Additive Manufacturing: Advantages and Disadvantages for PCB Prototyping
Simon Fried
Ever since its introduction in the 1980s, additive manufacturing has steadily become a more prominent method for producing a variety of increasingly complex and demanding prototypes, as well as finished components and products. All it takes is a CAD model and a modest investment in equipment, and even college students can start prototyping from their dorm rooms.
Product designers and engineers can realize several benefits of using an in-house additive manufacturing system. There are some important points to consider, however, and key decision makers will need to weigh additive manufacturing’s advantages and disadvantages before implementing it in their R&D cycles.
In several industries, additive manufacturing has steadily become a more prominent prototyping and production method.
Advantages of Additive Manufacturing
In-house additive manufacturing offers some significant advantages over working with a contract manufacturer to produce your prototype. Key benefits include:
Reduced Lead Times
If you’re looking to print a prototype of a new PCB or another electronic circuit, working with a traditional manufacturer will carry significant lead times. You’ll have to spend time preparing standard deliverables for your manufacturer and wait for them to fine-tune their manufacturing process for your particular prototype. Lead times only increase if you leave all of the component sourcing and assembly up to an external manufacturer.
Keeping the electronics prototyping process in-house with an additive manufacturing system can similarly eliminate the lead times associated with using an external manufacturer. You don’t need to spend time with the purchase order process, or wait for finished boards to be shipped from an external facility. As soon as your board is finished printing, it is ready to assemble and test. You’ll be able to spend more time testing and revising your designs.
Full Control Over Your Design
If you’re familiar with PCB manufacturing, you know that an external manufacturer may need to change your design to accommodate their processes or materials. This means you lose control over your design and risk receiving a prototype that does not fully reflect your design intent. Producing your prototyping in-house allows you greater timeline control and process visibility, allowing you to maintain complete control over your design.
You’ll also have the freedom to manufacture one-off designs with complex shapes and geometries. Traditional electronics manufacturers simply cannot produce these devices without a significant investment in tooling, and they will require very high-volume runs to recoup their investment. Complex non-planar design may not be possible to manufacture by traditional means.
Immediate Design Revisions
The compressed prototype production and testing schedules associated with additive manufacturing also compress the redesign schedule. Once you’ve decided on proposed design changes, you can immediately build a new prototype and test your modified device. You don’t have to send your modified design back to an external manufacturer and wait for them to fine-tune their fabrication and tooling process.
Keeping additive manufacturing in-house also allows you to implement an iterative, agile manufacturing methodology that doesn’t require approval for each redesign and production run. Design teams are freed from the bureaucratic constraints that are imposed in a traditional R&D environment, giving them more freedom to implement creative solutions to complex design problems.
Nano Dimension’s DragonFly Pro 3D printing a PCB.
Disadvantages of Additive Manufacturing
Of course, additive manufacturing is not a cure-all for your production woes. If you are looking to complement your capabilities with an additive manufacturing system, here are some points to consider:
Limited Material Selection
Currently, additively manufactured parts may require a low-temperature assembly process, due to the range of materials currently available. The goal with prototyping is to try to closely approximate the various aspects of your end product, so you’ll need to carefully consider which available materials will best represent the mechanical and electrical properties in your final product.
With additive manufacturing of PCBs, depending on how niche of an application you are working on, the materials you can use to build your prototype may not accurately reflect the materials used in a highly specialized finished product. However, the electrical properties of widely used materials, such as the FR4 used in standard PCB circuits, can be reliably replicated and deposited by today’s 3D printers, meaning that you can approximate the electrical properties of a standard substrate.
Although polymer substrates do not have the exact same mechanical characteristics as standard FR4, additive manufacturing of PCBs using polymer substrate materials allows easy printing of multilayer boards with fewer fabrication and assembly steps. In addition, dialectric ink does simulate FR4 and has similar properties. As time goes on and additive manufacturing continues to advance, the range of usable materials can be expected to expand, opening the door to printing PCBs that can compete with standard PCB substrate materials in every regard.
Differences in Material Properties
Conventional PCB manufacturing processes involve depositing conductive copper from an electrolytic solution or etching a copper plane on a substrate. This leaves behind solid copper traces with high conductivity. These traces can withstand relatively high soldering temperatures and have the mechanical properties of copper.
Printing conductors with conductive inks, followed by sintering under a near-IR lamp, is a great way to digitally fabricate PCBs with a wide range of form factors on polymer substrates. These sintered conductors have mechanical and thermodynamic properties that differ from their electrodeposited counterparts. However, the electrical characteristics of sintered conductors are sufficient to prototype boards that will be produced with bulk and electrodeposited materials.
Compared to electrodeposited conductive traces, sintered conductive traces have lower mechanical strength and can deform or fracture at high temperatures. This requires using a low temperature solder when attaching components on larger sintered printed circuits. If you are designing multilayer PCBs, sintered conductors on a PCB will also have lower fatigue life than a traditionally manufactured product, thus your prototype may not fully reflect the mechanical properties of a mass manufactured FR4 device.
High Initial Investment and Required Maintenance Expertise
Although simple 3D printers for additive manufacturing of solid plastic parts are cheap, and open-source software is readily available, purchasing a 3D printer for prototyping precision electronics is a significant investment. In addition, while the materials involved can be expensive, you do save significant amounts of time, keep your designs in-house and there are no setup costs. As with any capital equipment purchase, you will need to weigh the costs and benefits involved in purchasing and maintaining this equipment. If you do decide to purchase such a system, you’ll need to have staff on hand to operate the system throughout its lifecycle.
Weighing Additive Manufacturing Advantages and Disadvantages for Your Prototype
Despite the required initial investment and material limitations, you can cut your prototyping time from days to hours with the right additive manufacturing system. You can also fabricate devices that traditional manufacturers simply cannot work with. You’ll have greater design freedom and productivitywith these systems.
If you can reliably estimate that the money-value of time, the reduced prototyping costs, and more flexible R&D workflows offset your investment, purchasing an additive manufacturing system can provide significant advantages to your product, team, and company.
If you’re interested in streamlining the prototyping process for advanced electronics, you can watch your productivity skyrocket when you use the DragonFly Pro additive manufacturing system. Read a case study or contact us today if you’re interested in learning more about the DragonFly Pro system.
A co-founder of Nano Dimension, Simon Fried leads Nano Dimension’s USA activities and marketing for this revolutionary additive technology. With experience working in the US, Israel, and throughout Europe, he has held senior and advisory roles in start-ups in the solar power, medical device, and marketing sectors. Previously, Simon worked as a consultant on projects covering sales, marketing, and strategy across the automotive, financial, retail, FMCG, pharmaceutical, and telecom industries. He also worked at Oxford University researching investor and consumer risk and decision making.