For our most recent update, we researched the ice pop molds available and tested five new ones against our previous picks. During our last round of testing, we made three different types of ice pops: a version with just mango juice, fudge pops, and mixed-fruit pops (video). We used these recipes in order to understand how the molds would perform with different consistencies—simple, smooth pops, creamy pops, and chunky ones, respectively. We followed the molds’ specific cleaning and care instructions during testing, but we also put those that weren’t dishwasher safe through one final wash in the dishwasher to see how they would hold up to the occasional cycle.

An uncommon, but very serious crash can occur when a large mold is hung in the machine in two halves. If one of the halves is accidentally oriented 180° out of position and the setup man overrides the low-pressure setup mode because the mold won’t close, really bad things happen. On a couple of occasions, I have seen a molding machine with a bad hydraulic valve. The mold closed at full velocity and shook the entire building. But accidental mold crashes are thankfully infrequent and one-time events.

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

Shape: The shape of a mold can affect how pleasant your pop is to eat, as well as which recipes might freeze and release successfully. Pops that have a roundish shape and mostly fit in the mouth are easier to eat; if they’re too big or bottom-heavy, the bottom half might become a drippy mess before you get to it. Generally, smooth molds are the most versatile for a variety of recipes. “Molds that have a lot of elaborate detail to the shape will work best with mixtures that are going to freeze really solid, like fruit juice,” said Charity Ferreira, author of Perfect Pops. “Anything creamy or boozy or with chunks is not going to show much definition when you freeze it in a mold with a lot of detail.” She also told us that pops involving ice cream “or anything else that will freeze on the softer side” may be harder to extract from detailed molds. (In our own tests, we found that creamier pudding pops worked fine in the more elaborate molds we recommend but tended to lose detail faster than juice pops once they started melting.)

The ice pops we made in the Cuisipro Snap-Fit Circle Pop Mold broke in half almost every single time. They’re nicely shaped and a reasonable size, but we spent too long trying to get the little bit of ice pop stuck at the bottom of the mold to melt enough to drink.

If the material is highly abrasive, such as those with glass fillers, all the surfaces in contact with the plastic need to be through-hardened—the harder the better. That includes the sprue bushing and runner inserts, not just the cavities and cores. Abrasive materials can also dictate that the gate(s) be inserted because they will be the first thing(s) to wear out. Steels with high concentrations of carbon and chrome typically have good wear resistance. If the material is extremely abrasive, such as a thermally conductive material with silicon carbide filler, then one of the powdered-metal tool steels with a typical hardness value of about 60 Rockwell C could be best suited.

When you insert the plastic handles, they just rest jauntily on top of the liquid and don’t lock into place. That’s not a huge design flaw, but it is slightly confusing the first time you use these molds. The plastic sticks are shaped to correspond to each of the clownfish, shark, whale, octopus, scuba diver, and puffer fish molds, and a small symbol on each mold goes with a symbol on a stick (don’t overfill the molds, as the liquid will cover up the symbols). If you want to get the desired visual effect, you need to match the symbols, but rest assured that mixing them up isn’t that detrimental to the outcome of the final pop. In fact, we bet kids would be amused by the sight of the scuba diver with squid legs.

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

Pop molds generally come in one of three different materials: plastic, silicone, or stainless steel. Each has its own pros and cons, but generally we recommend plastic or silicone.

Tovolo also makes these molds in other shapes. Although we don’t recommend the tiki-shaped molds based on our tests (the grooves in each mold made it too difficult for us to release the pops), we imagine that some other, similarly shaped molds (such as the monster, sword, and zombie sets) would likely perform akin to the Penguin Pop Molds, as they don’t have too many grooves for the pop to get caught up in.

If you’re looking for impressive visuals in an even smaller size than the Tovolo Penguin Pop Molds offer, we recommend the Zoku Fish Pop Molds. The adorable aquatic figurines will delight little ones, and ours looked crisp and professional regardless of the pop recipe. It’s easy to pull the fish pops from their silicone molds, each of which holds about 1.5 ounces depending on the shape—a great size for toddlers. The molds are easy to overfill, though, and this is the only set we recommend that isn’t dishwasher safe. It also has a fairly large freezer footprint, although the wide, stable base does help prevent spills. The pops from these molds were the easiest to remove of any of the kid-specific molds we tried. If aquatic animals aren’t your thing, Zoku also offers similar molds in other shapes, such as dinosaurs or polar animals, that are likely to perform well, too.

The hardness of the plastic, as well as the hardness of the mold can dictate how quickly and how severely the mold will get damaged. If a hot bushing is drooling Ultem PEI in a P-20 mold, it won’t be long before you are grinding a few thousandths off the parting line to clean it up. I know moldmakers that intentionally make the mold cores 0.005 in. taller because they believe they will be grinding the parting line a couple of times over the life of the mold. But the hardnesses of the plastic and the steel are not the only factors that promote flash. The list of potential causes is exhaustingly long. Here are some of the more common ones:

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.

On hot days, few things are as satisfying as reaching into your freezer for a homemade ice pop—but only if you can extract that ice pop in one piece. Having a popsicle mold that’s easy to fill, store, and remove treats from makes all the difference. After researching dozens of popsicle molds, testing 31, and making almost 200 ice pops over the years (as well as eating enough of them to give a whole army a brain freeze), we’ve found that the Tovolo Classic Pop Molds make the most consistent and easy-to-eat pops of all the molds we’ve tried.

Lékué offers a few other shapes of pop molds. We chose to test the Tropical Fruit set so that we could try out one of the line’s sturdier (watermelon) and potentially more precarious (pineapple) shapes. If you’re interested in trying other Lékué silicone molds, the classic ones should work similarly to the watermelon shape, and other shapes (such as the cactus) should do at least as well as the pineapple.

