Print works
Nadav Sella, solutions sales manager, Stratasys, outlines the benefits 3D printing has brought to injection moulding
3D printing has been around for 25 years with the technology jumping from being solely a tool used in product development in the design cycle to one deployed across the supply chain in almost all walks of life, including the production of injection moulds.
Traditionally, hard-tooling moulds are made from tool steel with a CNC milling machine or via electrical discharge machining (EDM). When used in mass production, they can last for millions of cycles but cost hundreds of thousands of pounds. What’s more, lead times to produce these moulds are often measured in months rather than weeks or days.
When tens of thousands of injection moulded parts are needed, soft-tooling is an option. Made in aluminium, these moulds are less expensive and faster to produce (two to six weeks).
Unfortunately, the cost and time of tooling moulds is often compounded by factors like design mistakes that require the mould be remade correctly or the need to create multiple iterations before the final part design and quality are achieved. It is with these issues in mind that manufacturers have begun to embrace the use of 3D printed moulds to create functional injection moulding prototypes.
As such, we are witnessing an exciting development in the world of injection moulding whereby companies are beginning to adopt 3D printing for the production of tools for low volume production. Advances in Stratasys’ PolyJet materials portfolio, namely its Digital ABS offering, has enabled companies to take functional testing to a new level. The ability to 3D print tools that can withstand the heat and pressure of the injection moulding process, to create prototype parts in the final product material, enables companies to generate superior performance data and validate certification confidence.
How is this affecting the medical device sector
In a field where innovation saves lives, Stratasys 3D printers empower doctors, researchers and medical device manufacturers to work faster, test thoroughly and customise their devices in new and innovative ways. Beyond the traditional notion that 3D printing is very much a prototyping tool, manufacturers are now realising that more benefits are available to them further down the product development process, including the ability to 3D print injection moulding tools.
PolyJet injection moulds are often cheaper and much faster to make compared with traditional aluminium moulds. The PolyJet 3D printed injection moulding tools do not replace traditional aluminium and steel tools but in many cases, they can be used to obtain the first batch of injection moulded parts, giving customers flexibility in their manufacturing process, saving time and money.
The medical device market is demanding in terms of the number of tests and documentations needed before a product can be released to the market, as well as the special materials that are being used. This makes the lead time reduction with 3D printed tools even more crucial, especially when medical device prototypes can be tested in the final product material before committing to CNC machining.
3D printing injection moulds allows manufacturers easy evaluation of the performance, fit and quality of potential products before mass production starts. If design iterations are required, they can be made in a matter of hours and at a fraction of the cost compared to traditional moulds.
A great example of the tooling benefits afforded by PolyJet technology is Diversified Plastics, a US custom injection moulding company that serves numerous industries including medical. Recently, a medical customer approached it about producing a new medical device that it wanted to bring to market quickly. By using its Stratasys 3D printer to create the mould, Diversified Plastics was able to produce an injection moulded prototype from the same material planned for the final product in one week instead of five ― a time savings of 80%. This allowed the customer’s R&D and marketing departments to evaluate and test the shape, texture, look and feel of the device far faster than in the past.
What’s more, by 3D printing the injection mould, Diversified Plastics cut its tooling cost by 88%.
What the benefits will be in the future
This is a fast-growing application and Stratasys continues to work with companies to help them gain new manufacturing efficiencies with 3D printing technology. Plus, with increased improvement in 3D printing materials, the ability to create customised and complex bio-compatible parts and devices may someday become reality.