The foam made from it is closed-cell and waterproof, its cells are tightly connected, giving the foam a high tensile strength and making it strong and durable.The main benefit of injection molded foam is that its cycle is way faster; the foam and product are both manufactured simultaneously, as this process doesn’t require die-cutting or compression molding. Also, given its really high expansion rate, the products manufactured are self-skinning, meaning that they have a great reproduction of surface detail.

If you need an electronics housing or similar box-shaped part, you can either sink the wall cavities deep into the mold base, requiring long thin tools to machine ribs into the mold, or machine the aluminum material down around the core and mold the part around it. The latter approach is known as a core cavity, and is a far more cost-effective method of molding tall walls and ribbed surfaces. Better yet, this makes it easier to provide smooth surface finishes, adequate venting, improved ejection, and can eliminate the need for super-steep draft angles.

Textured surfaces, molded part numbers, and company logos look cool, but be prepared to pay a bit extra for these and other non-mission critical features. That said, permanent part numbers are a requirement for many aerospace and military applications. Use a mill-friendly font such as Century Gothic Bold, Arial, or Verdana (san-serif fonts), keep it above 20 pt., and don’t go much deeper than 0.010 to 0.015 inch. Also, be prepared to increase draft if part ejection is a concern.

Everyone wants to save money on manufactured parts. It sounds simple, but one of the easiest ways to reduce price-per-piece cost in injection molding is by increasing part quantity. That is because the initial upfront cost to design and machine the mold amortizes over more parts. At Protolabs, for example, up to 25,000 parts or more can be molded from the same tool.

Tough Black (Loctite Henkel 3843) and Ceramic-Filled (BASF 3280) are two new advanced photopolymer materials now available for 3D printing.

At J-CAD Inc. we are not specific about the form in which you provide us information about your project design. It could even be hand drawn, we don’t mind. We will convert it to a 3D file required for mold making and injection molding mass production. We will work with you to ensure that the design is optimized for the purpose for which it is intended. Our experienced team of highly skilled designers will help you bring out the best out of your product.

If you have any question just get in touch with us! At J-CAD Inc. we’ll be glad to help you with your project. Call us 1-888-202-2052 or email jason@jcadusa.com

Post Mold Stability Injection molding gives EVA Foam parts a very soft and malleable body after finishing their molding cycle. Because of this malleability a cooling fixture is sometimes required during the post-molding phase.

One interesting fact about flexible foam is that it contours around molds, allowing you to take shapes and make flexible objects that can easily be used for production items. These are usually produced with silicone molds, but urethane or other molds Keep reading

Pretty parts are nice, but they often require bead blasting, EDM, or high mold polish to achieve an elevated level of cosmetic appearance. This drives up tooling costs. Anything greater than a PM-F0 (as machined) finish requires some level of hand work, up to an SPI-A2 mirror finish using Grade #2 diamond buff. Avoid fine finishes such as these unless they’re required for the job. One thing to consider regarding cosmetics is to let Protolabs know if you need the entire half of the mold polished or maybe just one small area. You could save costs by only polishing the area needed versus the entire side of a mold. When requesting a custom finish, just send Protolabs a color-coded image of the critical areas and desired finish level for each area.

Get machined parts anodized and chromate plated with our quick-turn finishing option. Eligible materials include aluminum 6061/6082 and 7075.

J-CAD has a long-standing positive experience of close to a decade in foam injection molding. All of our products are of superior quality. Our experience coupled with recent technological improvements has enabled us to develop our own advanced structural foam injection molding system that produces products of ultra high quality.

It is relatively easy to remove metal from an existing metal mold. Adding metal, on the other hand, can be difficult or, for all practical purposes, impossible with rapid injection molding. To look at this from the part perspective, you can add plastic, but you can’t take it away. Designing with this in mind is called “metal safe.”

Undercut features complicate and, in some cases, prevent part ejection. Get rid of them if you can, but maybe that’s not possible, if, for example, you need a side action, sliding shutoff or pick out. One alternative may be using sliding shutoffs and pass-through cores, or by changing the parting line and draft angles to provide an easier mold build. These reduce tooling costs as you avoid additional pieces to the mold that add to manufacturing costs. In addition to the rise in manufacturing costs of using hand-loaded inserts, this also may have an impact on your piece part price because of longer cycle times and manual mold operation.

If you haven’t noticed, it is highly unlikely that a day comes by without you seeing some sort of polymer foam, they are being used everywhere with an incredible array of applications. You may ask yourself why are they everywhere?

Maybe you are after a higher volume of parts? You can still achieve high volumes using aluminum tooling with two-, four-, or eight-cavity molds depending on size and part geometry that can reduce your piece part price, although this would impact your tooling costs.

The foam made from it is closed-cell and waterproof, its cells are tightly connected, giving the CFAs are typically used when trying to achieve higher density foams and they can improve the quality of the final product immensely. They are often used for the production of strong, yet lightweight structural foam moldings. As well as the extra strength, — depending on the shape of the mold – CFAs will also save you money, since thicker walls make it easier for the foam to form. You can generally expect a reduction of 10 to 25% of the weight, or even more with a well-formed design.

