Why is prototyping important step in design process

prototyping engineeringPrototyping is a physical simulation of a system or product when product design or development stage, which help engineering people or investors to evaluate their design. It’s commonly used to identify and rework the desired product until the final system is sealed. A successful prototype will avoid your design fault, make your manufacturing cost down, and reduce your project risk. Since it’s so necessary and important to us, we would like to discuss its advantage in details as below:


Design Validation

When you start with a new product design, you will not be able to confirm if your design works or not until the final product is ready. But prototype can play the role of foreseeing any project risk, like conceptual feasibility, functional, and structural details. In this way, you don’t need to wait for real molded parts to evaluate your design. Otherwise you might loose lots of money to prepare unnecessary components or parts.


Design Optimization


After the prototype is ready, you may have the change to evaluate your system or product very quickly, and you should always write down and design defects or faulty that should be fixed or amended that can be reviewed and followed up again when next round of prototype or real components. It help engineering people better identify any potential risk and get it resolved.


Saving cost for mold modification


On opposite, if you don’t prepare the prototype and move your design directly forward to mold making stage, it must get a big risk of possibility that your molded parts would not meet your design requirement, even your design is terrific worse. Then you have spend lots of money to get the molded parts modified. This is what I have to emphasize the importance of prototyping. I think most of big companies would follow this procedure, but for some small business runner, they may not do it right.


Show your product quickest to customers


While you are eager to attend a custom meeting or sales show, and your product development is not finalized. You can get a prototype to show your customers. This time, you might collect valuable feedback from your clients or market. By taking those advise, you can optimize your design quickly and easily.


File patents earliest


To protect your intellectual property, you might have to apply for a patent application so that others may not dare to copy your projects. It should be prepared prior to your product is launched to the market. At this time, you can take your prototype to apply for this action. So that you will keep your product always unique in the market.

a product is new enough or unique enough, patents need to be considered. It’s no use to design and manufacture a great product only to have another company start producing a remarkably similar product because the original company failed to patent key aspects of the design. On the reverse side, prototype is also a useful measure to check whether or not your design conflicts others or other companies’ patent, then look into how those conflicts can be overcome prior to mass production

All in one works, prototype is a critical engineering action when product development and manufacturing, it saves your time and cost if you do it right. Otherwise you have to pay for your faults for modifying plastic mold, injection molded parts, and other components. If you still have question or problem on prototype, you would please contact Inno Molding company, we are always here for help.



Plastic Injection Molding Process

Picture of injeciton molding processAs we know, plastic injection molding is the most common manufacturing process to obtain plastic parts. It’s widely used for various kind of products like automotive, medical, industrial, electronics and other related fields. Since injection molding is so important to us, we would like to discuss how the actual injection molding is.


Basically the injection molding requires a serial of facility including injection molding machine, mold tooling, and raw plastic material. While raw plastic material is melted in the injection molding machine, so as to be filled into the mold tooling, where the plastic parts come out. Here below are some key elements of injection molding process.

1. Mold tooling  

Prior to the injection molding process, you must prepare the relativemold tooling, where the molded part will be filled and come out. It normally takes about 15~45 days to build a plastic mold tooling as the custom mold tooling is very complicated and requires a systematic fabrication period. To build a accurate mold tooling, you should have both good mold design and mold manufacturing process. Each process should be completed by sophisticated mold designer and mold makers. Moreover choosing a high quality mold steel is also another key point that determines the mold tooling quality. The better steel, the longer use time the mold would be. Finally number of cavity will affects the cycle time of injection molding, as well the molding cost.

2. Mold Clamping

It’s a preparation job to get mold tooling clamped onto the injection molding machine. As we know, a mold tooling is mainly consist of two half(cavity side and core side), these two sides must be separately and securely fastened on the injection machine. So that each half can move accordingly when the machine is move to open and close. The hydraulically clamping pushes the mold cavity and core forth and back, and gives sufficient clamping force to keep the mold securely closed while the raw material is injected. But different mold size requires different clamping force, for surely, the larger tonnage of injection machine runs larger clamping force.

3. Material filling

The material filling of injection molding is a core process that the injection machine give force to push molted material through machine to reach mold cavity. We also call this process injection molding. Before the injection process, we should prepare the pre-heated raw material onto injection machine, during this process, the molten plastic material is then injected into the mold cavity very quickly under high injection pressure. And those injected material will stay in the mold to become the idea shape. This process is referred to shot or injection cycle. For most of plastic products, the injection cycle time takes 20 seconds~2 minutes.  The cycle time can be calculated based on the shot volume, injection pressure, and cooling time.

