Tag: Plastic Injection Mold Design

Types of Plastic Molding

Types of Plastic Molding

Chances are, you’ve seen various videos on YouTube about how different everyday products are made. For a surprisingly large amount of different products, there’s some kind of molding involved in the manufacturing process. Even loaves of bread are baked in bread pans to give them a shape. And most candies – whether chocolate bars or jelly babies – are poured into molds of some sort.

Molding is a quick and convenient way to reproduce the same shape over and over while getting the same result every time. Because if this, it’s the most popular way of producing plastic parts. In the modern world, plastic is all around us. From children’s toys and kitchenware, to vehicles and medical equipment.

With the wide variety of uses plastic has, there are many things to consider during the process of designing parts. Not only will you have to choose the right polymer to ensure optimum part performance, you’ll need to know about different injection molding techniques that will ultimately shape your polymer into a usable plastic part.

How to Design a Plastic Product

Assuming you’re starting from scratch, with nothing but an idea for a plastic product you’d like to create in mind, there are a couple of things you should know about the creation of plastic products:

  • It’s good to have a design on hand for any product you want to make, but ultimately, you’ll have to get engineers and professional designers involved somewhere during the process.
  • 3D printing is a great way to help you create a cost effective prototype of any product you wish to create. Because 3D printing doesn’t require a specially designed mold, it’s easy to use this method without blowing the bank. However, 3D printing fails to be a viable long-term option for part production, as it’s not very versatile and takes much longer.
  • If you need to have a plastic mold specially designed and made in order to produce your product parts, you’re looking at a hefty sum of upfront investment. Plastic molds are very specialized pieces of precision-engineered equipment. That said, a good mold can complete 500,000-2,000,000 cycles in its lifetime, depending on what kind of mold you’re looking at.

With so many plastic products on the market, many people might not realize the sheer amount of work and dedication that goes into designing and creating these products.

With that said, let’s have a look at some of the molding processes used to create plastic parts.

Injection Molding

To explain injection molding simply, it’s the process where molten plastic is injected into a mold, then left to cool. Once the plastic has cooled, the plastic part is ejected and the process is repeated.

Plastic injection molds usually consist of two halves. Think about these halves as two halves of a hollow egg shell – when pressed tightly together, this shell with form a cavity into which the molten plastic can be poured. Obviously the mold won’t have an egg-shaped cavity unless you aren’t trying to mold egg shapes, though. The cavity will be shaped like whatever part is being produced.

Plastic injection molding is incredibly versatile, and is used to produce a large variety of differently shaped parts.

Rotational Molding

Rotational molding is mostly used to create parts that are hollow on the inside.

The process of rotational molding uses centrifugal force to form parts. During the process, liquid or powder-form resin is placed into a mold. The heated mold is then rotated, causing the resin to evenly coat the inside of the mold.

Blow Molding

Things like plastic bottles (like the ones in which soft drinks are often sold) are usually made using the blow molding process.

Like with most other forms of plastic molding, there’s a mold shape that serves as the “shell” of the shape you want to produce. But unlike with injection molding, the plastic isn’t simply injected into the mold. Instead, the plastic blown into the mold shape by filling it with air, much like when you blow up a balloon. As air is blown into the plastic, it takes the shape of the mold it’s blown into.

Compression Molding

With compression molding, the plastic is poured into a mold. Different parts of the mold then compress the plastic so that it’s literally squeezed into shape. This produces strong parts, and so the process is often used in the automotive industry.

Extrusion Molding

The basic concept behind extrusion molding is that the plastic is squeezed into a long cavity to shape it. It’s basically like if you were to squeeze cookie dough into a round, plastic pipe. You’d be left with cookie dough in a long, round cylindrical shape. If the pipe where square, you’d have cookie dough in a long, rectangular kind of shape.

This is the basic concept behind extrusion molding. And so this manufacturing process is used mostly to make long, cylinder-type shapes like pipes, for instance.

Those are just basic explanations of the main processes used to mass produce plastic parts. In some cases, a single plastic product will consist of different parts, and these different parts might be produced using different molding processes.

Best 5 Types of Plastic Molding

In today’s assembling condition, plastics are being utilized to make everything from car body parts to human body parts. Every application requires an extraordinary assembling process that can form the part in light of specifications. This article gives a short preview of the diverse sorts of trim and their points of interest and applications.

Blow Molding – Well suited for empty articles, similar to bottles

The procedure takes after the fundamental strides found in glass blowing. A parison (warmed plastic mass, by and large a tube) is swelled via air. The air pushes the plastic against the form to frame the coveted shape. Once cooled, the plastic is launched out.

The blow shaping procedure is intended to make high volume, one-piece empty articles. In the event that you have to make heaps of containers, this is the procedure for you. Blow shaping makes exceptionally uniform, thin walled holders. What’s more, it can do this economically.