Low-pressure structural foam molding is very similar to the conventional injection molding process, with a much lower pressure. In most instances of low pressure molding, the molten polymer is injected with nitrogen gas, a chemical blowing agent or an inert gas (NI, CO2, CBA…). The mold won’t be completely filled with the resin as with high-pressure molding, the injected gases are mixed with the polymer, and then they are allowed to expand inside the mold.

The process starts with the gas/polymer mixture being short-shot injected through nozzles directly into the mold. The blowing agent then expands and pushes the molten resin into the cavities, thus reducing sink holes over heavy cross-sections. This approach to manufacturing gives the product a cellular core surrounded by a rigid and dense outer skin, building structurally sound products while reducing their weight and density because of the development of the structural core. Keep reading

Polystyrene is a synthetic compound, that can be solid or foamed. It is made from monomer styrene and is considered and aromatic polymer. It is one of the best materials that could possibly be used for foam injection molding.

When working with lower pressure, there’s the benefit of being able to use more economical molding equipment, for this reason, it is cheaper to do mass production of larger, thicker parts by structural molding, than conventional injection molding. And you can expect the finished part to be typically 10 to 30% under the weight of an equivalent conventional injection molded part.

1. Eliminate undercuts 2. Get rid of unnecessary features 3. Use a core cavity approach 4. Reduce cosmetic finishes and appearances 5. Design self-mating parts 6. Modify and reuse molds 7. Pay attention to DFM analysis 8. Use a multi-cavity or family mold9. Choose on-demand production option10. Consider part size11. Use overmolding

You can add CFAs to the injection molding machine just as if they were colorants or additives. CFAs can also allow for an increase in shot speeds and can reduce clamp tonnage, achieving a reduction that can be as high as 30% in cycle and production times. Pretty amazing benefits from using just one simple additive!

The visual above is just the basic principle of the foam injection molding process. The quality of the end product is highly dependent on how delicately the foam injection process is balanced which we have mastered at J-CAD Inc. We have done away with stop-and-flow molding because of the resulting inconsistency in gas dosing. We have come up with ways to ensure that there is continuous flow of both the blowing agent and polymer during the injection process. We have also introduced a lot more modifications to ensure that the end products are of superior quality and the cost of our products are affordable.

While injection molding may seem costly compared to processes like CNC machining and 3D printing, the ability to scale and manufacture thousands of parts makes it a cost-effective solution for mass production. Determining the cost of injection molding is a combination of several factors. The main determinant of molding cost is the amount of time it takes to produce the tooling. This means, the more complex the part's geometry, the higher your manufacturing costs will be. Simple parts, without undercuts or more advanced surface finishes, will be the most affordable.

Aesthetically Pleasing EVA Foam develops a perfect mold finish upon completion, the process creates parts with great aesthetics, and the quality is always consistent. And even though EVA Foam products are more expensive than other types of foam production, the result is always an attractive product with long-lasting value which is less likely to deteriorate over time.

This type of resin can also be colored with a variety of additives and is very resistant to most chemicals. This allows products to be suitable for lots of uses. Keep reading

In addition to per-unit costs, consider the material. Many plastics overlap in strength and functionality, but some are inherently easier to mold, driving down part costs. You can experiment with different materials in the interactive quote you receive when you upload your design to Protolabs.

Got a family of parts that all fit together? How about multiple molding projects at one time? There’s no reason to build a mold for each individual part, provided A) everything is made of the same plastic, B) each part is roughly the same size (e.g., have similar processing times), and C) can all be squeezed into the same cavity, while still allowing for proper mold functioning.

Structural molding shares some similarities with injection molding, but these are the main differences between the two processes:

Our equipment have been customized to ensure utmost efficiency and cost effectiveness while maintaining superior quality. Our pumps can handle a highly controlled flow rate of a very wide range. They also handle a wide pressure range that is highly regulated.

In addition, maybe you can join some of those parts with a living hinge? This method is a great way, for example, to mold two halves of a clamshell-style container. These parts would otherwise need a pin-type assembly to open and close. The only caveat here is that a flexible and tough material must be used, such as polypropylene (PP).

Always consider part extents. In molding-speak, that means how big is the part, and will it fit comfortably in the mold while allowing for sprues, runners, ejector pins, and all the other considerations needed to make a mold work. Protolabs’ maximum part size for injection molding is currently 18.9 in. (480mm) by 29.6 in. (751mm) with a maximum depth from the parting line of 4 in. (101mm) deep. However, larger parts like these, in turn, require a larger mold. This may have an impact on your mold and part costs.

Finally, consider an overmolding option. Depending on the part, it might cost you more upfront, but could potentially save you money later. For example, overmolding a gasket on a part upfront might be an added cost, but it can save costs later from having someone install a gasket manually.