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.

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.

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.

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The Tovolo Penguin Pop Molds are great for kids thanks to their slightly-smaller size and cute shapes. This set includes four silicone molds that rest on a sturdy plastic tray. Each mold makes a slightly different-shaped penguin, with a different hat or accessory, giving your kids a little surprise to look forward to or the chance to pick their favorite pop. The molds hold only about 2 ounces of liquid, making the pops just small enough for kids to enjoy without being overwhelmed. They’re a little fussy to fill, but the silicone is easy to peel off your frozen pops, not requiring any soaking or rinsing in warm water. And this set is a breeze to clean, as the entire thing is dishwasher safe. Tovolo offers similar molds in other shapes, too, such as dinosaurs or monsters; these molds would probably work about the same as the penguin molds, but we haven’t tested them ourselves.

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Durability: In our tests, we looked for molds that were sturdily built, with sticks that weren’t likely to snap in half and molds that wouldn’t shatter when dropped.

The Tovolo Classic Pop Molds unseated our former reigning champion, the Zoku Round Pop Molds, after a near-perfect round of testing. These plastic molds created consistent ice pops, with a classic tall shape and rounded top. Even with denser, heavier chunks of fruit inside, the pops didn’t break as often as those from other molds we tested. The design lets you remove the plastic molds from the tray one at a time, so you can easily dip or rinse an individual mold in warm water to release a pop without melting the rest. The reusable sticks have an effective drip catcher, too, and the entire set is dishwasher safe, so you’re dealing with less mess while eating and easy cleanup when you’re done.

The push-pop-style Zoku Summer Pop Molds functioned well, but they came with one major price to pay—the smells that silicone tends to pick up from a freezer. Although the silicone molds we recommend also acquire odors, you’re meant to remove the pops from those molds, and that way, you escape the smell. The Summer Pop Molds, on the other hand, stay with you as you’re eating, putting the smell right in your face the whole time. But if the smell doesn’t bother you, these tube-shaped molds do work well, with almost no real drippage.

Plastic molds are cheap and readily available, and overall the plastic molds we’ve tested over the years have performed well (our current top pick is plastic). The biggest downsides to plastic are that it’s prone to breaking if you drop it while it’s frozen, and that it sticks to frozen pops more than silicone—plastic molds need to be run under warm water until they release their precious icy cargo. Plastic molds work best for making smooth, simple shapes that can slide out easily.

The thickness of the molded part is important when it comes to selecting the best material out of which to make the cavities and cores. If the part is thin-walled, selecting a material with extremely high thermal conductivity may not be the best choice. The material can solidify too quickly during injection, and you can end up with a lot of short shots or injection pressures that exceed the machine’s capabilities. Conversely, if the part is extremely thick, the thermal conductivity of the cavity and core material is not nearly as important because the molded part forms an exterior skin, which acts as an insulating barrier. That’s why a graph of cooling time vs. wall thickness is not a straight line. It is an upwardly projecting curve.

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.

Wirecutter is the product recommendation service from The New York Times. Our journalists combine independent research with (occasionally) over-the-top testing so you can make quick and confident buying decisions. Whether it’s finding great products or discovering helpful advice, we’ll help you get it right (the first time).

If the injection or packing pressure is excessive, or if the clamp pressure is insufficient, the plastic will try to ooze out of the cavity. This usually results in the sharp-edged perimeter of the cavity starting to look like someone added a small radius to it. Over time, the cavity will have more and more flash growing around it. The problem with flash is that once the surface of a mold is indented, it never gets better. It can only get worse. It needs to be repaired and the root cause determined and corrected when it’s first noticed. Giving an operator a razor blade or some other tool to remove the flash is not an appropriate corrective action.

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

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

Each fruity silicone mold in this set is a separate piece, allowing you to easily stack them in the freezer. These fun shapes are simple to extract pops from and are fully dishwasher safe.

Despite their level of detail, we found the fish pops easy to unsheath from the Zoku silicone molds with a simple tug. It actually helps that the molds are firmly attached to their silicone tray, so the mold just turns inside out as you pull on the stick. And since you don’t need to run these molds under warm water to loosen your ice pops, it’s not a problem to remove one at a time. Although Charity Ferreira, the author of Perfect Pops, told us that creamier recipes often don’t show detail as well when placed in elaborate molds, we didn’t find that to be a problem with these molds.

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.

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.

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We found the molds somewhat difficult to clean. For one thing, this set is the only one among our picks that isn’t dishwasher safe. Even though we threw these pieces into the dishwasher and they held up just fine, we wouldn’t recommend regularly doing so. You also have to push each silicone mold inside out to ensure that you clean it thoroughly, and since the molds and the tray are all one piece, we found the whole thing a bit cumbersome to maneuver in the sink. Ultimately, though, cleaning wasn’t so much of a hassle that we thought it was a dealbreaker.

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For example, if a part design has sharp outside corners (meaning sharp inside corners in the mold) and is subjected to high injection pressures, it’s longevity could be very short due to the potential of fracturing. I’ve seen well-built, class 101 hot-runner molds fail after the first five minutes because the manifold filled up with plastic—snapping bolts and splitting plates apart. I have also seen dead-soft aluminum molds run trouble-free for well over a decade.

