CNC Rapid Prototyping: The Complete Guide in 2023
When you are searching rapid prototyping services, there has many types for options. Plastic injection molding, 3d printing , CNC machining and so on.
Don’t know what is the right method for your project? In this post you will learn the process for rapid prototyping project, the cons and pros for CNC rapid prototyping.
It is a process of quickly creating prototypes via CNC machining processes. This process is often used in the development of new products, as it allows for quick-turn parts.
CNC rapid prototyping can be used to create prototypes for any material, including sheet metal and solid plastic. The process begins with creating a computer model of the desired prototype. This model is then used to generate a set of instructions for the CNC machine.
Once the prototype is created, it can be tested and refined as needed. This process is much faster and more accurate than traditional methods of prototype creation, such as hand-carving or molding.
CNC rapid prototyping is an essential part of the product development cycle, as it allows for functional testing and validate the design for manufacturability. This process can save time and money in the long run, as it allows for faster testing and design feedback.
Why Choose CNC Rapid Prototyping?
Let’s jump right into the reasons to apply techniques of CNC rapid prototyping.
1. Cost saving
Look at it this way. Besides all technical reasons detailed further, rapid prototyping is some form of fail-safe to prevent you from financial losses. It is frequent that an intricate design of a part does not succeed from a first attempt. It is much better to lose some materials and a bit of time instead of fully loading a manufacturer’s powers to produce sub-quality products. Instead, rapid prototyping enables the testing of a new design before custom machining.
Moreover, in most cases, you want parts produced to be tested for their mechanical properties before managing large-scale orders. Those properties may include harness, fatigue limit, elasticity, rigidify of the product, actual weight, etc. It is also possible that some complicated designs prove themselves to not be viable for the purpose they had been intended to. Launching a small batch of newly designed parts by means of rapid prototyping is a cost-effective intervention.
2. Precise tolerances
It may seem like any machining process is precise to a certain degree. The true value deviation offered by particularly prototype machining is extremely small. It is correct for comparison to other means of prototyping and larger versions of CNC machines used for large-scale orders.
With rapid prototyping, the desired outcomes can be obtained with high precision. It creates solid ground for further manufacture of components.
3. Perfect mimic of a finished product’s design
I do not get tired of repeating the crucial point. It is vital to have a small batch of prototypes to launch manufacturing of a component with a new design.
From the quality assurance perspective, a batch of parts produced through rapid prototyping may serve as an object for further validation. It implies that testing of such prototypes can serve as documented evidence. It is proof that further manufactured parts have the same properties and are of the same quality as their samples tested.
So, what does all this mean? Rapid prototyping may help in obtaining quality certificates required to sell products in some countries. Overwise, samples made via prototype machining can be presented to customers or potential buyers. This way, prototypes also serve the proof of claimed features of a finished product.
Software-controlled manufacturing incorporates multiple machining operations. Rapid prototyping works similarly. As a result, you may receive any design you need. Most advanced equipment units for rapid prototyping are all-in-one solutions for your manufacture.
5. Wide range of applicable materials
The choice of a material depends on a part’s operating temperatures, properties requirements, and other factors. Therefore, you should be sure that rapid prototyping responds to your needs for a particular material.
As well as traditional machines, software-based centers for prototypes incorporate a wide range of materials. It includes metals, woods, plastics, and even foams.
6. Fast turnaround
Rapid prototyping is not called “rapid” for nothing. Batches of custom samples are fairly small, and the process is focused on fast results delivery. As a result, it will not take long from setting an order to testing prototypes.
7. Short run
Rapid prototyping is also called “short-run production.” Allow us to explain. Short-run refers to a production cycle with at least one factor fixed. These input factors can be labor, capital, real property, equipment, materials, etc. While in long-run production, nearly all those variables can fluctuate, affecting the final cost of production, short-run manufacturing is less vulnerable to changes.
Let us give you some examples. A company produced a batch of components within half of a year. It is unlikely that something will change within this period. A supplier would not increase prices for materials, and the equipment involved would not require repair. However, further batches may have another net price per production unit.
Ordering prototypes from a third-party service provider is also short-run production, executed in a period of six months or less. It is a predictable process, and the fixed terms of a contract give you confidence.
But how do you know when it is better to apply for short-run production and when for traditional large-scale CNC machining? As a rule of thumb, rapid prototyping is the most cost-effective alternative for the production of fewer than 10,000 parts or near that. For more exact calculations, you may use calculations for estimated net price per production unit, i.e., production cost formulas.