Compression Molding – Well suited for bigger articles like automobile parts

The name of this trim technique says everything. A warmed plastic material is set in a warmed form and is then compacted into shape. The plastic can be in mass however regularly comes in sheets. The warming procedure, called curing, insures the final part will maintain its integrity. Similarly as with other molding techniques, once the part has been formed, it is then expelled from the mold. In the event that sheeting plastic material is utilized, the material is initially trimmed in the shape before the part is evacuated.

This strategy for molding is extremely appropriate to high-quality mixes like thermosetting gums and also fiberglass and fortified plastics. The predominant quality properties of the materials utilized as a part of pressure embellishment make it a precious procedure for the car business.

Expulsion Molding – Well suited for long empty framed applications like tubing, pipes and straws

While other forms of molding uses extrusion to get the plastic resins into a mold, this process extrudes the melted plastic directly into a die. The die shape, not a mold, determines the shape of the final product. The extruded “tubing” is cooled and can be cut or rolled for shipment.

Injection molding – Well suited for amazing, high-volume part fabricating

Injection molding is by a wide margin the most flexible of all Injection molding procedures. The presses utilized as a part of this procedure change in size and are appraised in light of weight or tonnage. Bigger machines can Injection mold auto parts. Littler machines can deliver exceptionally exact plastic parts for surgical applications. Likewise, there are many sorts of plastic pitches and added substances that can be utilized as a part of the infusion forming process, expanding its adaptability for originators and designers.

The process itself is fairly straightforward; however, there are many enhancements and customization techniques that can be used to produce the desired finish and structure. Injection molds, which are usually made from steel, contain cavities that will form the parts. Melted plastic is injected into the mold, filling the cavities. The mold is cooled, and the parts are ejected by pins. This process is similar to a jello mold which is filled then cooled to create the final product.

Custom Plastic Injection Molding

The form making costs in this strategy are moderately high; be that as it may, the cost per part is exceptionally lower. Low part cost alongside resin and finish alternatives have all added to Injection Molding ‘s ubiquity in today’s assembling scene.

Rotational Molding (Rotomolding)– Well suited for expansive, empty, one-piece parts.

This procedure utilizes high temperatures and rotational development to coat within the shape and frame the part. The steady turn of the shape makes radiating power framing even-walled items. Since it is in a perfect world suited to extensive empty compartments, for example, tanks, it is not a quick moving procedure. Be that as it may, it is an extremely sparing procedure for specific applications and can be less expensive than different sorts of embellishment. Next to no material is squandered utilizing this procedure, and abundance material can regularly be re-utilized, making it a sparing and ecologically reasonable assembling process.


Each sort of molding has its qualities and shortcomings. Designers and specialists need to comprehend these distinctions and the generation alternatives accessible. There are constantly a few ways to deal with a last assembling arrangement. The molding organization who counsels on a particular venture ought to have the capacity to give extra experiences into the applications and materials that are most appropriate to an individual venture.

How to Choose the Proper Plastic

If you’re looking to become a plastic molder, the two main things you should consider are your plastic injection molds and the materials you’ll use to create parts. Before setting out to have your mold designed and made by Quality Mold Shop, you should consider the purpose of the part you plan to create.

Choosing the Right Plastic for the Right Job

Different plastics have different properties, making some more suitable for certain jobs than others. If you take a look around you, noticing different things made from plastic, you’ll notice how similar plastics are always used to make similar products.

Your laptop case, for instance, will always be made from a hard plastic rather than a soft one. If you examine the properties of the plastic used to make laptop cases, you’ll notice that the plastic doesn’t really give way or bend easily. It’s hard, yet it’s durable enough to not break or crack easily if it gets a light knock. The lid on your lunch box, on the other hand, isn’t hard like that. It’s a soft plastic that easily bends and gives way. This can help it to stretch a little over the lunch box container, creating a stronger seal.

If you used a hard plastic to make a lunch box lid, it wouldn’t stay on the container as securely. And if you used a soft, bendable plastic to make a laptop case, it wouldn’t protect the hardware inside the computer from light knocks.

In both cases the plastic used was picked carefully based on the function of the part that’s being made. This is what makes plastic such a popular material for manufacturing, its versatile. But that versatility comes in the form of different polymers. After looking into plastic injection molding and different types of plastics available, you’ll see that laptop cases are most often made of plastics like ABS (acrylonitrile butadiene styrene), while lunch box lids are made from materials like polyethylene.

Practical Considerations

Of course the ultimate function of a molded plastic part will be an important consideration when choosing the right polymer for the job. But how will you know what factors to consider in order to choose a plastic with the right properties?

Here are some of the practical things to consider when choosing what material to use for your plastic parts.


Some polymers are just more expensive than others, so the market value of your final product will have a big impact on your choice of polymer. The raw material could cost you anywhere from less than a dollar per pound, to as much as $50 dollars if you need a specialty material. So obviously the possible price fluctuation is huge.

