It is often jokingly said that America doesn’t manufacture anything anymore, that we import just about everything. Even though this may have been close to the truth in recent decades, more and more manufacturing jobs are coming back to the US.
With that, more people are faced with the question of which technique is suitable for the product they want to manufacture. As technology has progressed, new manufacturing methods and techniques have become available. We reached out to Wunder Mold to learn more about some of the advantages and disadvantages of various manufacturing methods.
Tooling Cost VS Part Cost
Whenever you are considering manufacturing there are two separate costs that you need to consider – tooling and part cost.
Tooling cost refers to everything you need to do in order to start the manufacturing process – whether it is creating a mold, setting up a machine, or assembling a jig. This is typically a one-time expense which you will need to invest in before you can start the manufacturing process.
Once the manufacturing has started, you will be more focused on the part cost – that is the cost to make each individual part – both in terms of materials, human work hours, and wear and tear of the tools you use.
If you are making a relatively simple design, particularly if it is two-dimensional, CNC milling can be a great process for you – it requires almost no tooling costs, provided that you have the machine already.
On the other hand, the part cost can be quite high, as there is a lot of wasted material and it takes a long time to make just one part. Additionally, if you are making a more complex piece, milling will probably not be well suited for that.
Quite opposite of CNC milling, die casting requires quite a lot of preparation in order to create the perfect cast which can then be used to manufacture parts relatively inexpensively by pouring molten material into the cast.
Stamping or Pressing
One more process which is best suited for two-dimensional work is pressing or stamping. This manufacturing method is best suited for manufacturing things made from sheet metal as this material is durable and plastic enough to withstand the process. Certain types of plastic can also be shaped in this way, but the choice of material is fairly limited.
A flat piece of metal is inserted into the press which has the desired end shape. The hydraulic press then presses or stamps the material and the finished product is removed. The process is fast and the cost per part is low, but the initial tooling cost can be very expensive, making this process suitable for high-volume manufacturing.
Blow and Injection Molding
Molding is a very popular technique because it is relatively inexpensive, both in terms of tooling and especially in parts cost. Depending on the item you are trying to make, there are two types of molding available – injection molding and blow molding.
Injection molding is used when you want to create complex shapes made in one piece. The process is relatively inexpensive and can be replicated quickly and with amazing consistency. The downside of the process is that it cannot be used to create hollow parts. That’s what blow molding is for.
Blow molding is primarily used for making plastic bottles. The process is specifically tuned for this task, but it is highly limited. It can only be used for making these kinds of items.
With a variety of even newer processes such as laser cutting and 3d printing, the future of manufacturing is interesting and wide open.