For something fun but not too childish, we recommend the 3.2-ounce Lékué Tropical Fruit Ice Pop Molds. These pricier molds come in the shapes of watermelon slices and whole pineapples, making cute yet sophisticated pops that would be great for a party. They don’t have a tray to rest in and must lie horizontally as a result, but the molds are lidded and stackable, allowing you to arrange them in your freezer as you see fit. The silicone is easy to peel off, and each piece is dishwasher safe. The reusable stick has no drip catcher, so dole these pops out to kids with caution—messes may ensue.

Acknowledgement: I want to thank Brenda Clark of Hasco America; Patricia Miller of Uddeholm; Roy Glenn, retired mold builder and designer; and Rick DeBeer, retired from LyondellBasell, for their knowledge and insight, which helped me compose this article.

All of our picks come with reusable plastic sticks, but if you, like Ferreira, prefer the look and feel of old-fashioned wooden sticks, you can still use those with most molds. Ferreira taught us a hack she uses to modify molds that aren’t originally designed for wooden sticks: “You can cover the top of the mold with foil, make a slit in the foil, and insert the stick. That holds the stick in place while the mixture freezes.”

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.

Personally, I have a passion for using thermally conductive materials, especially in hard-to-cool areas. Not because they are great at reducing cycle time, but because they are great at achieving uniform cooling. Non-uniform part cooling invites part warpage, and warped parts are often a rejectable condition. Table 2  gives approximate thermal-conductivity values for various mold materials. These values can vary widely depending on the manufacturer, heat treatment and operating temperature.

Size: For adults we preferred molds that held between 3 and 4 ounces of liquid. Larger pops can become tiring and messy to eat, and less than 3 ounces just isn’t enough unless you’re exclusively feeding toddlers. But if you are feeding toddlers or kids, we’ve found that the ideal size ranges between 1.25 and 2 ounces.

The watermelon-slice mold is about 6 inches long (including the reusable stick), 3 inches wide, and 1¼ inches tall, while the pineapple mold measures about 7 inches long, 3¼ inches wide, and 1¼ inches tall. Their footprint in a freezer is minimal since you can stack molds of the same shape together, and you can choose to freeze just a couple at a time, so they give you lots of flexibility to work with your space. The Lékué Tropical Fruit Ice Pop Molds are also dishwasher safe.

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

The PLASTICS document is meant to be a guideline for purchasers of injection molds, and it should be renamed accordingly—guideline. The problem is that many people consider the stated minimum cycle counts to be factual, if not contractual. And that can lead to problems down the road. What happens to a class 101 mold at a million and one cycles? The customer pays for all the maintenance and repairs to the mold—regardless of how small or how large the cost? What happens at 999,000 cycles if a cavity cracks? Does the moldmaker have to replace it at his cost? As unpleasant as this topic is, it may be worth setting some initial ground rules with your customers.

A very common cause of mold damage is due to galling. When two pieces of steel rub or slide against each other, there is a risk of them metallurgically bonding together. You can usually hear the components squeaking shortly before they seize up. Galling can occur at any time—from the initial mold sampling up to 1 million cycles later. Everyone from the machine operator to the plant manager should be aware of what this sound means. Recognizing a galling situation early can reduce the amount of mold damage.

These clever under-the-sea molds make even-smaller-than-average pops, so they’re more manageable for younger kids to finish. The silicone molds release easily, but they’re also easier to overfill than our main pick.

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For our 2015 update, in order to ascertain which features were most important in an ice pop mold, which materials work best for a home cook, and how to make the best ice pops, writer Molly Simms interviewed Reuben Ben Jehuda, owner and co-founder of the Popbar chain, and Charity Ferreira, who penned the 2011 cookbook Perfect Pops. For the original 2013 guide, writer Jamie Wiebe spoke with Douglas Goff, a food scientist specializing in ice cream at the University of Guelph, and David Carrell at Brooklyn-based pop shop People’s Pops (now closed).

In our tests, filling these molds was a breeze. Due to their classic shape and lack of tiny grooves or intricate designs (we found ice pops got trapped in molds with too much detail), these molds were perfect for plain-juice pops, versions with whole pieces of fruit, and fudge pops alike. The molds lock into place on the tray, as well, so we didn’t ever worry about a mold slipping out of place on the tray the way we did with one of our picks for kids, the Tovolo Penguin Pop Molds.

Cute and fun, this set offers unusual shapes and an easily peelable silicone mold. The medium size is great for big kids (we have an even smaller pick for younger ones).

I have already mentioned polishability, thermal conductivity, hardness and corrosion resistance. But what about toughness, compressive strength, wear and abrasion resistance? These are important properties to consider as well, especially when two pieces of steel slide against each other, like a cam, lifter or shutoff. The old rule of thumb says that if different steel types are used and there is a 10-point Rockwell C differential between them, everything will be fine. That rule of thumb doesn’t always hold true—especially if the forces are high and the contact area is large. O-6 and A-10 steels are good for sliding applications because these two steels have high concentrations of graphitic particles in their microstructure. O-1, O-2, D-2 and S-1 are also good steel types for sliding applications.

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The Norpro Frozen Ice Pop Maker quickly became guide writer Haley Sprankle’s enemy during our tests. The experience was like putting a fitted sheet on a bed, but in reverse: The lid to the mold was almost impossible to remove, with each corner being so dependent on the others to perfectly pop off. At one point, we needed two people working together to lift the lid. Although this mold used to be our pick for a crowd, these days we think you’re better off investing in two sets of the Tovolo Classic Pop Molds for an easier time.

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

A pre-hardened stainless-steel mold base is an even better solution. The thermal conductivity of stainless isn’t as good, but it usually doesn’t matter for a mold base. I always wondered about moldmakers who prefer steel types that have good weldability. While that is a good property to have, it shouldn’t be a guiding factor. Some steel preferences are based on years of experience. Some are based on how easy they are to machine, or how much they change size or warp during heat treatment. Usually, the commonly used steels are more than adequate for most parts. But occasionally the properties of the steel should be given greater consideration.