And it goes without saying that you simply can’t use a polymer that costs $50 per pound as a raw material, if your final product will requires a pound, but will only cost $40. That’s an oversimplified example, but it drives home the point that cost is vitally important when choosing what plastic to use.


Some products don’t need to be very durable at all, while other products are expected to last as long as a lifetime. You’ll know how durable you expect your product to be before having a mold made, and so you should choose a plastic that can live up to these expectations.

People don’t expect disposable plastic cutlery to be particularly durable, but a reusable plastic cup should be made of plastic that won’t easily crack like its disposable counterpart.

Another essential part of choosing a durable material is its resistance to temperature. A simple plastic like polyethylene isn’t very temperature resistant. So while it’s a good plastic for everyday objects, it won’t perform well under somewhat more extreme temperatures. While hot conditions isn’t good for the material, cold conditions also negatively affect its plasticity. Meaning that a part made from polyethylene can actually break or shatter below freezing point, losing its ability to flex.

Part Design

The shape of the part you want to make will influence the polymer you choose. Simple shapes can be made using almost any polymer, but if the part you want to mold will have more holes, depressions, ribs and gussets, you have to pick your polymer more carefully. Not all plastics can be as easily shaped as others.

And while aesthetics isn’t necessarily the most important thing to consider, it’s also something that will influence your decision. Getting a plastic with high gloss, or one that will be good for making a part with a matt effect might be important to you.


Some parts are meant to be able to bend a lot without cracking, while others are made not to bend. It goes without saying that any part that will have to flex a lot, should be made from a plastic that can handle this kind of tension without snapping and breaking. But some parts are meant to stay securely in place under pressure without flexing or giving way, and these parts should be made from harder, yet durable plastics.

The best way to know what plastics will be a good fit for your project is to talk to professionals. Follow the advice from both the engineers working to make your molds, and a chemical engineer. After all, the best way to get it right the first time is to not base your choices on guessing games, but to rely on sound professional advice.

Want to know how to source automotive plastics? Looking for a plastic molder?

How to Design the Perfect Plastic Part

Used to deliver top notch exactness parts everywhere volumes and low costs, plastic injection molding offers adaptable answers for a scope of uses.

While this procedure offers a few one of a kind advantages over other generation forms, the achievement of an injection shaped part relies on upon its mold; with the correct outline, durable, quality plastic parts can be made reliably and effectively. Poor outline can prompt to expensive and tedious preparing botches.

With a specific end goal to advance the viability of high-volume injection molding and boost the exactness and nature of your parts, a few key plan components ought to be considered before proceeding onward to creation.

Divider Thickness

You can reduce — and even eliminate — most injection molding part defects by taking the time to lay out a smart wall-thickness design. The key is to ensure that the thicknesses of all walls are as uniform as possible, as molten plastic will seek out the path of least resistance (in this scenario, larger wall areas), leaving smaller wall areas potentially unfilled.

Rib Design

Ribs are utilized to fortify the quality of a high-volume injection molded part. Ribs ought not surpass 70% of your parts divider thickness, be that as it may, nor should they fall under half of divider thickness; both situations can bring about soaking in the surface of your part. Additionally, make sure to give careful consideration to the tallness of the ribs, their area, and their level of draft for simplicity of discharge.

Boss Design

Bosses are part features serving as one component of a larger product that requires assembly. During assembly, bosses can serve as anchor locations for screws, pins, or other fasteners. These components have width and height recommendations similar to those of ribs. Pairing bosses and ribs, especially in corners, can strengthen your part and significantly reduce chances of sinking.

Corner Transitions

In high-volume plastic injection molding, parts with outrageous or unexpected geometric elements can be inclined to defects — liquid plastic streams in the easiest course of action, and brutal points can obstruct that development. At whatever point conceivable, all corners and divider creases ought to be bended, with coordinating inside and outside spans. Smooth corner moves take into consideration better plastic stream.

Weld Lines

Weld lines — otherwise called weave or merge lines — happen when two plastic streams, or two areas of a solitary stream, meet. They happen most ordinarily around gaps or different hindrances, with the plastic stream isolating to pass them and afterward returning together a short time later. Each plastic infusion formed part has weld lines: the objective is to plan your part so weld lines happen in areas that don’t trade off your part’s quality or respectability.

Gate and Vent Placement

The gate of a large-volume injection mold is the point at which molten plastic exits the mold’s runner and enters the part cavity. Both the type of gate you choose and where you choose to place it can substantially impact your part’s quality. Vents, which allow air to escape from the mold as plastic rushes in, are similarly important; when positioned properly, vents can help minimize weld lines.

Plastic Injection Molding Process

Plastic Injection Molding Process

The plastic injection molding process is adaptable, making it versatile enough to produce anything from a simple plastic cup to car and laptops parts. While there are some alternatives to injection molding – like 3D printing and spin casting – injection molding remains the most reliable way to produce plastic goods. Because of this, injection molding is still the technique most often used to produce plastic goods in the 21st century.

