CNC Machined Metal Parts Vs. Injection Molding: Which Should You Choose?

If you are a manufacturer who wants to create a prototype for a new project, there are different production methods you have at your disposal. Depending upon the volume, precision, and speed of the production, you have the option to choose between CNC machined metal parts and injection Molding, two of the most popular options among manufacturers.

It is important to understand these processing methods before you commit to them. As for different products, one might be preferred over the other. Both of these processes are used to produce plastic parts for everyday products like toothbrushes, medical equipment, toys, etc.

What is Injection Molding?

Injection molding is one way to manufacture parts. During the production, thermoplastic is injected into a strong mold, and then with pressure and heat, that injected plastic turns into the shape of the molds. Small granular plastic pieces are firstly heated at a high temperature to create a liquid state of that plastic. That liquid plastic is known as thermoplastic, which is used in production.


What is CNC?

CNC is a subtractive process that is unlike injection molding. CNC, which stands for Computer Numerical Control, is a process of cutting down from a solid block with the help of computer programming. These computers can measure precisely on 3 to 5 axes. In this process, a solid block of material is pushed through into the machine; the computer then takes information from a digital file like CAD and turns that into commands for the machine to precisely cut one layer at a time to get the desired machined metal parts.


CNC Machined Metal Parts Vs. Injection Molding

  • MOQ:

Injection molding requires a lot larger initial investment, so if you are doing a small volume, the price per unit won’t be more financially feasible than the CNC machined metal parts. But as the machines and molds are very durable, unit cost becomes a lot more reasonable for a large volume.

  • Prototype:

It is easier to do a prototype on CNC as you can create a solid block and then use the design to make a prototype instead of making a mold. The process is a lot faster, and even if it isn’t up to the mark, wastage is a lot less with CNC. In addition, if you cooperate with a trustful CNC prototype supplier, you can even cut a large part of the cost and time.

  • Design Freedom:

You have a lot more prototype design freedom with injection molding than with CNC, as it is hard to achieve very sharp corners with CNC. But if your design has the probability of changing in the future, CNC machined metal parts are better as it would be hard to change the mold once produced.

  • Quality:

You can achieve high-quality products with both, but all in all, CNC machined metal part is born for preciseness. If you are looking for high volume, injection molding is the easier of the two to repeat the process.

  • Lead Time:

Injection molding lead time is much higher as you have to create the mold before starting production.  Also, the overall setup requires a much longer time and a bigger budget.

  • Alteration:

It is much easier to alter the design later with CNC machined metal parts as you will only need to change the design file but in injection molding, you will have to alter the mold.

  • Strength:

Strength depends largely on the materials of the product. CNC usually adopts metal as the processed material, which is hard enough for the parts. However, the strength of injection molding is not as controllable or measurable as CNC machined metal parts. Some other materials, like plastic or glass, are also included, giving you more options.

  • Surface finish:

Injection molding forcibly removes all the cooled parts from the surface, leading to a bit of imperfection on the surface. So, CNC machined metal parts are preferred if you need a perfect surface-level finish.

Where to Find the Best CNC Machined Metal Parts Supplier?

Suppose you are looking for material parts or want to create rapid prototyping, and the supplier you can trust is AS PRECISION, which offers an amazing range of options. Our CNC rapid prototyping methods are what you need if you want to create a prototype within a small budget and on a tight timeline.

For high-quality machined metal parts, amazing finishes, and the option to alter before going into major production, AS PRECISION is what you are looking for. We have years of experience and know exactly how to cater to your needs perfectly. Regardless of you being equipment, vehicle, electric, or some other type of company, you just can’t go wrong with us.