We’ve tested 21 ice cream makers, and our favorite is the Cuisinart ICE-21. It’s a great tool for beginners and pros alike.

Easy to clean: We looked for molds that were easy to clean. If a mold has a lot of little pieces and crevices, cleaning them by hand can be time consuming and complicated. We did pick some silicone molds that were more detailed, but none of them were too cumbersome to clean, possibly because it’s easier to get at crevices when they’re made of flexible silicone. It’s also nice if you can just toss a mold in the dishwasher, but we didn’t rule out any molds that weren’t dishwasher safe.

The Tovolo Classic Pop Molds consistently produced the most easy-to-remove 4-ounce pops in a classic shape (rectangular, with a rounded top) that's enjoyable to eat. With the assistance of a little warm water, our pops came out of their plastic mold smoothly, never breaking during any of our recipe tests. The drip catcher is the most effective of any we’ve come across, requiring a full 90-degree tilt to spill some melted pop on yourself. On top of that, the molds, reusable sticks, and tray are all dishwasher safe and durable.

Cute and fun, this set offers unusual shapes and an easily peelable silicone mold. The medium size is great for big kids (we have an even smaller pick for younger ones).

In previous tests, we used four different recipes in each mold: pure orange juice, Creamsicle-like yogurt pops, mixed fruit, and fudge. We did two rounds of pop testing in each mold, and then we hand-washed all the molds to assess how difficult they were to clean and care for.

Though some of our picks are pretty compact, they still might be more than some households need. If you don’t have the cabinet space to store the molds when you aren’t using them, or if you don’t anticipate getting enough use out of an ice pop mold to justify storing one in the first place, Fany Gerson has the perfect suggestion, something that you can find in your local grocery store: As an alternative to buying a mold, Gerson recommends buying Dixie cups and disposable wooden sticks. Since the cups are disposable already, you can just peel the paper off and enjoy your pop without struggling to free it.

The penguin shape itself is simple to eat, and the reusable sticks have flat drip guards at the base of each pop. These drip guards aren’t as effective as the cup-shaped drip catcher on the Tovolo Classic molds, but they do protect fingers from coming into direct contact with the pop.

Like some other silicone molds, the Fish Pop Molds do have a slight chemical odor out of the box, but that should go away after the first few times you wash them.

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

Reusable sticks: We prefer molds that come with reusable sticks, since buying wooden sticks and inserting them in pops can be a hassle, especially if you run out of them and can’t make pops spontaneously. In our tests we looked for reusable sticks that felt smooth and not too pointy in the mouth during the final stages of eating so that they didn’t present a hazard to children.

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.

The Tovolo Penguin molds hold about 2 ounces per pop, making an icy treat that’s small enough not to be overwhelming for kids. And they come in unique, cute shapes—each penguin has its own look—that are fairly easily removable from their individual silicone molds. The sticks are reusable, and each piece of this set is dishwasher safe.

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

While it’s true that heat-treated tool steels with high compressive strength can delay the amount or severity of flash damage, it cannot make the mold impervious to damage. Figure 4 shows a severely hobbed parting line of a pre-hardened 28-32 Rockwell C mold caused by nozzle strings. Generally speaking, the harder the tool steel is, the more brittle it is. Obviously, there is a tradeoff when it comes to the physical properties of metals. Depending on several factors, you might need to consider using a more ductile material, or making a spare cavity set as insurance.

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.

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

Just like an airplane, car, boat or motorcycle, a mold can potentially last forever if it is maintained properly and repaired when necessary. The only time a mold is considered unusable or has reached the end of its lifespan is when the repair cost exceeds its worth. In addition to the part and mold complexity, the mold’s longevity is based on many other factors, including (but not limited to) the mold design, steel selection, quality of the mold components and construction, the molding machine it runs in, molding material type and molding process used to make the parts, as well as the mold installation, removal, maintenance and storage.

2.  What is the part used for? If it’s a medical, optical or automotive part, there’s a very good chance that the mold is required to be made of ESR (electroslag reduction) stainless steel for cleanroom conditions and optical polishing or mold texturing.

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

The yield strength of P-20 steel is about 125,000 psi.  The yield strength of 1030 and 4130 steel is about 64,000 psi.  This equation doesn’t even include the added force applied to the debris due to the closing speed and momentum of the moving platen.  Figure 3 shows what gate flakes can do to a mold when the applied pressure is considerably greater than the yield strength of the steel.

To properly understand the differences in performance between PET and PBT we need to compare apples to apples—the semi-crystalline forms of each polymer.

It’s best to wash pop molds thoroughly after every use. Most of our picks (except for the Zoku Fish Pop Molds) are entirely dishwasher-friendly, which makes cleanup easy if you own a dishwasher. If you prefer hand-washing your molds, we’ve found that rinsing molds shortly after using them prevents gunk from drying on if you can’t thoroughly wash them right away. You should also take care not to use harsh scouring pads or steel wool while cleaning, so as not to scratch the molds (this goes for both plastic and silicone). And keep silicone molds far from any knives or other pointy objects in your sink or dishwasher, so you don’t accidentally puncture them.