8. Wide range of finishing options
It is easy to forget about a component’s finishing while paying close attention to its fundamental design. Luckily, CNC rapid prototyping is known for incorporating a range of options to perfect an innovative sample.
The most obvious type of finishing is adding some surface texture and smoothness. Additionally, it may include removal of supports, sanding, or blasting. Then, you may be offered color matching, such as splay or hand painting. The other option available is coating. It may include plating, shielding, or durability coating. You can take it as an extra layer of protection. And the icing on the cake is the addition of inserts or functional assemblies. These make good designs even better.
Let me add another important piece of information, so you would not be confused if you were asked about whether basic, normal, or detailed finishing you need. The three types of finishing typically available offer the following. Basic – support removal only. In other words, it is simple surface finishing. Normal – removal of build lines and light bead blast (SLA only). Detailed – customized finishing in accordance with the specification, including painting, graphics, assemblies, etc.
9. No fixed tooling
As a bonus of prototype machining, there is no fixed tooling by definition. It is highly appreciated if a company or a third-party provider is partnering with cutting tools suppliers. It enables us to involve any equipment needed fast. What is the purpose? To make absolutely any viable design possible to machine further.
Step-by-Step Process of CNC Rapid Prototyping
Do you need thoughtful insight into stages of prototype machining? We’ll walk you through the whole process of CNC rapid prototyping, explaining each step in great detail.
1. Design Ideations
It is frequent that distinct ideations for manufacture and assembly (DFMA) and design for testing (DFT) are prepared. It ensures that the further production and current prototyping are optimal.
2. Generation of 3D files
You may have heard about computer-aided design (CAD) files and respective software. Well, in general, CAD design stands for digital modeling of parts. The highly advanced applications enable the creation of any design with consideration of the dimensions and features of an object required.
There is no other successful solution for drawing prototypes but CAD software. It is so because applications enabling the programming of CNC machines are based on CAD files. Therefore, The 3d files generation is convenient for designers to manifest their ideas fully, engineers to consider technical characteristics, and specialists to prepare computer-based machining centers.
3. Identification of production sequence
It is another tricky stage to make sure that a production line comprising CNC machines has a well-defined set of machining operations for a particular component. It may be that a single highly versatile equipment unit implements all the procedures. In any case, the production sequence is to be selected by respective specialists.
4. CNC programming
Learn more about pre-programming and preparation of components. Also, read our other blog posts about CNC machining.
Complex software solutions enable automatic transfer of CAD files into G-code-based ones. They incorporate machining operations intended and exploit ideation. Such a procedure makes it possible to command a machining center to move, turn, and feed cutting tools and/or workpieces. This stage requires a complete understanding of processes to eliminate all potential errors.
A manufacturer rarely employs specialists capable of perfecting CNC machine programming. This part is frequently done by third-party service providers, such as ones offering rapid prototyping.
It may take a while to eliminate all potential errors preventing the CNC machine from delivering repeatable outcomes. At this stage, both machining processes and the ideations designed should be finally optimized.
To satisfy a customer’s requirements and prove the viability of ideation, experts conduct multiple tests, generating respective data. It is to be analyzed further, and a suitable prototype to be chosen.
Limitations of CNC Rapid Prototyping
Let’s be honest. None of the machining or any other manufacturing techniques and processes are deprived of all the disadvantages.
Here is the list of ones relevant to CNC rapid prototyping.
1. Production costs
It is why many companies prefer not to make prototypes on their own, letting third-party service providers do the job. A manufacturer may require only one or two prototypes a year. But companies offering CNC rapid prototyping exploit their equipment fully, thus justifying initial capital investments.
Therefore, rapid prototyping cannot serve as a replacement for traditional methods of CNC machining. It is mainly intended for producing small batches of samples for testing.
2. Wastage of materials
It is also a con that you are unlikely to sell prototypes, even if they comply with all technical requirements. It is so because they may not have a serial number engraved and may not have proper packaging. They are not considered parts of a production batch. However, you may present prototypes to potential buyers to interest them in your products even more.
3. Require skilled labor
The strategy requires innovative approaches, creative vision, substantial experience, knowledge of the procedures for testing and errors finding, etc. Likely, even masters of CNC machining cannot make prototypes without previous training. Isn’t it more cost-effective to let already trained teams do their job?
It is cost-effective for manufacturers to collaborate with a third-party provider to make prototypes or small batches of components.