But what is injection molding exactly? What does the typical injection molding process look like? And what exactly is it that makes injection molding so much more adaptable (and hence more versatile) than other options?

What Is Plastic Injection Molding?

Plastic injection molding is a technique used to shape plastic in the form of the object you’re aiming to produce. During the injection molding process, thermoplastic polymers are injected into a mold cavity. To do this, pellets of a material are heated so they can be injected into the cavity in a liquid state. This hot liquid is then left to cool in the mold so the part can properly set. Once one part is ejected from the mold, another cycle can promptly begin.

Although injection molding can also be used for metals and glass, it’s a particularly popular production process for manufacturing plastic parts.

The steps in an injection molding process cycle include clamping, injection, cooling and ejection.

During clamping, the injection mold is prepared for a cycle by tightly clamping the two halves that form the mold cavity into place. This ensures that the molded part will have a smooth appearance and ideally the molded part should have almost no line where the different halves came together, as this shows that the mold might not be clamping tightly enough.

Once the mold halves are clamped together, the mold is ready to form a part. Before the polymer is injected into the mold, the pellets are heated to form a liquid. The liquid polymer is then injected into the mold through a nozzle. This is the injection stage of molding process, which is the second stage in a four stage cycle.

Next, the part is left to cool in the mold for a predetermined amount of time. The cooling stage can take anywhere from a few seconds to a few minutes depending on the polymer being used to produce a part. While some polymers need hardly any time to cool at all, others can take a few minutes. It all depends on the part being produced.

Once a part has cooled, the injection mold is opened and the part is ejected from the mold. The mold will clamp again and prepare for its next cycle.

Because manufacturers know how long the cycle on their molds are, they can accurately predict the amount of parts a mold will produce every hour. This helps manufacturers know exactly how many parts they’ll be able to produce every day, week and month with a fully functional mold.

Why Is Plastic Injection Molding So Popular?

As mentioned above, plastic injection molding is a very predictable process. This predictability also makes the process dependable, as injection molding companies will know exactly how many parts they can expect from every mold they own.

Based on the amount of parts each mold is able to produce, manufacturers can calculate how many molds they need to in order to produce enough parts for their production line to operate at its intended capacity.

It should also be possible for manufacturers to estimate the amount of parts they can produce with a mold during its entire lifetime, making it easier to calculate whether or not a mold will generate enough income to cover its own costs with profit added.

All this is fine and well, but for injection molds to be reliable and predictable they must be maintained according to a maintenance schedule.

Unfortunately, some manufacturers run their molds till they break down. This might be because they’re just inherently stingy, but often times it was recommended to them by financial advisors in their company. The problem is that finance and engineering are worlds apart.

As mold manufacturers, we know that regular mold maintenance can extend the lifetime of your molds and help them operate optimally at all times. Yes, mold maintenance is an expense, but it’s not one you can cut to save money. If molding plastic parts is an integral part of your business, the condition of your molds in undoubtedly important. Cutting on maintenance by working molds till they break down will hurt your company.

It’s ironic that predictability, which is one of the advantages of injection molding, isn’t considered by many molders when overworking their molds. Fact is, a mold that works till it breaks down can’t always be repaired, and the halt in production from the broken mold can’t be scheduled because you won’t know for certain when it will break down.

When looking at it like that, it’s hard to understand why working a mold till it breaks could be considered a viable way to save money. Perhaps it’s time that molders look further into the issue of maintenance to establish what really works best.

But apart from the predictability of plastic injection molding, the process is also very versatile. Thousands of polymers can be used for injection molding purposes, and injection molds can be adapted for different uses. Which is why the process is as effective for the automotive industry as it is for the medical industry. With micro-molding technology, injection molding can even produce even very small parts with surprising accuracy.

To conclude, injection molding is popular mainly because no other manufacturing process allows manufacturers produce a lot of parts in a relatively short amount of time, all while maintaining the desired level of part integrity.

The Life Cycle of a Plastic Injection Mold

The Life Cycle of a Plastic Injection Mold

If you’re a molder, your injection molds are one of the most important pieces of equipment you use. Because your molds are so vital to you, it goes without saying that you want them to last as long as possible. Molds are expensive to replace, so knowing more about the life expectancy of your molds can help you plan ahead financially for when a mold will need replacement. Getting a new mold made to replace one that’s at the end of its life, but still in use, can help you keep production going. That way production can keep going, and a mold that breaks down doesn’t have to slow you down.

Plastic Injection Mold Lifetime

Truth be told, determining the lifetime of a plastic injection mold is easier said than done, as many factors contribute to the life expectancy of a plastic injection mold. Plastic injection molds operate under harsh conditions, and while a good mold should be built to last under the conditions it will be operating in, even the best mold will take some wear and tear.