Like the Tovolo Classic molds, these molds are designed to let you remove them individually from the tray. When filling the Tovolo Penguin molds, you must first place each individual silicone penguin in a cylindrical slot on the tray. But be aware that there’s nothing to secure each silicone mold in place on the tray aside from the slots themselves: You need to fill the molds carefully so that the edge of the silicone mold doesn’t tilt off-balance and slip through the slot in the tray, causing a spill. Once you’ve filled all the molds, you top each one off with a playful stick that looks like a little iceberg. Take care not to overfill the molds before placing the sticks; if the molds are too full, the pops will freeze over the drip guard, leaving no barrier between your fingers and a melting pop. It’s a good rule of thumb to fill the mold to right before it widens at the top, so the stick can fit snugly.

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

If you’re looking for a smaller alternative for kids, we recommend the Zoku Fish Pop Molds. The aquatic shapes turn out remarkably crisp and professional looking, true to the photos on the box. In our tests, the silicone molds worked impressively well, seamlessly releasing each pop, and the 1.25- to 1.5-ounce size of each pop is just the right size for toddlers on up, though this smaller capacity does make the molds easy to overfill and less versatile for the whole family.

These plastic molds make a traditionally shaped ice pop that comes out smoothly. The individually removable molds fit in a narrow tray, taking up minimal freezer space. And the whole set is dishwasher safe.

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

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.

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.

Although the Lékué molds are a little more expensive, they’re a great option for adults who want to add a little whimsy to their summer snacks. They’d be especially fun to use for boozy pops at a party, although if you go that route, Fany Gerson, owner of La Newyorkina and author of Paletas: Authentic Recipes for Mexican Ice Pops, Shaved Ice & Aguas Frescas, recommends pouring your favorite adult beverage into a glass and then dipping your ice pop in rather than trying to make pops with alcohol in them (since alcohol doesn’t freeze well). “It starts to melt, so it kind of has different stages of how you enjoy it, but it’s delicious,” she said. “So first, you dip the popsicle in the alcohol—you suck the popsicle, you get that juice—but then it starts to melt, and then it creates another drink.”

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.

Haley Sprankle was an updates writer at Wirecutter covering kitchen gadgets and financial content. She loves French bulldogs, French tucks, and french fries. It’s a wonder she hasn’t been to France yet, but it’s next on her to-do list.

In our tests, the Tovolo Groovy Pop Molds were not good at creating anything but fruity pops. The stick tended to pull out sans ice pop—either that, or the pop wouldn’t come out at all. The frozen molds also shattered into small pieces when we dropped them on the floor with ice inside.

Although the Tovolo Classic Pop Molds performed the best overall among the “classic” pop molds in our tests thanks to their great shape, compact tray, and effective drip catcher, plastic molds in general can sometimes be finicky to remove a pop from. Whereas some of our tested silicone molds allowed us to pull the pops right out without any hesitation or a dip in warm water, sometimes we had to work a little harder to jimmy the pops out of the Tovolo Classic molds. But since these molds were still better than many of the other plastic molds we tested, we don’t consider that bit of extra effort to be a dealbreaker.

Once you’ve consumed the pops, you can toss both the molds and the tray into the dishwasher and let it work its magic. If you don’t have a dishwasher, these pieces are fairly simple to hand-wash—they don’t have many crevices for you to worry about reaching. The ease and convenience of the Tovolo Classic Pop Molds make them the best all-around popsicle molds we’ve tested, hands down. Though our former pick, the Zoku Round Pop Molds, were also easy to use, they weren’t dishwasher safe, nor did they have an effective drip tray.

We looked for pop molds that would be pleasant to use from start to finish—filling the mold, removing the pops, and cleaning up after—and found that materials, shape, and a few thoughtful design features were the biggest determining factors.

A moldmaker’s objective is to maximize the performance of a mold to achieve the lowest possible total cost per part based on the intended lifespan of the project. That analysis should include the goal of minimizing the cost to maintain the mold. Therefore, when reviewing a new project, moldmakers will wisely ask:

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.

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If you prefer a round pop: We also retested our former favorite, the Zoku Round Pop Molds, in 2021, and appreciated the unusual, chic shape and easy release of its pops. But again, the mold isn’t dishwasher safe like most of our current picks. Readers have noted, too, that the resulting pop shape can be difficult to eat, and the drip catcher is relatively ineffective.

The Tovolo Penguin Pop Molds and their tray are bigger and a little clunkier than our top pick, even though they make just four pops instead of five. The tray is about 10½ inches long, 4 inches wide, and 5 inches tall. It’s also bigger than the Zoku Fish Pop Molds tray, which makes six pops, albeit smaller ones. But unlike with the Fish Pop Molds set, you can throw this whole thing—penguin molds, reusable sticks, and all—straight into the dishwasher.

If you'd like a sleek pop: We also tested the Zoku Mod Pop Molds in 2021. They were comparable to the brand’s Classic Pop Molds, except the pops they made had more squared edges. Yet again, these are a great option and performed just as well as the Tovolo Classic molds with each of our testing recipes, but they’re not dishwasher safe.

4.  Is there a dimensioned 2D drawing of the part? I have seen too many jobs quoted strictly based on a 3D CAD model. CAD models do not specify the tolerances for critical dimensions. Nor do they specify the surface finish, aesthetic areas that cannot have gate or ejector-pin marks, secondary operations, mating parts, etc. 2D drawings almost always help the moldmaker decide the best way to design and build a mold—or if the part is even moldable to the stated specifications.

The real mold killer—for any mold, of any complexity—is parting-line flash.  When plastic or other debris adheres to the parting line of a mold, it can deform the mold by leaving an impression or indentation. If you think about it, when debris is sandwiched between two flat surfaces and is exposed to a few hundred tons of clamp pressure, it has nowhere to go but in.

Each fruity silicone mold in this set is a separate piece, allowing you to easily stack them in the freezer. These fun shapes are simple to extract pops from and are fully dishwasher safe.

