ongoing contamination event is a key first step in dealing with the situation. (Photo: Tony Deligio)

This month’s resin pricing report includes PT’s quarterly check-in on select engineering resins, including nylon 6 and 66.

Introduced by Zeiger and Spark Industries at the PTXPO, the nozzle is designed for maximum heat transfer and uniformity with a continuous taper for self cleaning.

Whenever we are discussing plastic flow—whether in the cavity steel, a cold -unner system, or through a hot-runner system—the first rule we need to remember is that plastic flows in the direction of least resistance. This is extremely important when a foreign material invades a hot-runner system. In the case above, the FM was a non-ferrous metal that was completely obstructing the hot tips on many cavities. A quick inspection of the material-handling system showed no obvious signs of an entry point for the FM; but even as the hot tips were replaced, they would almost immediately block off again. This molder continued to mold, thinking that as the job would run, the FM in those drops would be pushed towards the tips with each shot.

In this collection of articles, two of the industry’s foremost authorities on screw design — Jim Frankand and Mark Spalding — offer their sage advice on screw design...what works, what doesn’t, and what to look for when things start going wrong.

Gifted with extraordinary technical know how and an authoritative yet plain English writing style, in this collection of articles Fattori offers his insights on a variety of molding-related topics that are bound to make your days on the production floor go a little bit better.

The first rule of plastic flow—whether in the cavity, a cold-runner system, or through a hot runner—is that plastic flows in the direction of least resistance.

In addition, while there is an increasing number of material options that can be used with 3D printing, it still cannot match the choice of materials compatible with injection molding.

The aim of this presentation is to guide you through the factors and the numbers that will help you determine if a robot is a smart investment for your application. Agenda:  Why are you considering automation? What problems are you trying to solve? How and why automation can help Crunch the numbers and determine the ROI

Multiple speakers at Molding 2023 will address the ways simulation can impact material substitution decisions, process profitability and simplification of mold design.

Across the show, sustainability ruled in new materials technology, from polyolefins and engineering resins to biobased materials.

Core Technology Molding turned to Mold-Masters E-Multi auxiliary injection unit to help it win a job and dramatically change its process.

Mike Sepe has authored more than 25 ANTEC papers and more than 250 articles illustrating the importance of this interdisciplanary approach. In this collection, we present some of his best work during the years he has been contributing for Plastics Technology Magazine.

Due to the fountain flow of plastic, pressure can only be transferred cylindrically through the center of the plastic flow. This area is commonly referred to as the effective flow area. Think of it this way, if you have a cold runner cut in a rectangle that measures 10 by 20 mm, the effective flow diameter is going to be just under 10 mm. It is as simple as drawing the largest circle you can inside a cross-section of the runner.

While the melting process does not provide perfect mixing, this study shows that mixing is indeed initiated during melting.

Mold maintenance is critical, and with this collection of content we’ve bundled some of the very best advice we’ve published on repairing, maintaining, evaluating and even hanging molds on injection molding machines.

A significant drawback, however, is the fact that there are design limitations inherent in injection molding, with some geometries being difficult to remove from the mold, and precise and delicate designs being difficult and expensive to mold accurately. Also, it is difficult, costly and sometimes impossible to correct tooling mistakes or change tooling to optimize or iterate new designs. Often, new tools are required, with all this implies in terms of cost and time—tools often taking weeks if not months to fabricate.

Injection molding is still the go-to technology for high-volume plastic part production, but it is characterized by significant up-front capital investment in tooling, which is also time-consuming and difficult and expensive to adapt. The technology can use several molds at the same time, which means that it is ideally suited to the mass manufacturer of parts and components cost effectively—its cost effectiveness also promoted by the fact that there is minimal wastage as material is precisely dosed to match specific mold requirements.

Across all process types, sustainability was a big theme at NPE2024. But there was plenty to see in automation and artificial intelligence as well.

And yes, for those wondering, it is a waste of material to use non-cylindrical flow channels and a waste of time to increase the width of a tab gate in only one direction. Keeping these flow characteristics in mind, I knew any sort of protrusion of the vest cap into the gate would significantly reduce the diameter of the effective flow area, and any FM working its way through was going to cause an obstruction.

Perhaps the biggest advantage of the use of 3D printing, however, is that although per part it is slow compared with injection molding, its advantages in terms of design freedom, creation of geometric complexity, and part consolidation all stimulate innovation. These factors alone may be a spur to using 3D printing for multiple smaller batch runs rather than bowing purely to the economics of using injection molding for high-volume manufacture.