Generally though, the lifetime of your mold will depend on a number of factors. Molds that have a faster turnaround can finish more cycles in a day than molds with slower cycle times. Because the life expectancy of plastic injection molds is measured in cycles – as opposed to measuring mold life expectancy by considering the time a mold has been operating – molds that can complete more cycles in a shorter amount of time will generally have a somewhat shorter life expectancy.

While a shorter life expectancy might seem like a bad thing, the difference between a mold with a fast turnaround and one that’s slow isn’t necessarily that big. If both molds can complete approximately 250,000 cycles before breaking down, both are equally good. What mold owners should understand is that the lifetime of a mold is measured in cycles rather than the time a mold was operational. This makes more sense, because knowing how many parts a mold can produce in its lifetime helps molders determine whether or not a mold will be able to cover its own costs.

How Many Cycles Can a Mold Complete?

It’s impossible to know exactly how many cycles a mold will be able to complete in its lifetime. As with anything in life, there’s no way to look into the future to foresee any and all things that could possibly go wrong. Just as no one knows when a car will break down, no one can tell you what the exact life expectancy of your plastic injection molds will be.

But for the purpose of keeping better track of your molds, you’ll need an estimate. The estimation of a mold’s lifetime will help you determine whether or not a mold lived up to its estimated performance. If the estimated life expectancy of a mold was 250,000 cycles and the mold only completed 180,000 before breaking down, your mold clearly didn’t come close to its estimated 250,000 cycles. The reason for this under performance could vary. It might be that the conditions the mold was operated in led to faster wear and tear, but the problem might also be the mold itself.

To ensure that your molds complete roughly the same amount of cycles you’d expect them to, the most important thing you have to do has nothing to do with how you take care of the mold. More importantly, you should see to it that you buy your molds from an injection mold maker that can deliver quality molds. Your plastic injection mold maker isn’t just a company you buy molds from. As a molder, your mold supplier should be your trusted business partner. A good mold making company will be able to tell you exactly how to take care of your molds to keep them running for longer. Your mold making company should also be able to tell you roughly how many cycles you can expect from a mold.

The estimated amount of cycles a mold can complete will vary depending on the molds you use, as well as the quality of those molds. Generally, a plastic injection mold could complete anywhere between a 100,00 to 1 million (or sometimes somewhat more than a million) cycles in its lifetime, so it’s important to learn about the life expectancy of a mold before buying it.

Maintaining Your Molds

If you want to get the most out of every mold, you should stick to a mold maintenance plan. Without proper maintenance, even the best mold won’t complete nearly as many cycles as you’d expect it to. The company you bought your molds from should be able to help you set up a mold maintenance schedule. This helps prevent downtime, where a mold breaks down unexpectedly and all the production you were expecting from it comes to a halt.

Mold maintenance schedules will usually be determined based on the amount of cycles a mold can safely run before needing to be sent off for cleaning and other maintenance. As a molder, you might sometimes end up overworking a mold to complete orders in time, unfortunately that’s almost sure to happen at some time or another.

To avoid damaging an overworked mold you should, however, get a good estimate from your mold supplier about how much will be too much. Overworking a mold a bit before finally sending it off for maintenance might not do much harm, but overworking it too much will almost surely lead to a breakdown. Most mold suppliers will tell you not to overwork your molds at all, as they can’t really accept responsibility for damage to molds that were overdue for maintenance, but asking them how many cycles similar molds typically run before breaking down could help you get a better idea of the risks levels of overworking your molds.

Plastic Injection Molding for Automobiles

Plastic Injection Molding for Automobiles

Plastic injection mold makers have developed technologies for producing quality parts over the years. With so many thing that are made from plastic nowadays, it’s hard to believe there was a time it didn’t exits. Plastic injection molding is used a wide variety of things. Everything from children’s toys to medical equipment and household items are made using plastic injection molding techniques. What many people don’t realize is just how much plastic injection molding has developed.

Plastic Injection Molding in the Automotive Industry

In the automotive industry, plastic injection molds are used to make a surprising amount of vehicle parts. The interior of most cars are filled with plastic. The dashboard, inside door panels, ashtrays, buttons and even the carpets and bumpers are all made through plastic injection molding processes. But even when you take a look under the engine cap, you’ll see a good deal of plastic molded parts.

In recent years the use of plastic has become especially popular in the automobile industry. And this shift from using metal components to plastic is about more than just saving on production costs.

Car manufacturers constantly strive to design vehicles that are lightweight. These lightweight vehicles have been proven to be environmentally friendlier because of their lower fuel consumption. It’s been estimated that every 10% reduction in vehicle weight can lead to a 5-7% increase in fuel efficiency.

In order to make vehicles more efficient, the automotive industry is trying to revolutionize the way plastics are used in cars, aiming to make as many car parts as possible from durable, lightweight plastics. Even though an average modern car consists 50% of plastic, the plastic molded parts only account for roughly 10% of its weight, which shows how for the automotive industry has already come in using plastic improve car performance.