•  Inferior mold design  •  Inferior mold construction  •  Insufficient mold-plate thicknesses  •  Insufficient support-pillar area  •  Lack of parting-line relief  •  Improper mold setup  •  Insufficient clamp pressure  •  Excessive clamp pressure  •  Cavity imbalance  •  Poor processing parameters  •  Excessive injection or pack pressures  •  Low material viscosity  •  Insufficient venting  •  Excessive vent depth  •  Using adhesive labels as vents  •  Machine bushing wear  •  Machine platen wear  •  Lack of alignment  •  Worn shutoffs  •  Abrasive molding material  •  Abrasive material fillers  •  Nozzle stringing  •  Sub-gate flaking  •  Sticking parts or runners  •  Rust or corrosion  •  Lack of preventive maintenance

The quirky Lékué Tropical Fruit Ice Pop Molds charmed us during our recent tests. They’re great for both kids and adults, offering something cute but not childish. The tropical-fruit set of silicone molds includes two shapes—a watermelon slice and a pineapple—that are perfect for summer snacking. (Lékué also sells molds in other shapes, including strawberries and cacti.) Though they have no tray, the lidded molds (which come in a set of four or eight depending on where you find them) are small and stackable, leaving you plenty of freezer real estate. The silicone is easy to peel off the pops, the reusable stick fits securely in a slot, and each piece is dishwasher safe.

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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

At about 9 inches long, 3 inches wide, and 6 inches tall, the set doesn’t take up too much space overall, especially considering it makes five full-size pops. In contrast, the Tovolo Penguin Pop Molds set that we recommend is 1½ inches longer and 1 inch wider, and it yields only four smaller pops. Thanks to the Tovolo Classic set’s slim profile, you can slide it into narrower spaces in your freezer, so there’s less need for you to rearrange bags of frozen peas or a chuck roast you may have forgotten about.

Driven by brand owner demands and new worldwide legislation, the entire supply chain is working toward the shift to circularity, with some evidence the circular economy has already begun.

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

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

There are many factors that determine the longevity of a mold. Part complexity, which dictates mold complexity, is probably the biggest factor. A mold that produces a flowerpot, 5-gal bucket or a Frisbee can last a very long time. But more complex molds, such as those with cam action, unscrewing mechanisms, collapsible cores, contoured parting lines, sliding shutoffs, etc., will not last nearly as long because there are more component parts that can wear, break, gall, or seize. Just because a mold is made of heat-treated tool steel doesn’t mean it’s going to pump out hundreds of thousands of parts.

Writer Haley Sprankle has tested products for Wirecutter's guides to kitchen towels, dish racks, and oven mitts and pot holders. While working on the 2021 update of this guide, Haley interviewed Fany Gerson, owner of La Newyorkina and author of Paletas: Authentic Recipes for Mexican Ice Pops, Shaved Ice & Aguas Frescas.

Wear and galling explain why there has been a lot of attention given to various surface coatings and surface treatments, as well as the metallurgical compatibility of different types of mating steels.

The pops themselves are easy to eat, with a classic shape and a drip catcher attached to the handle that stops potential messes effectively. Although we did still manage to spill some melted pop, that was after we tipped the pop completely to the side when trying to finish it (the fudge pops were just that good). If you hold your pops mostly upright or even at a slight slant, you should have few issues with the drip catcher.

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.

These plastic molds make a traditionally shaped ice pop that comes out smoothly. The individually removable molds fit in a narrow tray, taking up minimal freezer space. And the whole set is dishwasher safe.

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).

The only time a mold is considered unusable or has reached the end of its lifespan is when the repair cost exceeds its worth.

Many of the molds we’ve tested over the years are now out of stock or discontinued. Here are our thoughts on the ones that are still available.

It’s safe to say that no matter what age kids are, they love a good ice pop. The Tovolo Penguin Pop Molds and the Zoku Fish Pop Molds are both fun options for kids. The Tovolo Penguin molds are slightly larger than the Zoku’s, and can be removed from the tray, whereas the Zoku Fish Pop Molds are smaller and fixed in their tray. Both mold sets are made of silicone with a hard-plastic tray, have drip guards, and release their pops easily. Both sets come in a few other shapes, too.

These plastic molds make a traditionally shaped ice pop that comes out smoothly. The individually removable molds fit in a narrow tray, taking up minimal freezer space. And the whole set is dishwasher safe.

As with the Tovolo Penguin Pop Molds, you have to peel the silicone off the pop when you’re ready to eat it. But unlike other silicone molds we’ve tested, this mold design also requires you to push the stick forward through its slot in the silicone to release the whole thing. At first, we thought this task might be challenging, but once we got the hang of the process, it wasn’t so bad. Between the two mold shapes (pineapple and watermelon), we found the pineapple mold a little more finicky to use: When we made mixed-fruit pops, the bulkier chunks of fruit made it too easy for the top of the pineapple shape to break off its base. Even if we extracted a pop from the mold just fine, sometimes the top would break off while we were eating. We imagine you might run into the same issue with the cactus-shaped pop molds. Fortunately, the pineapples held up well with strictly liquid recipes. With the watermelon-shaped pop molds, we had no problems with the chunky-fruit or liquid recipes.

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.

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.

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.

Cute and fun, this set offers unusual shapes and an easily peelable silicone mold. The medium size is great for big kids (we have an even smaller pick for younger ones).

Toughness, which is basically a combination of strength and ductility, is important for tall, free-standing cores, as well as cavities with sharp inside corners where cracking from molding pressures is a concern. H-13 has very good toughness properties. S-7 is also good.

