Injection Molding VS 3D Printing
Both 3D printing and injection molding are the manufacturing technique to produce plastic parts and products. Each technique has its own advantages. At TEAM Rapid, we can use both 3D printing and injection molding together as complementary manufacturing methods.
3D printing technology is an additive process which creates parts by building up materials layer by layer. Plastic injection molding uses a mold which is filled with molten material which cools and harden to creates parts.
Both injection molding and 3D printing can be used for prototyping. Below are some differences between these processes.
What is the different between injection molding and 3D printing?
1, Injection molding is better for produce high volume. Injection molding create minimal material wastage.
2, 3D printing is a slower manufacturing process. The set up for 3D printing is faster. 3D printing allows frequent design change. It is better for complex design.
What is 3D printing?
3D printing is also known as additive manufacturing. Turnaround time for 3D printing is fast which is around one to two weeks. It is ideal for rapid prototyping and design with frequent changes. 3D printing allows to produce small plastic parts. It’s ideal for complex and intricate design. It is best suited for low volume production run of 100 units or even fewer. If using 3D printing for high volume production, it is costly for time and money.
Advantages of 3D printing
1. Lower set-up cost
Compared to injection molding equipment, a desktop 3D printer and 3D printing materials are cheaper. Open-source software and hardware can offer ongoing support which may be free of charge or at little cost.
2.Allow design changes
3D printing, as an additive process, it allows to make design changes even during production. It will save time and money on a run of parts which may have mistakes. It you want to change the design; you don’t need to start the whole production run from the beginning. 3D printing is also an ideal process to build quick prototypes as the set-up charge ahead of production is low.
3.Good for complex design
As 3D printing creates parts layer by layers. 3D printing is good for producing complex design with detailed infrastructures.
Disadvantages of 3D printing
1, 3D printing is a slow production method. The number of parts being produced at a time is limited by the The CAD-based, detail oriented process. Most 3D printers can only build one or two parts at a time.
2, 3D printing can not produce larger parts because 3D printing process is limited by the size of the printing area. If the parts hang off the edge of the printing, the design is unstable.
3, Rough finish. As the layers are additively built, the finish of 3D printing part is rough. So, if you want a smooth finish, post-process is required.
What is injection molding?
Injection molding has a long turnaround time which is around five to seven weeks, so it is not suitable for projects with frequent design changes. Except for the long turnaround time, injection molding process is suitable for high volume production. The injection mold is fine for both small and large parts with complexity.
Advantages of injection molding
1.Injection molding process is able to produce parts in high volume. Injection molding use a high number of molds at a time so it is more cost-effective to produce parts in a large number.
2.Injection molding enhance strength of parts. Injection molding produce part by poured material, it eliminates fissure and weakness. Injection molding works for dense material like concrete which need to be diluted or revised for 3D printing.
3.Injection molding creates less wastage. As the material is poured into a mold during injection molding process, it uses the exact amount of material needed for the design. So, this manufacturing process is ideal for producing parts in high volume cost-effectively.
Disadvantage of injection molding
1, Injection molding process has design limitations. If you want to remove an object from the mold, it is very difficult because of the right angles in the design unless you break the mold. Injection molding is not suitable to build precise and delicate designs.
2, As injection molding needs long set-up time, it is costly and difficult to revise the mistakes in the design. The mold may have to be remade completely to fix problems or change design.
3, Injection molding machines are expensive. The cost of building molds, materials and design prototyping should be taken account of.
Application of injection molding and 3D printing
Injection molding is suitable for:
1, High volume production as multiple identical objects simultaneously.
2, Solid design which are based on continuous form
3, Parts with smooth finish. It reduced fabrication compared to rough finish of 3D printing parts.
3D printing is suitable for:
1, Low volume production which include prototypes.
2, Complex design with gaps or holes in the middle
3, Frequent design change and even in production
Can 3D printing replace injection molding?
3D printing and injection molding are treated as competing technologies, but each of them has their own advantages and suitable uses.
In recent year, 3D printing is becoming more and more widely used. Injection molding is still used for producing plastic parts for industry. Because costs and quality are controlled when also allowing for high volume production.
As injection molding tool design is cost and time consuming, 3D printing is a better process for prototyping compared to injection molding process. For example, in the medical industry, 3D printing has been embraced for creation of custom part like artificial heart valves, dental products or prosthetics and more.
Instead of saying 3D printing is a potential replacement for injection molding, both 3D printing and injection molding can be as complementary process which could be used together depending on project requirement. It makes it possible to shorten production cycles before running in to mass production by using them together.
Conclusion
Both 3D printing and injection have their own advantages and disadvantages as they should be treated as complementary instead of competing process. They both helpful processes in their own right. 3D printing is ideal for low volume, complex parts which need frequent design change. It gives engineers the power to create designs at their desks and bring their ideal to life in a matter of hours. Injection molding is better for quickly and reliably high-volume production of less complex parts which have no design change during production. At TEAM Rapid, we offer rapid manufacturing with all aspects related injection molding and 3D printing. If you want to learn more about our services and support, contact us today.