But the use of plastics in cars also has other benefits. By using durable plastics, car manufacturers can also avoid common problems associated with using metal, like metal fatigue and rust. The fact that plastic is lightweight, highly affordable and sometimes even more durable than metal makes it the perfect choice auto manufacturers.

The use of plastics has helped car manufacturers design and produce cars that are safer, cheaper and more eco-friendly. The best part is that these newer, more fuel efficient cars are both cheaper to buy and drive when compared to their older counterparts. Back in the day when cars still largely consisted of metal, it wasn’t as common for an average middle class family to have their own transportation.

Automotive Mold Design and Manufacturing

When it comes to molding car parts, molders need the best possible plastic injection molds to assure every part will perform well. Good molders already know how to mix polymers for maximum durability while producing parts, but there’s an essential step to producing quality parts that can’t be overlooked.

If you’re a molder, producing automobile parts your clients will be satisfied with begins with the molds you use. A good mold is one of the key things you need to run a successful plastic injection molding company. Your mold making company should be your trusted business partner who will guide you through the design, manufacturing and maintenance process every step of the way.

Keeping your molds properly maintained is necessary if you want to consistently mold durable parts for automobiles. Without proper plastic injection mold maintenance, your parts will eventually develop faulty spots and become structurally weak.

American Plastic Injection Molds for the Automotive Industry

Injection molds are expensive pieces of equipment. The mold making process requires precision engineering and manufacturing standards to create molds with tight tolerance that will serve your business for years to come. A good mold shouldn’t be a finicky piece of equipment that sporadically breaks down. After all, you can’t afford to regularly have an unscheduled halt in production of parts simply because your mold won’t function as it should.

Many plastic injection molders make the mistake of working with foreign companies that can produce molds for much cheaper. But when it comes to buying plastic injection molds, you really do get what you pay for.

If you buy a mold at a fraction of the price you’d pay in America, it’s not just because you’re buying from a country with a weaker currency. A large part of the the discount you think you’re getting is because workers producing the molds aren’t equally skilled. Companies that cater to a cheaper market aren’t set on giving you the best worth for your money in the long-term. They’re simply looking to reduce your immediate expenses, even if it ends up costing you more in maintenance and repairs in the long-run.

While the initial cost of buying a local, American-made mold might seem like a large amount to pay upfront, it’s an investment that can make or break your company. Buying a good mold from a company that will help you keep it properly maintained according to a maintenance schedule you can plan in advance (as opposed to a mold that breaks down when you need it most) will help you run your company in a way that’s within your control. A reliable mold can help you stay on top of part production and streamline your processes for maximum results.

How to Pick a Plastic Injection Molding Company

How to Pick a Plastic Injection Molding Company

Plastic injection molding is a booming industry, but picking a mold making company for your business to work with is a key factor if you want to mold high quality parts. You should choose your mold manufacturer carefully. Opting for the cheapest manufacturer can end up costing you more. If a mold manufacturer delivers a mold that doesn’t live up to your expectations, fixing it will significantly hike up its cost. Eventually, a mold you thought would be cheap may end up costing more than even the most expensive mold. The worst part is that it probably won’t ever perform at the same level.

To avoid an injection mold catastrophe, you have to pick the right manufacturer to make your mold. There are a few things to consider when partnering with an injection mold manufacturer.

American-made Molds Are Best

China is known for producing large quantities of molds that are available at reasonably low costs. But there are many reasons why an American-made mold will be best for your business. One of the advantages of choosing an American mold manufacturer is that your mold won’t have to be shipped abroad for maintenance. This not only saves you money on postage, but also means your mold won’t be away for long periods of time whenever it’s being serviced.

The other benefit of American plastic injection molds is that they’re usually of a higher quality. Although a Chinese mold maker could deliver a high quality mold, you never really know what you’re going to get until your mold arrives in America. And when your mold manufacturer is in China, sending your new mold back for repairs could take many weeks.

At Quality Mold Shop, we offer pickup and delivery services for molds weighing 12,000lbs or less, meaning you won’t have to worry about mold transportation.

Precision and Injection Mold Making

Your needs will have a huge influence on the mold manufacturer you choose. If you don’t need precision molds that are accurate to a fraction of a millimeter, then almost any manufacturer will be able to help you. But the more precision you need from your injection mold, the more you should shop around for a good manufacturer.

Ask your manufacturer about their mold making processes and the precision of their molds. For the best results, you should communicate your needs clearly to help the manufacturer understand whether or not they can deliver a mold that’ll suit your requirements.

Remember, you don’t have to go with a mold making company that can deliver precision to a fraction of a millimeter if that’s not what you need. Although this precision could indicate better manufacturing processes are used during production.

Mold Manufacturer Production Scale

Don’t just assume that large scale mold manufacturers are the best. Different injection mold manufacturers target different customers. Often times, really large scale manufacturers prefer to work with larger businesses that place large orders. If that’s the case, your order won’t necessarily be prioritized above larger ones. This could depend from one manufacturer to another, the best manufacturers will prioritize all their customers regardless of how many molds they order.