I have a 1982 edition of the Classifications of Injection Molds for Thermoplastic Materials by the Society of the Plastics Industry (now the Plastics Industry Association, or PLASTICS). My edition defines the construction requirements for various types of molds for machines up to 400 tons and labels them type 101 through 105. It also has three types of quick-change mold inserts, which are labeled type I through III. It specifies similar classifications for molds that require machines with 400 tons or more of clamp pressure. Each type has a specific number of cycles a mold is capable of producing. Table 1 summarizes these classifications and lifespan quantities.

Let’s do some simple math. Assume a sub-gated part leaves 1/16-in. diam. flakes on the parting line. A 1/16-in. diam. flake has an area of 0.0031 in.2.  The mold is in a 500-ton press. Pressure = Force ÷ Area so in this case:

Silicone is a great material for ice pop molds since it’s flexible, doesn’t become brittle at freezing temperatures, and simply peels away from frozen matter, making pop removal a cinch even when you’re dealing with complex shapes. As food scientist Douglas Goff told us, “Plastic under a microscope is very rough, with lots of nooks and crannies, so ice can easily adhere to it and that makes withdrawal of a frozen novelty out of a plastic mold difficult. Silicone repels water, so the lack of stick is mostly due to the lack of interaction between water/ice and silicone at the surface of the mold.” Durability can be an issue—accidentally puncture these molds with a sharp object in the dishwasher, cabinet, or sink, and they’re permanently out of commission. Plus, silicone can emit a not-too-pleasant smell and is more likely than plastic to hold on to the odors of pops past (or anything else in your freezer). But overall, the benefits of silicone (and the fun shapes it can produce) make it a good alternative to plastic.

No matter the recipe, our pops came out quickly and easily after we soaked the Tovolo Classic mold in warm water for about 10 seconds (you can’t peel the mold off in the same way you can a silicone mold). This wasn’t the case with many other molds we tested—one competing set even needed two people working together to release the pops. We also appreciate that the Tovolo Classic design allows you to take out one mold at a time instead of having to soak an entire tray of molds in warm water to remove the pops (as we had to do with one of our previous picks, the Norpro Frozen Ice Pop Maker); this way, you can have one and save the rest for later, eat five at once with a larger group, or go for any option in between.

If you want an even number of pops: The Zoku Classic Pop Molds, our former runner-up pick, were out of stock for most of the spring and summer of 2020. Although such scarcity can be common for seasonal items, the Tovolo Classic Pop Molds haven’t had that problem. We retested in 2021 when the Zoku classic molds became available again, and found they performed identically to our top pick, the Tovolo Classic, easily releasing the pops after 20-30 seconds under running water. If you can find the Zoku set in stock, we like that it makes six ice pops instead of the Tovolo’s five. But unlike the Tovolo molds, these aren’t dishwasher safe.

Every customer I’ve ever had always asked how many parts their mold could make. Most moldmakers will respond to that question by saying something like, “Well, you paid for a Class 101 mold, so it should produce up to 1 million cycles.” Obviously, that answer is based on the PLASTICS mold classifications. While the classifications and the requirements for those classifications are excellent, I don’t agree with specifying the number of cycles each type of mold should be able to produce.

These clever under-the-sea molds make even-smaller-than-average pops, so they’re more manageable for younger kids to finish. The silicone molds release easily, but they’re also easier to overfill than our main pick.

Though premade Popsicles and other ice pops are easy to find, making them at home is the perfect activity for frozen-dessert fans who want to experiment with flavors and creative recipes. If you don’t have the space or the budget for an ice cream maker, a set of molds and a waiting freezer are all you need to become a frozen-treat maestro. The process is also a fun and simple kitchen project for kids or adults and can be customized for those who have dietary restrictions or who want something with less sugar than is found in the pops you can buy in the store. Plus, if you eat a lot of ice pops, making your own can be a lot cheaper in the long run than buying them.

Tovolo’s Jewel Pop Molds are too small, capable of holding only 1 ounce of liquid. Reviewers say that the pops are difficult to get out of the tray, and that the plastic stick tends to break in half.

Although the penguin pops don’t come out instantly with a simple tug like the Zoku-mold fish pops do, all you have to do to remove each penguin is peel off the silicone gently to ensure nothing gets stuck in the mold—no warm-water dip required. Still, the details in the penguins mean they aren’t ideal for a pop recipe that includes big chunks of fruit or other solid ingredients. In our mixed-fruit pop (video) tests, the whole grapes and blackberries made it difficult for us to fill the molds and remove the pops, while smaller pieces of fruit such as raspberries, blueberries, and sliced strawberries were much easier to work with.

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.

ABOUT THE AUTHOR: Jim Fattori is a third-generation molder with more than 40 years of experience in engineering and project management for custom and captive molders. He is the founder of Injection Mold Consulting LLC in Pennsylvania. Contact: jim@injectionmoldconsulting.com; injectionmoldconsulting.com

Supposedly, the classifications were updated back in 1996. More recently, there was an article in the August 19, 2021, edition of Plastics News mentioning that these standards are once again in the process of being updated by a team of industry leaders, association members and select members of the American Mold Builders Association. We should applaud their efforts to further improve this important document.

1.  What is the expected annual quantity? This helps the moldmaker decide the mold classification and the number of cavities required to meet those annual quantities.