4. Cooling Time

After the molten plastic material is shot onto the mold tooling, the cooling system(usually by water or oil) of mold tooling will cool down the mold temperature instantly. So as to solidify the final molded parts. The tooling time normally takes few seconds or longer, it depends on material type and cooling structure of the mold tooling. During this stage, some of plastic defects might occur, like shrinkage, deformation, or venting marks. So we should consider and prevent these problem when mold design. In case these problem happens, we can also troubleshoot them by adjusting the injection parameter.

5. Ejection

After the desired parts is solidified on the mold tooling, we should have a automatic structure to take off the parts. Normally the mold tooling will be designed for ejection pin or ejection plate that push the molded parts out of the mold tooling. After the plastic parts ejected to drop off, the mold tooling will be clamped to close for next cycle of injection molding process.


After reading our article above, I think you must have some basic knowledge on plastic injection molding process. Once you still have some question, or any plastic project to run, please don’t hesitate to contact Inno Molding team for help, we will always here to help.


Injection Mold Manufacturing Process

injection mold manufacturing process pictureIf you are a product designer or plastic industry related business person, you should have some basic knowledge on how a plastic injection mold is manufactured, which will help you better know your project status, easier control your product quality, even better for engineering communication.
Injection mold is widely used to make plastic parts in the world, but its technology is still a little bit complicated for most of us. Here below we would like to share some main process of mold making technology.

Stage One : Mold design

A good mold starts from a good mold design, it determined mold structure, quality, and lifetime. Therefore mold design is very important for any mold manufacturing. Most of mold manufacturer accumulated few mold designers who have rich experience in mold design and mold making, otherwise it could be a potential risk for their company.

Normally it takes 3~5 days to completed a full mold design including 3D, 2D, and EDM process drawing. These drawings should be reviewed and approved by clients, so they would know how the mold would be. As well the clients would give comments and requirement towards those drawing.

StageTwo : Mold material and standard accessories preparation

After mold design is finalized, we must prepare all of material and accessories so as for mold making.To obtain short time of mold manufacturing, any of mold manufacturer outsource the mold material and standard accessories from professional suppliers. Like mold base, mold material, hot runner, injection pin, nut, etc.

Those mold material and accessories have different standard, for example, in China, we use Chinese local mold accessories supplier’s product named “LKM”, in Europe and US, they might use Hasco, DME, HEB,STRACK, and OPITZ standards.

StageThree :Mold core and custom accessories manufacturing

1.CNC rough machining

This process is to remove the most of additional material to obtain a desired profile or shape, so that these workpiece can be accurately machined by other manufacturing process. Rough machining process can shorten the time of other process. Normally the rough machining process will only leave 0.2~0.3mm remaining material, just like a shell on the ideal shape

2. Heat treatment for steel
As soon as the rough machining process is done, we must send those workpiece for heat treatment that will remove the internal stress which resulted during machining, On the other hand, the purpose of heat treatment is also to get certain hardness and internal balance, we can also call it hardening process. For a certain number of hardness, it depends on customer’s requirement and the lifetime of mold.
3. precision machining

When we get back the workpiece from heat treatment supplier, it’s time to machine the mold accessories in accurate geometry, since it has precision requirement and harder steel, the manufacturing process is much slower than tough machining process,  

These process could be completed by CNC, EDM, Wire cutting, or metal graving machine. It’s also a time and energy costly process. All of piece must be well-achieved, otherwise there would be some trouble for next manufacturing or injection molding.

Stage Four : Mold assembly and mold trial

After all of mold components or accessories prepared, the mold maker should collects them in a particular area so as to move forward to mold assembly process.

Mold assembly takes 1~2 hours to complete, in this stage, all the components should be correctly assembled and fitted together. Otherwise it’s easy to result in some molding defects like flash, unfull-filling, or bubbles.

If everything is successfully done, we can be happy to expect for a mold trial. Most of time, there will be some defects happens during our first mold trial.(T0), but it doesn’t matter, we can fix those defects after the mold trial.


Stage Five : Texture and job sign off

After the mold is tested and tweaked successfully, we can send the mold for texturing or logo marks. As well as some package accessories should be added outside of the mold. Then we can say good luck, we will sign off the mold to clients.

How to make a mold for plastic parts

injection mold pictureNowadays plastic parts is widely used for nearly every products. Whatever for automotive, medical, airplane, electronics, and industrial. And most of people working in plastic industrial know the mold making technology. But somehow some engineering people are still not so clear on how to make a mold for plastic parts. Thus we would like to share some experience to help people better understand this technology and choose right mold manufacturer when product development process.