Aim for a mold manufacturer with a production scale that matches your business. You need one that can keep up, but that doesn’t have to be the largest manufacturer around.

Some people might be concerned that smaller manufacturers aren’t as good, though. But the production scale your mold manufacturer can take on isn’t an indicator of how good the molds will be. Sometimes, companies that make fewer molds can do better quality control and produce very high quality molds. The quality of molds an injection mold making company produces will depend on the expertise of the staff and machining tools, not on their production capacity.

Trustworthiness in the Production Process

You should aim to find out more about the production processes of every mold making company you’re considering to work with. Learn more about how long it takes to make a single mold and what steps every mold goes through before it’s ready for use.

Once you have a proper estimate of how long it takes to make a good mold, you’ll know if your mold isn’t delivered within a reasonable time. In that case, you can ask about what caused the delay. But remember that not all molds are the same. Some molds need much more work before they can be used than others, and if you’re working with a good company, you shouldn’t have to worry much about the production of your mold. It’s better to wait a little longer if you’ll get a higher quality mold.

Furthermore, your mold manufacturer should be trustworthy enough so you don’t have to constantly check in to see if your mold is being made properly. If possible, you should do some research to find out whether or not past customers have been satisfied with the company. You should learn more about how well the molds a company makes perform and whether or not the company will deliver as promised. A good company makes durable molds that perform well.

Experience in Mold Making

Experience is a good indicator of how reliable a plastic injection mold making company will be. At Quality Mold Shop, we have more than 40 years’ experience in producing high quality, precision molds. We also offer services to design molds as well as helping customers with injection mold maintenance plans and repairs.

Our team of experts have designed and produced molds for the automotive, medical and appliance industries. If you need a durable mold and reliable customer support, Quality Mold Shop is the ideal partner for your business to work with.

Designing for Manufacturing: Accuracy, Precision and Tolerance

Designing for Manufacturing: Accuracy, Precision and Tolerance

With design projects and CAD programming now the default apparatuses for drawing product ideas, there is the threat of trusting that anything that can be designed can simply be made. Nonetheless, while exchanging a drawing from the ideal universe of the PC to the practical universe of the machine shop, certain fundamental contemplations apply that ought to give the designer pause. Knowing how to design an item for fabrication requires the comprehension of three key ideas: Accuracy, Precision and Tolerance.


Level of adjustment to a known standard or esteem.

The standard for physical measurements is the meter, and its esteem is a widespread one in light of the separation that a light emission goes in a specific settled timeframe. Along these lines, precision is how much an estimation or development in space fits in with this known standard or one of its subordinates (regularly the millimeter or micron for metric estimations.)

In this way, when a machine apparatus is touted as being exceptionally precise, it implies that when the software engineer educates the machine to cut a bit of metal 40mm long, then the machine really does that. The more precise it is, the nearer it gets to precisely 40mm, with no blunder. There are numerous different variables required in getting precisely the 40mm cut that you’re searching for, yet simply recollect that we begin with a known esteem and exactness portrays how shut the machine gets to that esteem.


Repeatability of an estimation without producing irregular mistakes.

Precision is the capacity of our machine instruments to rehash this 40mm cut, again and again, with no presented or irregular mistake. Exact machining, or exact workmanship, is a demonstration of controlling the procedure and not going amiss – paying little respect to whatever the estimation or process might be. This is regularly mistaken for exactness and to be sure the two terms are coolly utilized to some degree reciprocally however precision alludes more to repeatability.

In our feeling of precision, it likewise applies to the performance of the task, such as taking a cautious estimation or honing a cutter head or some other occupation in a machine shop whose performance eventually impacts the nature of the completed item.


Reasonable or unsurprising deviation from a standard.

Each designer realizes that there is no such thing as ensured 100% exactness. There is just a settled upon standard. All machine instruments will have a level of free play or vibration in them – they should, or else they would be solidified, inactive pieces. The tolerance in this way indicates the deviation far from a referred to esteem, communicated as a “+/ – ” number. Along these lines, in the event that we have a machine instrument that claims a tolerance of “+/ – 1 mm”, this implies the apparatus will possibly present a deviation of one millimeter with each cut or pass. Could be an additional millimeter, or too short by a millimeter or some portion thereof.

This would be considered to a great degree poor performance, and no respectable machine instrument is that messy. Taken together, this implies exact instruments approach the standard, exact apparatuses are dependably precise again and again, and tolerances are controlled to inside a little, satisfactory level of changeability.

How does this influence Designing for Manufacturing?