Some of the common causes for a mold’s decreased longevity are due to accidents on the production floor. The folks in the trenches describe such events as “crashes.” One of the most common crashes involves a cam that is out of position—usually after cleaning the parting line or removing a part, or simply because the cam retention device was too weak, and the cam slid out of position. When a cam is out of position, the angle pin does not line up with the hole in the cam and then—crash—it snaps like a twig. If the angle pin hits the top of the cam, it’s usually not a big deal. Simply replace the pin. But if it hits any cavity impression, that’s going to end the production run and cost a lot more to repair. Another common type of crash is handling a mold with one eyebolt and no safety strap. An unsecured mold half can easily hit the ground well before you can yell “Look out!”

3.  What is the molding material? If it’s a corrosive resin, such as rigid PVC, the only good option is to make the mold out of stainless steel. I say the only good option because nickel and other coatings do not protect carbon steels from PVC gases for very long. If you think that stainless is too expensive, consider the cost to remove the worn or flaking plating, re-polishing the cores and cavities and then re-plating the mold.

It’s Chill Week here at Wirecutter, and we have plenty of tips and treats to help you cool down, from canned cocktails to a possible cure for night sweats.

We found it pretty simple to fill these molds when making our different recipes. The main issue to look out for is that you need to put the reusable stick in its slot before you fill the mold with juice—otherwise the juice leaks out of the slot (we may or may not have spilled mango juice all over the kitchen table during testing). You should also avoid overfilling each mold, so you can place the lid on top without making the liquid overflow. Keep in mind too that the flexible silicone molds are a little unstable, so you need to be careful not to spill the liquid when transporting them to the freezer. It might help to stack them on a tray first.

Lékué’s pop sticks also lack a drip catcher, so if you’re serving these pops to kids, you may want to have some paper towels on hand. No drippage was too egregious during our tests with adults—the results were similar to what you would get with any pop you might buy at the grocery store.

Each fruity silicone mold in this set is a separate piece, allowing you to easily stack them in the freezer. These fun shapes are simple to extract pops from and are fully dishwasher safe.

If you want simple pops with a cute factor: In the cute-for-kids category, we give an honorable mention to the Cuisipro Mini Pop Molds set, which features a small, unobtrusive drip tray and makes small pops that are just the right size for kids. Each stick is shaped like an animal—we tried the Safari collection—and the molds have interlocking segments that allow them to fit together, making them more stable for pouring and placing in the freezer. At four pops for $17 at this writing, these molds are not the cheapest options, but they felt well made, and the resulting egg-shaped pop was easier for our testers to eat than the ultra-round Zoku-mold pops. The handles also fit snugly onto the mold, making them less prone to spillage when we were transferring them from the countertop to the freezer. Still, the resulting pops were nowhere near as cute as the Zoku fish pops, so these molds ultimately failed to make the cut.

5.  Is there a target price for the molded part? This is a common question for thin-walled and commodity parts, such as caps and closures, where cycle time is critical and the need for a hot-runner system is paramount. High-thermal-conductivity materials such as copper alloys may be required. Unfortunately, too few moldmakers ask this question—unless they are also going to be the molder.

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

Easy-to-use design: A tray helps prevent pops from falling over and keeps your freezer organized. Even better is a tray from which you can easily remove individual pop molds; when all the molds are connected, it can be quite difficult to remove just one pop without disturbing the rest—particularly if the mold is made of plastic and requires some running under hot water to release the icy treat. Another helpful feature that some sets (including our main pick) have is a built-in drip guard on each stick to collect sticky drops before they hit your shirt.

Stainless steel molds are the most difficult to find and can cost more than a novice pop maker may be willing to spend. Steel is durable and doesn’t retain any off scents, but it’s not flexible, so you have to run the mold under warm water to remove your pops. Ultimately, we haven’t found any stainless steel molds we’d recommend.

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.

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

The Tovolo Tiki Pop Molds were too cute not to test, but with each and every recipe we tried, it was just too difficult for us to get the mold off the pop, whether we pulled or peeled (the latter is the recommended removal tactic). The size and the level of detail seemed to make it too tough for us to remove the ice pop cleanly.

If you’re bothered by the smell that silicone tends to retain, there are tons of tricks you can use to get rid of the odor. If you can separate the silicone pieces from any plastic ones, try heating the silicone parts in an oven at low temperature to bake the smell out. If you can’t detach the silicone from the plastic, you can instead try soaking your molds in a 50-50 mixture of white vinegar and warm water.

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.

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.

These clever under-the-sea molds make even-smaller-than-average pops, so they’re more manageable for younger kids to finish. The silicone molds release easily, but they’re also easier to overfill than our main pick.

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

Proper steel selection plays a critical role in the longevity of a mold. Most moldmakers have their “go-to” types, such as 1030 or 4130 for the mold base and P-20, 420 or H-13 for the cavities and cores. 1030 and 4130 are good steel types for mold bases, but if the project needs to last for several years, or if the water quality in the molding facility is prone to calcium deposits, the mold base should be electroless nickel plated.

Figure 1 shows a cavity set for a toy soldier. It was made in 1955 by hobbing blocks of copper. Hobbing is a manufacturing method rarely used today. Non-alloyed copper is also rarely used today because it is extremely soft. The figurine in Fig. 2 (left) was originally molded out of PS. The figurine in Fig. 2 (right) was cast out of liquid silicone material a few weeks ago on my desk. There’s a little flash on the cast part, but the “clamp pressure” was only about 10 lb—generated by a few rubber bands. The point is that part geometry is where it all begins, and oftentimes, defines when it all ends.

Pop molds aren’t must-have kitchen items like saucepans or can openers—most home cooks function just fine without them. But when summer rolls around and you have kids or overheated party guests at your house, you’ll be very glad you own them. Nothing tastes better on a muggy day than a fresh, mouth-numbing ice pop, pulled right out of the freezer and eaten under a patio umbrella.

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.