With 3D printing, ideal material conditions throughout a part are dictated by design, not by the vagaries of various production and post-production processes used.

3D printing exhibits a number of advantages when compared to legacy processes such as injection molding. The most important of these is the added flexibility 3D printing allows in design.

While prices moved up for three of the five commodity resins, there was potential for a flat trajectory for the rest of the third quarter.

Injection molding finds its sweet spot in large-batch production, where the requirement is for the manufacture of many thousands of identical products simultaneously. It is also best suited to robust designs based on one continuous form, and the process can produce products with superior smooth surface finish without the need for post-processing (which is typically needed with 3D printing parts).

Five industry pros with more than 200 years of combined molding experience provide step-by-step best practices on mounting a mold in a horizontal injection molding machine.

In this collection of content, we provide expert advice on welding from some of the leading authorities in the field, with tips on such matters as controls, as well as insights on how to solve common problems in welding.

Processors with sustainability goals or mandates have a number of ways to reach their goals. Biopolymers are among them.

3D printing is unique as a disruptive technology in one key respect, and that is having disrupted the manufacturing paradigm through the introduction of rapid prototyping some 25 to 30 years ago. It is disrupting manufacturing again.

August 29-30 in Minneapolis all things injection molding and moldmaking will be happening at the Hyatt Regency — check out who’s speaking on what topics today.

Sustainability continues to dominate new additives technology, but upping performance is also evident. Most of the new additives have been targeted to commodity resins and particularly polyolefins.

But, based on the orifice size of the hot tip, it is very likely that another chunk of FM would block off the gate shortly after it is unblocked.  This is one reason why even a one-time event that introduces FM into a hot-runner system can mimic an active event of contamination. If plastic can’t flow, neither will the FM, and it isn’t going to cut its way to the front of the line, like me at a donut shop.

These humble but essential fasteners used in injection molds are known by various names and used for a number of purposes.

In addition to the gate orifice diameter being much smaller than the diameter of the FM making its way through the hot-runner system, these particular hot tips also had a vest-cap installed in the space between the hot tip and the gate insert. Depending on the design of a vest cap, it can significantly reduce the effective plastic flow area. What do I mean when I say “effective” flow area?

Thousands of people visit our Supplier Guide every day to source equipment and materials. Get in front of them with a free company profile.

Over the last two-plus years, manufacturing has become more challenging than ever. These challenges haven’t been unique to the plastics industry; all manufacturing has been impacted as demand for many products continues to increase while there is also a decline in availability of raw goods. The increased pressure to keep jobs running in order to meet our customers’ and, ultimately, consumers’ demands during this global pandemic has forced injection molders to run under sub-optimal conditions.

Second quarter started with price hikes in PE and the four volume engineering resins, but relatively stable pricing was largely expected by the quarter’s end.

Say “manufacturing automation” and thoughts immediately go to the shop floor and specialized production equipment, robotics and material handling systems. But there is another realm of possible automation — the front office.

There will be few manufacturing enterprises that will not either have used or are flirting with the adoption of 3D printing at some level in 2021, be it as a complementary technology to existing legacy manufacturing processes, or indeed as an alternative. Many OEMs will be using desktop 3D printers for rapid prototyping, purely to get an early reasonably accurate 3D model of their product designs, but these printers are not designed for more exacting production applications, where repeatability and accuracy / tolerance attainment are vital.

Dealing with foreign material contamination of a hot runner will protect it, the mold and the molded parts from any unwanted particulates. (Photo: ThinkStock)

Join this webinar to explore the transformative benefits of retrofitting your existing injection molding machines (IMMs). Engel will guide you through upgrading your equipment to enhance monitoring, control and adaptability — all while integrating digital technologies. You'll learn about the latest trends in IMM retrofitting (including Euromap interfaces and plasticizing retrofits) and discover how to future-proof your machines for a competitive edge. With insights from industry experts, it'll walk you through the decision-making process, ensuring you make informed choices that drive your business forward. Agenda: Maximize the value of your current IMMs through strategic retrofitting Learn how to integrate digital technologies to enhance monitoring and control Explore the benefits of Euromap interfaces and plasticizing retrofits Understand how retrofitting can help meet new product demands and improve adaptability Discover how Engel can support your retrofitting needs, from free consultations to execution

I recently came across a molder struggling with a metallic foreign material (FM) contaminating the hot-runner system on a high-cavitation, multi-level mold. Of course, it happens to be one of the molder’s highest priority jobs that supplies one of its highest volume customers. During our first conversation I was told that there was no way this molder could afford to take the mold down long enough to have the hot-runner system thoroughly cleaned. Although this was a difficult situation, it did provide an opportunity to challenge everyone’s perceptions on how plastic was flowing through this hot-runner system and why the FM was taking so long to make its way through that system.