As mentioned above, modern CAD programs are capable of generating 3D renders which are highly accurate, maybe too accurate. You will need to consider the following when designing your product:

  • The accuracy and precision of the tools being used to make the product. In other words, what is the capability of the factory where your product is to be made? It’s good to know this in advance.
  • The natural movement of the raw materials (metal and plastic of different types) in response to environmental conditions (temperature and humidity) and mechanical stress.
  • Necessary allowance for movement. Draft angles are applied to parts which must be removed from a tooling mold, to make space for clearance without damaging the part. Other clearances must be allowed for pieces that have mechanical fittings: screws, axles, gears, etc.
  • Kerf is the amount of material removed in the process of cutting. The computer model may not account for this lost material but the machinist must.
  • More accurate is not necessarily better. Higher degrees of accuracy and precision require more effort, time and money for diminishing returns. Pursuing extreme accuracy in one feature of a design may compromise accuracy in another area. Many part features may need some free space to allow movement or room for thermal expansion/contraction between mating pieces of an assembly.

Injection Molding Solutions For The Automotive Industry

Injection Molding Solutions For The Automotive Industry

If you’re in the automotive industry, you’ll know how important it is to produce high quality parts to create your final product. Automotive manufacturers require good molds to make various parts.

A part of automotive manufacturing that cannot be overlooked is the production of plastic parts. Plastic parts can be used for everything from simple buttons, to side panels that finish off doors on the inside and even bumpers. It’s remarkable how many plastic parts are needed to manufacture just a single vehicle.

As you’ll know, the standard process for manufacturing many automotive parts is through injection molding. Injection molding is meant to be a reliable process for manufacturing many identical parts within the shortest amount of time possible. The aim of those who make a mold, is to rapidly produce parts without having to compromise on the quality of the parts they produce.

Most molders are aware of the inherent limitations that slow down production and depending on the polymer and mold process that’s being used, cooling times can limit the amount of parts a single mold will reasonably be able to manufacture within a set amount of time. But even though there are obvious limitations on the capacity of your plastic injection molds, you should still be aiming to get the most out of them.

Like in any industry producing plastic parts, your injection molds are vital in order for you to keep manufacturing your product. But what distinguishes the automotive industry from many other industries is that the quality of plastic parts produced by automotive manufacturers is expected to be of a higher standard than many. Your final product is expected to last many years.

To produce high quality parts, you’ll need to use durable plastics that posses qualities that make them suitable for their various applications. You’ll also need to monitor the process and the quality of every part that’s produced carefully so that you can pick up problems as soon as they occur. But before you can start to work your magic, you need to see to it that your molds will be able to perform.

Bad Molds Make Bad Parts

No amount of expertise in molding can correct faulty parts if a mold isn’t functioning properly. In the automotive industry, the materials used for plastic parts tend to be expensive and a faulty mold can end up costing a company a lot of money.

There’s a good chance that your plastic injection molds are subjected to high temperatures and pressure levels on a daily basis. After all, that’s how they’re meant to work. But even though molds are technically meant to function under these conditions, they aren’t always able to do so.

For a mold to function as it supposed to, two things have to be done right.

Choose Your Mold Manufacturer Carefully

The first of step to getting a mold to function as it’s supposed to, is to adhere to high quality standards while manufacturing the mold. Plastic molds should be made with technical precision and care. A highly skilled team of qualified professionals is needed to do this.

There’s a reason why plastic molds still tend to be expensive pieces of equipment, molds are meticulously engineered to perform adequately under the conditions in which they operate. Many things have to be accounted for in both the design and construction of every mold. If the initial design and production of a mold isn’t next to flawless, it can easily break down before expected.

The lifetime of a single mold should warrant its cost, but unfortunately that won’t happen if the right process wasn’t implemented to manufacture the mold. It’s important that automotive manufactures know what the estimated lifetime will be of every mold they acquire. If you know how long a mold should ideally last, you can get an idea of the quality of molds produced by different mold manufactures by asking them about the estimated lifetime of the molds they specifically produce.

Stick To A Mold Maintenance Schedule

The second part of having molds that operate optimally is to see to it that they are regularly maintained according to a realistic maintenance schedule. Some mold owners work their molds until they break down, but that can harm the mold irreparably.

Because of the conditions molds have to operate in, wear and tear is a normal issue that will occur whenever injection molds are used. This can’t be avoided, and even the best mold money can buy will eventually need to be sent off for maintenance.

What mold owners should understand, is that parts produced with a mold will gradually be of a lower and lower quality. The last few parts produced before a mold breaks down are much more likely to be flawed than the ones that were made when the mold was still new. This can lead to an inconsistent quality from one part to the next, leading to an inconsistency in the quality of your product as a whole.

On the other hand, molds that are maintained properly will keep producing parts that you can rely on. The life expectancy of a well-maintained mold is also considerably higher. So much in the same way automotive manufacturers recommend a service plan for their vehicles, mold manufacturers highly recommend a maintenance schedule for their injection molds.

At Quality Mold Shop, we specialize in designing, manufacturing and maintaining molds. Precision equipment allows us to offer a wide range of solutions to customers in the automotive industry and we’re able to manufacture and maintain molds of almost any size or shape.