Define the parts function

After a product design completed his/her design job for a certain product, he/she must have a clear definition about the part function. General to say, plastic parts act as shell, housing, frame, joint, and movement transfer. These function should be identified by mold manufacturers. So that they will know how they should make the plastic parts properly based on budget and quality requirement.

Outline your budget

As we know, in today’s business market, price competition is becoming more and more sharp. This competition come up from manufacturing originally. So we must set up a competitive budget towards to your products prior to product development. Then you can split the budget into each parts or component, so you can control the budget by yourself.

Determine the parts quality

Based on your budget and parts function, you will be able to appropriately determine what level of the parts should be. Since the parts quality will affect the parts cost. For instance, when you design a precision plastic parts, product designer usually put a tight tolerance on their design drawing which requires the parts to be made accurate within the tolerance so as to meet their function. At opposite, if the parts require less accurate, you only need to specify a big tolerance zone to make the manufacturing cost cheaper.

Parts material and forecasting(quantity)

When you complete your product design, you should know what kind of material and what the manufacturing quantity of plastic products you’ll be producing. Since the part material and manufacturing quantity will determine the type of manufacturing process you will use, and what level of the manufacturer you will choose. Certainly the plastic mold manufacturer prefer to produce the higher production(injection molding) volume when they take over project from clients. If your molded parts order is larger, you can choose the large scale of manufacturer. If medium or less order quantity, you should always find a medium and small size molding manufacturers to work with. Otherwise you would lose your bargain advantage or would be difficult to control your supplier chain in future.

Finally after you reading through our sharing above, You should have a overall view on how to make a mold for your plastic parts. Just think over every step carefully and make your manufacturing quality and cost efficiently. In case you still have problem on it, please don’t hesitate to contact us for you. Inno Molding team will be always here for you.

Inspection of injection molded parts


When you start with injection molding project or develop a new product, it’s necessary to know some common inspection method, so that you can control the product quality by yourself.

Product inspection is a wide definition of full quality check including cosmetic, dimensional, and functional identity. And we would like to share our knowledge and experience about it below.


Firstly, when we talk about cosmetic of a injection molded parts, it normally means some visual defects which can be identified with eyes, for example, deformation, flash, sink marks, welding line, flow marks, and unfilled section. Before mass production of injection molding, these defects much be fixed or sorted out by QC and workshop technicians.


Secondly, we would like to talk dimensional inspection( also called dimension measurement), which is people use some measurement tools to check the dimension of parts. The main measuring tool can be introduced in the following.




CMM(coordinate measuring machine) is a very worldwide famous measuring machine to check 3D dimensions without damaging the target part. This tool is much convenient than any other measuring tools. CMM can measure distance, geometry, and tolerance deviation. like concentricity, perpendicularity, runout, parallelism. Normally CMM can reach a measuring accuracy of 0.01mm for distance and 0.002 for tolerance deviation.



Projector is an useful 2D dimension inspection tool. It’s made from optics with lights inflection. You can use it to check short 2D distance and geometry profile. In principle, the projector magnifies the profile of the workpiece, and displays this on a visual screen. And you can see the workpiece with 1:1 scale, On this screen there is typically a grid and a 360 rotated compass, so that the X-Y axis of the screen can be aligned with workpiece to measure. Project is not quite accurate measuring tool, because the test result is affected by many different elements. The accuracy of project is around 0.01~0.03mm





Caliper is a quicker and convenient measuring tools to check distance, holes, pillars. Most of time people use caliper to have a quick check when necessary. It’s also a very basic measuring tools for QC, engineer, and technician. And accuracy of caliper is about 0.02~0.04mm as it’s a rough device  There are two different types of caliper that are mechanical caliper and digital caliper. Each of these two types of calipers has its relative merits and faults. And you should get it calibrated yearly to ensure the caliper itself is in normal condition. Otherwise the measuring data might be fault or useless.


pin gaugePin Gauge


Pin gauge is a profile tool to check space and holes. For example, you want to check the deformed workpiece by using a pin gauge. You can choose different thickness of gauge so as to find out the how much the workpiece is actually deformed. Just put the workpiece on a platform and you will easily check out the exact data. For hole checking, people normally call it go-no-go gauge. You just need plug into the hole with pin gauge, if it passed, it means the hole is at least big than the standard pin gauge. If failed, it is absolutely smaller than the pin gauge.


After you checked the cosmetic and dimensional aspects, you might have to check the function of  injection molded parts, at this moment, you will have to get it assembled with other components. When assembly, you can easily find out where the faulty is and how the mechanical property of the part is.

Finally If you still have problem with quality control or inspection of plastic parts. or you have any injection molding project to run, please don’t hesitate to contact us for help, thank you!