Discover how artifical intelligence is revolutionizing plastics processing. Hear from industry experts on the future impact of AI on your operations and envision a fully interconnected plant.

Despite price increase nominations going into second quarter, it appeared there was potential for generally flat pricing with the exception of a major downward correction for PP.

technotrans says climate protection, energy efficiency and customization will be key discussion topics at PTXPO as it displays its protemp flow 6 ultrasonic eco and the teco cs 90t 9.1 TCUs.

Conversely, injection molding makes design iterations costly. Beyond the high cost of upfront tooling, which as mentioned increases the more complex the part, production is restricted to the location of the production tooling. 3D printing technologies manufacture direct from 3D CAD files, so the location of manufacture is much more flexible.

Plastics Technology’s Tech Days is back! Every Tuesday in October, a series of five online presentations will be given by industry supplier around the following topics:  Injection Molding — New Technologies, Efficiencies Film Extrusion — New Technologies, Efficiencies Upstream/Downstream Operations Injection Molding — Sustainability Extrusion — Compounding Coming out of NPE2024, PT identified a variety of topics, technologies and trends that are driving and shaping the evolution of plastic products manufacturing — from recycling/recyclability and energy optimization to AI-based process control and automation implementation. PT Tech Days is designed to provide a robust, curated, accessible platform through which plastics professionals can explore these trends, have direct access to subject-matter experts and develop strategies for applying solutions in their operations.

The 3D printing machines that achieve production level repeatability and accuracy are typically costly beasts. Because of this, many potential users are put off by the large capital outlay required, and therefore approach 3D printing subcontract specialists, who not only have the levels of necessary high-quality 3D printing machines in-house but also the experience to get the most out of them.

When it comes to producing plastic parts, 3D printing is working in a space where the conventional processing technology is injection molding.

Mixed in among thought leaders from leading suppliers to injection molders and mold makers at the 2023 Molding and MoldMaking conferences will be molders and toolmakers themselves.

Learn about sustainable scrap reprocessing—this resource offers a deep dive into everything from granulator types and options, to service tips, videos and technical articles.

Join Engel in exploring the future of battery molding technology. Discover advancements in thermoplastic composites for battery housings, innovative automation solutions and the latest in large-tonnage equipment designed for e-mobility — all with a focus on cost-efficient solutions. Agenda: Learn about cutting-edge thermoplastic composites for durable, sustainable and cost-efficient battery housings Explore advanced automation concepts for efficient and scalable production See the latest large-tonnage equipment and technology innovations for e-mobility solutions

When, how, what and why to automate — leading robotics suppliers and forward-thinking moldmakers will share their insights on automating manufacturing at collocated event.

The Plastics Industry Association (PLASTICS) has released final figures for NPE2024: The Plastics Show (May 6-10; Orlando) that officially make it the largest ever NPE in several key metrics.

If plastic flows in the direction of least resistance, than nothing is happening in those drops that have been completely occluded by metal. This means that any FM in those hot-runner drops is suspended in the position it was at the time when the plastic could no longer flow through the gates. That metal isn’t going anywhere, and as soon as you open up the gate, by removing the metal or replacing the hot tip, then and only then will it move again.

3D printing requires no tooling and is agile, which facilitates quick production turnaround. With 3D printing, part cost is not connected with part complexity. As soon as complexity is introduced to an injection molded part, the requirement is for more and more expensive mold tools, which leads to an exponential increase in costs until part production is no longer viable. As 3D printing adds material, complexity of design and different incorporated shapes do not affect the amount of time that it takes to produce a part, and therefore does not lead to increased costs.

These respective sweet spots are quite discrete and play to the fact that forward-thinking manufacturers could in fact be looking at 3D printing and injection molding as complementary processes rather than competitive processes. When used constructively together, for example, pre-production cycles can be dramatically shortened before large volume production is undertaken.

In this three-part collection, veteran molder and moldmaker Jim Fattori brings to bear his 40+ years of on-the-job experience and provides molders his “from the trenches” perspective on on the why, where and how of venting injection molds. Take the trial-and-error out of the molding venting process.

While prices moved up for three of the five commodity resins, there was potential for a flat trajectory for the rest of the third quarter.

While the major correction in PP prices was finally underway, generally stable pricing was anticipated for the other four commodity resins.

