Posted March 23, 2021

Moving From Prototype to Production: CNC Manufacturing Guide 101

Using CNC milling to create a prototype part

Before a product transitions into full production, companies produce it in limited numbers for testing and validation. Most industries know this process as prototyping. For parts manufactured by CNC machining, engineers rely on prototyping to test their design’s form fit and function before moving it into full-scale production. Here are some details that you should know when moving a design from prototype to production.

Building a Prototype Part with CNC Machining 

Building a prototype of a part before full-scale production is a normal part of the product development cycle. Parts fabricated by a machine shop use prototypes for proof of concept to verify the design and resolve any questions about it. Designers use production-grade prototypes to test for form-fit-function (F3 or FFF):

  • Form: A prototype is necessary for engineers to test the physical properties (shape, weight, aesthetics, temperature, etc.) of the machined part and validate that they can build the design to specification. 
  • Fit: Design engineers use the prototype to test whether it will fit where it belongs in the complete system and interfaces correctly with all other system components.
  • Function: The prototype confirms that the part will perform its designed functions without any problems. Functional tests include strength, chemical and temperature resistance, elasticity, and other performance metrics. 

Sometimes a prototyped part has a different surface finish, as the rapid development is more critical than its finished appearance. Once a product design team verifies the prototype’s form, fit, and function, they may iterate another round of prototypes to verify the finish before committing to a finish for the part’s production run.

The standard goals of a prototype’s form, fit, and function vary depending on the need. For instance, plastic often substitutes metal for a prototype to save both time and money. This part may not undergo function testing, but it can quickly prove the design concept and the form and fit. A similar scenario applies to prototyping parts that companies plan to manufacture using injection molding. Due to the high cost of tooling for injection molding, these parts are often CNC machined for a quick and inexpensive prototype.

Designers order prototypes from the CNC machine shop using an instant online quoting system. These systems typically have an automated design evaluation system coupled with the ordering process that checks the customer’s CAD model’s manufacturability. An evaluation system’s near-instantaneous response helps reduce the development time of the part by flagging potential manufacturing errors in the design. These errors often get overlooked in a prototype part and include holes that are too deep or holes with a flat bottom, making them non-manufacturable.

Once your prototype part has been tested and validated, the next step is to move your design into full-scale production.

What you Need to Know when Moving from Prototype to Production 

Before entering full-scale production, the designer needs to ensure they complete the following for their design:

  • Corrections: Prototyping proves the design concept and form-fit-function, revealing potential design flaws and errors that a designer must correct before the part goes into production. 3D software allows designers to implement corrections before production quickly.
  • Certifications: Some industries, such as aerospace and medical, require certification of their products for their intended use. A company must complete certification (if one of the prototypes' purposes was to obtain certification) before full production begins.
  • Documentation:  Prototype documentation isn’t always as complete as it should due to the rush to get the part through its development and may need updating. A team must complete all manufacturing documentation with pertinent data and specifications to proceed with the part’s production.

Once a team has validated and resolved all the aforementioned issues, they can move the prototype to full-scale production.

The process of ordering a part for production is the same as with a prototype, although the customer’s procurement team typically files the order instead of the engineering department. CNC mills and lathes still complete manufacturing operations, but the shop may build multiple parts simultaneously using different production fixtures. Prototype and production parts have similar pricing for fabrication, but higher quantities may cost less per unit depending on the requested finishes. The advanced software and equipment at a CNC machine shop provide the lowest possible priced parts in either case.

Designing a part that will move from prototyping to production manufacturing is bound to create additional process questions. Fortunately, an industry expert can provide answers at your local CNC machine shop.

How A Tech-Powered CNC Machine Shop Can Help 

The machine shop has built its business around fabricating the highest level of quality parts for their customers. They are accustomed to collaborating with customers and answering their questions about part design, design for manufacturability (DFM), materials, and finishes. For example, they will often recommend less expensive materials for prototypes that only require validation for fit.

The CNC machine shop will provide feedback on your design to help the part move as efficiently as possible from prototype to production. Not only will you end up with a better design, but the shop will set up the part for full-scale production at the same location. Consolidating manufacturing at the same vendor saves the time and money you would spend moving the design between manufacturers.

At Plethora, we use a wide variety of the industry's most advanced CNC machining equipment and software to manufacture parts for our customers. Whether it is a rapid prototype or a long-term production run, you will get the highest quality parts possible. Our online DFM and quoting systems are ready to receive data so we can begin working on your next project. To get started, upload your design files to Quote My Part or call us at 415-726-2256.

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The Plethora Team

The Plethora team is your go-to CNC manufacturer for hardware done right the first time. We have the tools and experience needed to create high quality custom parts quickly and with precision, whether you need a prototype or production run.

Topics: materials, Design, Manufacturing, finishing, CNC machining, Quality, Prototyping, Manufacturing Guide