All companies want their parts manufactured as quickly as possible. Faster production means shorter time-to-market, which can provide a commercial advantage and increased profits.
When outsourcing rapid prototyping and production to a third-party manufacturer, you might think that the speed of manufacturing is out of your hands. But this could not be further from the truth: designers and developers can play as large a role in speeding up on-demand manufacturing as the manufacturers themselves.
This article looks at how you can get your parts made faster, from choosing the right manufacturing process to developing an efficient line of communication with your manufacturer.
Choosing a fast manufacturing process
Even the best manufacturers can’t change the fact that some processes are faster than others.
That being said, you don’t always have the freedom to pick and choose between processes. If a production part needs to be cast or forged, for example, you can’t just decide to 3D print it instead. Doing so would drastically alter the function and capability of the part.
It is therefore important to determine which manufacturing processes are possible for a given project.
For rapid prototyping, there is generally a much greater degree of flexibility than with production. Most prototypes don’t have strict mechanical and material requirements, so speed can be prioritized over other factors.
Production parts have stricter requirements. However, a process that makes fast prototypes — 3D printing, for example — will not necessarily be a fast process for mass production.
CNC machining is a relatively fast manufacturing process, especially for short-run production and prototyping. It requires no tooling, and modern 5-axis machines reduce the need for multiple setups.
It is less efficient for large quantities, and there is no economy of scale: making more units doesn’t significantly reduce the time per unit. Machining complex parts also takes more time than machining simple parts.
Injection molding is a two-step manufacturing process that requires the creation of metal tooling. Because of this, it is a slow process for short-run production and prototyping.
But while making molds is a slow process, injecting shots of plastic is lightning fast. This means that each unit of the plastic part can be made very quickly once the tooling is complete. The process is therefore very fast for mass production.
Sheet metal fabrication
It is usually obvious when a part should be made using sheet metal fabrication, so you will rarely have to decide between sheet metal and an alternative.
However, there are a range of individual processes associated with sheet metal fabrication, and the range of machinery required (brakes, shearing machines, etc.) can make rapid prototyping and short-run production slower than with all-in-one processes like CNC machining.
3D printing is a fast manufacturing process for prototypes and very small production runs — typically less than 10 units.
Its speed is down to its very short setup time, though the actual manufacturing time may not appear especially fast. Importantly, 3D printers can fabricate very complex parts at the same rate as simple parts, which makes them different to CNC machines and other subtractive techniques.
Designing parts for fast manufacturing
Fast manufacturing does not only depend on the expertise of the manufacturer. Product designers also play an important role in determining how quickly a part can be made.
Applying principles of Design for manufacturability (DFM) will result in better parts and faster production from your on-demand manufacturing partner.
This means looking at how a part will be made, and tailoring the design to be suitable for the production method — whether that’s a CNC machine, injection molding machine or something else.
But although each manufacturing process has its own unique criteria for part design, there are some universal principles one can follow to speed up manufacturing.
- Simplify complex features: In the majority of cases, needless complexity makes parts harder to manufacture, which increases turnaround times and may also increase costs. Ask yourself whether aesthetic flourishes are worth waiting for.
- Allow loose tolerances: All companies want their parts to be neat and uniform, but time is wasted when demanding tight tolerances on non-critical dimensions. Specify tight tolerances only where absolutely necessary and allow the manufacturer to work quickly.
- Choose a machine-friendly material: Sometimes material choice is determined by the part’s end use, or by the customer. But if there is flexibility, you will save time by choosing a material that is easy to process. CNC machines, for example, can cut aluminum faster than steel.
- Multiple parts per setup: If you require more than one unit of a small-size part, it may be possible to CNC machine multiple units in a single setup, or to 3D print multiple units on the same print bed.
Making life simple for the manufacturer
Once you have designed your parts and identified a suitable process and material, you can still take further steps to shorten on-demand manufacturing time — by making life as easy as possible for your manufacturer.
One of the most important factors in manufacturing is clarity. Double-check your designs for mistakes and ambiguities. Even if your designs are simple and machine-friendly, you may still need to present them in a particular way to convey your ideas to a machinist or other manufacturing professional.
You can eliminate many possible ambiguities by preparing a technical drawing.
A technical drawing supplements your digital design and includes details like tolerances, surface finishing requirements, annotations and other requirements that are not shown in the CAD file itself.
Technical drawings can also be supplemented by notes to the manufacturer, where you can explain your objectives and requirements in natural language. Making these notes clear and unambiguous means you won’t need to continue discussing the project with the manufacturer.
Of course, conveying your needs to a manufacturer gets much easier when you work with the same people again and again. Instead of finding new partners on a project-by-project basis, consider building up a long-term relationship with a manufacturer; you’ll find that miscommunications become rarer and production gets faster over time.
- Is my design error-free?
- Is it clear and unambiguous?
- Are tolerances specified?
- Is all relevant information conveyed in notes & annotations?
- Does the manufacturer know my objectives?
RapidDirect prides itself on the speed of its on-demand manufacturing services. Request a free quote today.