Plastics Technology covers technical and business Information for Plastics Processors in Injection Molding, Extrusion, Blow Molding, Plastic Additives, Compounding, Plastic Materials, and Resin Pricing. About Us

It seems likely that moving forward, runs of perhaps 10,000 and below will soon be the domain of 3D printing, which for such volumes will render injection molding if not redundant, increasingly irrelevant when looked at through the prism of cost and time of production. However, injection molding will never be replaced, as it will typically be the technology of choice for higher volume runs.

Take a deep dive into all of the various aspects of part quoting to ensure you’ve got all the bases—as in costs—covered before preparing your customer’s quote for services.

Understanding plastic flow can help you understand how foreign materials move—or don’t move—through your hot-runner system.

If plastic can’t flow, neither will the FM, and it isn’t going to cut its way to the front of the line, like me at a donut shop.

Exhibitors and presenters at the plastics show emphasized 3D printing as a complement and aid to more traditional production processes.

Formnext Chicago is an industrial additive manufacturing expo taking place April 8-10, 2025 at McCormick Place in Chicago, Illinois. Formnext Chicago is the second in a series of Formnext events in the U.S. being produced by Mesago Messe Frankfurt, AMT – The Association For Manufacturing Technology, and Gardner Business Media (our publisher).

Also, as 3D printing is a digital process, it can be stopped post-part build or post-run and started again without punitive cost. Production volumes can be exactly aligned with demand day to day, week to week, month to month. With injection molding, once the production process is initiated, it needs to fulfill the full run immediately to remain economic, which therefore necessitates the need for warehousing—which increases the cost per part.

After successfully introducing a combined conference for moldmakers and injection molders in 2022, Plastics Technology and MoldMaking Technology are once again joining forces for a tooling/molding two-for-one.

3D printing finds its sweet spot in the area of prototyping and small to medium-sized production runs of geometrically complex parts and components with gaps, holes or voids. It is also the best fit for the manufacture or parts where the design will frequently evolve or where customization is required, as design changes can be accommodated even in production.

Join KraussMaffei for an insightful webinar designed for industry professionals, engineers and anyone interested in the manufacturing processes of PVC pipes. This session will provide a comprehensive understanding of the technology behind the production of high-quality PVC pipes: from raw material preparation to final product testing. Agenda: Introduction to PVC extrusion: overview of the basic principles of PVC pipe extrusion — including the process of melting and shaping PVC resin into pipe forms Equipment and machinery: detailed explanation of the key equipment involved — such as extruders, dies and cooling systems — and their roles in the extrusion process Process parameters: insight into the critical process parameters like temperature, pressure and cooling rates that influence the quality and consistency of the final PVC pipes Energy efficiency: examination of ways to save material and energy use when extruding PVC pipe products

Addressing hot-runner benefits, improvements, and everyday issues from the perspective of decades of experience with probably every brand on the market. Part 1 of 2.

Dead spots are any areas inside the hot runner that are mismatched or any turn in the melt channel that was created by cross drilling and plugs. The mismatch can create an area where plastic is unable to escape, causing it to degrade and carbonize over time—or for our FM, to hang up and break off later as the melt flows pass over it. The turns created by cross-drilling are very similar. Cross-drilling creates a sharp corner on the inside of the turn and a dead spot on the opposite side. The circular flow of plastic allows this area to be filled but doesn’t allow it all to be cleared out by the next shot, so the plastic just sits in that area and cooks. This can cause a small bit of carbon to break off, leading to contamination in your parts, and just like the mismatch, it can also allow for FM to hide and show itself again, making molders think they have an active contamination event.

Most obviously, 3D printing can make components either impossible or expensive and difficult to achieve using injection molding, such as components that are hollow in certain areas. This is possible, as in 3D printing material is added in layers, and material density of the core can be altered. So, not only can some areas be hollow, but other critical areas can be reinforced. This means that 3D printing is a key facilitator when it comes to lightweighting, but with increased strength.

In this collection, which is part one of a series representing some of John’s finest work, we present you with five articles that we think you will refer to time and again as you look to solve problems, cut cycle times and improve the quality of the parts you mold.

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?

At the end of the day, when something like metal makes its way into your hot runner system the best thing to do is to have the system completely cleaned in an oven or a fluidized bath. Since we all live in the real world, one that has doesn’t allow downtime, we may have to work through issues we’d prefer not to. Understanding how plastic flows can help you determine if you have some old FM coming through the system or there is an active contamination event.