There are many kinds of CFAs, since they can be organic or inorganic compounds. CFAs generate exothermic or endothermic reactions, and they are used in this process to nucleate the foam structure that results from the expansion of the gas that is injected to the mold, as it decomposes while dispersing through the polymer melt. Keep reading

Some injection-molded parts go through multiple iterations until a final, workable design emerges. Instead of purchasing a new mold for every revision, a little clever planning will allow the same mold to be used multiple times. Starting with the smallest, most basic part design, mold as many pieces as needed, then re-machine the mold to include additional part features, or a larger, taller version of the same part, and mold again. This is not an exact science, but given the right part, this re-use approach can save dollars on tooling development.

Polyurethane is a polymer that is available in thermosetting (does not melt when heated) and thermoplastic (melts when heated) versions.

One important feature of CFAs is their ability to be processed on all injection molding machines, if you know what you are doing. In order to obtain a uniform foam structure, the CFAs injection rate requires special attention.

Proto Labs, Inc. 5540 Pioneer Creek Dr. Maple Plain, MN 55359 United States P: 877-479-3680 F: 763-479-2679 E: [email protected]

High-Quality Dimensioning With EVA Foam molding the process can be closely controlled, so you can expect to produce really consistent dimensional parts. The manufacturing of the foam and the final product are the same, they happen at the same time. Because of the simple controlling of the process, there is minimal part-to-part variation.

EVA, or ethylene-vinyl acetate foam is a soft and durable polymer processed as a thermoplastic material, commonly used in flooring and sports equipment due to it being highly cushioning and sponge-like.

Thickness variation EVA Foam injection molded parts can be made to any height or width, they aren’t limited by the process. There’s no need for lamination.

Also known as polyethene, polyethylene is the most commonly found plastic around the globe, with annual production being around 80 million tonnes.

Our helpful design aid demonstrates part features that are too thin or too thick, bad bosses, right and wrong ribs, and other considerations to be mindful of while designing parts for injection molding.

Maybe you’re designing a snap-together case for some medical components, or two interlocking halves of a portable radio. Why build two mating parts when you can make one? Redesign the snaps so that the halves can be fit together from either direction, thus building a so-called “universal” part. Only one mold is needed, saving production expenses up front. And you can now mold twice as many of one part, instead of half the quantities of two.

EVA foam is non-toxic and easy to work with. It has some of the properties of a low-density polyethylene with increased gloss, softness and flexibility. It’s also weather resilient; with resistance to UV radiation, low temperatures, good impermeability and high stress-crack resistance. There are both filled and unfilled EVA products. Keep reading

If you don’t feel foam is right for your product (ask us to clarify if you’re not sure) we also have much experience in silicone and plastic injection molding.

Every quote for an injection-molded part at Protolabs is accompanied by a free design for manufacturability (DFM) analysis. This identifies potential problem areas, or opportunities for design improvement. Insufficient draft angles, “un-machinable” features, impossible geometries—these are just a few examples in which part designs can and should be improved before clicking the “accept” button. Be sure to review these suggestions thoroughly, and contact an applications engineer at Protolabs with any design-related questions.

Our digital factories create prototypes and low-volume parts fast, while our manufacturing network, offers advanced capabilities and volume pricing.

In Foam injection molding, thermoplastic materials are first melted. When the melted plastic is evenly soft, an inert gas (blowing agent) is introduced into the polymer melt to make the solution foam-able. The solution is then injected into a mold to make the foam product.

Polyurethane foams are made by mixing two-part polyurethanes, that expand upon mixing and fill the molds, allowing for a lot of variety in material density and functionality. It’s important to stabilize both polyurethanes to a certain temperature; if when mixing the temperature is too hot the foam will be too light and weak, if the temperature is too cold the foam becomes too dense.

When doing foam injection molding there are several ways of modifying a material’s properties. In most instances what you are looking for is weight reduction and sink removal on your parts, and one of the main ways of solving that is the usage of Chemical Foaming Agents (CFAs).

At J-CAD Inc. we produce a very wide variety of products owing to our diverse customer backgrounds and industries served. Our products include:

Flexible polyurethane foams are easy to use and durable, and very efficient for absorbing energy at controlled rates, changing resonance or shock-pulse frequencies and relieving static stress on flexible materials. Some foams are also great at handling really high temperatures, with some avoiding long-term effects up to 180°F.

Direct injection expanded foam molding is also known as injection molded foam, and it’s used to create soft foam products from a complex base resin made from an ethylene and polyolefin elastomer. They become very rigid, but are really easy to use and cure, and can be used as a lightweight casting or filling material.

Still another way to reduce molding costs, depending on your part volumes, is to consider on-demand manufacturing. At Protolabs, two injection molding service options are available (see table below). One is best suited for those who need smaller part quantities, usually associated with prototyping. The other option, Protolabs calls it on-demand manufacturing, is a good fit for those who require slightly larger part quantities, typically up to 10,000-plus parts from aluminum molds. On-demand production can be a great option to manage demand volatility of your parts, reduce total cost of ownership, and leverage cost-efficient bridge tooling.

can work well as long as they are sealed and a silicone release agent is used on them prior to molding. Another plus with molding in flexible foam is the ability to add color pigments to achieve vibrant colors.

However, maybe your molding project calls for only a handful of parts. No worries. Protolabs builds cost-effective molds for production quantities as low as 25 pieces, often within a few days of ordering.