3D printing also promotes what can be called the consolidation of complexity. The technology can combine parts and features in one build that would otherwise have to be post-processed or assembled using conventional injection molding and allied technologies. And, printed parts can be more ergonomic and incorporate multiple parts and features that would be impossible or prohibitively expensive to achieve via the fabrication of highly complex injection molding tooling.

This Knowledge Center provides an overview of the considerations needed to understand the purchase, operation, and maintenance of a process cooling system.

ABOUT THE AUTHOR: Robert Gattshall has more than 22 years’ experience in the injection molding industry and holds multiple certifications in Scientific Injection Molding and the tools of Lean Six Sigma. Gattshall has developed several “Best in Class” Poka Yoke systems with third-party production and process monitoring such as Intouch Monitoring Ltd. and RJG Inc. He has held multiple management and engineering positions throughout the industry in automotive, medical, electrical and packaging production. Gattshall is also a member of the Plastics Industry Association’s Public Policy Committee. In January 2018, he joined IPL Plastics as process engineering manager. Contact: (262) 909-5648; rgattshall@gmail.com.

Beyond non-costly part complexity, using 3D printing for production also facilitates nearly unlimited geometric freedom, exhibits very low to zero iteration costs, and has low downtime in the production cycle.

That is another reason why it can take a great deal of run time and unblocking of gates for contaminants to work their way out of a hot-runner system—and I haven’t even mentioned dead stops yet.

In a time where sustainability is no longer just a buzzword, the food and beverage packaging industry is required to be at the forefront of this innovation. By adopting circular packaging processes and solutions, producers can meet regulatory requirements while also satisfying consumer demand and enhancing brand reputation. Join Husky to learn more about the broader implications of the circular economy — as well as how leading brands are leveraging this opportunity to reduce costs, increase design flexibility and boost product differentiation. Agenda: The cost and operational benefits of embracing circularity Key materials in circular packaging — including rPET and emerging bioplastics How to design a circular food and beverage package Strategies for selecting sustainable closures to future-proof packaging solutions Optimization and streamlining of production processes for enhanced efficiency How Husky Technologies can enable your sustainable success

Successfully starting or restarting an injection molding machine is less about ticking boxes on a rote checklist and more about individually assessing each processing scenario and its unique variables.

Join Wittmann for an engaging webinar on the transformative impact of manufacturing execution systems (MES) in the plastic injection molding industry. Discover how MES enhances production efficiency, quality control and real-time monitoring while also reducing downtime. It will explore the integration of MES with existing systems, emphasizing compliance and traceability for automotive and medical sectors. Learn about the latest advancements in IoT and AI technologies and how they drive innovation and continuous improvement in MES. Agenda: Overview of MES benefits What is MES? Definition, role and brief history Historical perspective and evolution Longevity and analytics Connectivity: importance, standards and integration Advantages of MES: efficiency, real-time data, traceability and cost savings Emerging technologies: IoT and AI in MES

First let me say that it is never recommended to allow the FM, metallic or otherwise, to pass through a hot-runner system. The best course of action is to send the system to an oven or fluidized bath to rid the flow channels of all plastic and contamination. You could also purge a hot-runner system with a purging compound if this were a single-level mold but with a multi-level mold this is a much more difficult process to say the least. At the same time, we need to protect the supply chain whenever possible for our customers and consumers.

This is based on the fact that today, 3D printing technologies have been refined to such an extent that they are truly viable production technologies. Now the conversation among manufacturers is around the most judicious use of 3D printing for production, what its advantages are, where the sweet spot is in terms of preferable volumes, what are the opportunities that exist through it use, and what are the barriers to entry?

Additive technology creates air pockets in film during orientation, cutting down on the amount of resin needed while boosting opacity, mechanical properties and recyclability.

Resin drying is a crucial, but often-misunderstood area. This collection includes details on why and what you need to dry, how to specify a dryer, and best practices.

3D printing is a highly reliable, cost-effective and relatively easy-to-use production technology for small- to medium-volume applications and can rival injection molding.

The idea that 3D printing is a plug-and-play technology is a myth. Entry-level desktop model printers only require a modicum of knowledge to operate. But for production applications, achieving the necessary build parameters, quality, costs per part and timeliness of build requires a heap of experience, which subcontract agencies have in spades.

Shorter runs and more frequent mold changes have become business-as-usual due to many shortages. These shortages have extended from resins to the steel we use to build mold components and even to the labor needed to package product. Let’s just say that these are interesting times that call for creative solutions in order to stay ahead or as close to ahead as possible.

Best practice when experiencing foreign material contamination of a hot runner is complete disassembly and cleaning, but that isn’t always possible. (Photo: Tony Deligio)