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Innovation Design Engineering (MA/MSC)

Maximillian Medhurst

Max is a passionate design engineer who loves the challenge of tackling open-ended problems and creating innovative solutions. He graduated with a distinction in Mechanical Engineering from the University of Cambridge before starting the Innovation Design Engineering double-master program at the Royal College of Art and Imperial College London. In addition to his strong technical background, Max has a wealth of hands-on practical experience and has brought a variety of ambitious projects to life. This combination of skills enables him to take a rapid experimental approach to design, leading to solutions that are practical, effective, and innovative.

For his solo major project this year, Max developed OpenMould - an accessible and affordable mould-making system for the localised plastic recycling community. This community collect plastic waste on a local scale and turn it directly into new products, normally using injection moulding. Current moulds are expensive and difficult to develop, but OpenMould gives recyclers the power to design, experiment, and innovate with the products they produce.

Max is also progressing with his group project, The Waterless Washing Company, which has reached the finals of the London Mayor Entrepreneurship competition, find out more at

The world has a plastic problem, globally less than 16% of plastics are recycled, with the rest being burnt or sent to landfill. We desperately need to change this, by finding new ways to deal with waste plastic. Localised plastic recycling completely re-thinks the way our current recycling model works and OpenMould can help ensure this new model's success.

The localised recycling process — Currently, localised plastic recyclers collect plastic waste from their community and use open-source machines to shred it down and injection mould it into new products. The moulds they use are either CNC machined, making them expensive, or made from stacked laser-cut metal sheets, which produce uninspiring 2D products.
User interviews — Speaking to these recyclers, I found that they all wanted to design and produce their own moulds but found the process too inaccessible and expensive, so resorted to off-the-shelf moulds. I wanted to challenge this and allow them to inexpensively produce moulds themselves, letting them experiment and produce more interesting recycled products – enhancing their business and helping them recycle more plastic
OpenMould — OpenMoulds are durable composite moulds that can be produced almost anywhere, using only a 3D printer and an OpenMould kit. These moulds can be highly detailed and virtually any 3D shape. Their metal surface produces an excellent finish on the plastic parts and the epoxy resin backing that contains fine metal powder to give excellent heat dissipation and fast part cooling times.
Products made with OpenMould — OpenMould allows localised recyclers to produce all sorts of recycled plastic products. Their current craft-style items, like coasters, can be enhanced by adding logos or 3D patterns. High-value products, such as furniture, can be made by combining custom plastic parts with other sustainable materials. Finally, production runs of products for start-ups can be made locally and sustainably.
Making an OpenMould — Users start by 3D printing their design and then spraying it with an innovative conductive spray paint which simultaneously smooths the surface of the print. The print is inserted into a reusable silicone block where it can be electroplated to deposit a layer of copper. With this complete resin is poured in to make up the rest of the mould. Finally, the original 3D print is heated and peeled away leaving the finished mould.
Cost of OpenMould — An OpenMould starter kit contains everything needed to make 3+ moulds, apart from a 3D printer. The kit will cost £150-£200, far less than a single CNC mould which typically cost £500 or more. Each OpenMould only costs around £20 in consumables, allowing recyclers to experiment and iterate with designs and test out ideas. All consumables used can be recycled and used to make new moulds.
Partnering with localised recyclers — To validate OpenMould I worked with a localised plastic recycler called Precious Plastics Lancaster. They were able to test a series of OpenMoulds with their large injection moulding machine, using waste plastic collected from their community. Three test moulds were produced to demonstrate the different potential uses for OpenMould and different types of products that could be produced.
Enhancing recyclers existing offering — Localised recyclers currently produce generic craft-type products, such as coasters and keyrings. They use off-the-shelf moulds - meaning everyone produces the same few items. With OpenMould, recyclers can enhance this offering, adding custom designs, logos, and branding to make unique and desirable products. To show this we produced customised IDE coasters which all came out looking amazing.
Producing high-end products — OpenMould can also help recyclers produce desirable high-end products such as furniture, combining custom plastic parts with other sustainable materials. Injection moulding allows complex 3D parts to be manufactured quickly and easily, and OpenMould makes the moulds affordable and easy to produce. We made these adapter parts for a modern stool design; the parts didn't come out quite as indented but with OpenMould the design can be quickly iterated and improved.
Working with start-ups — OpenMould also allows recyclers to partner with start-ups to make new products locally and sustainably, without the high tooling costs of industrial injection moulding. To demonstrate this we made parts for Click-it, an ex-IDE / current Imperial PhD (collaboration) startup, who are developing a multi-sensory language development tool to help dyslexic children improve their spelling and writing. The parts came out well, and with some iteration, OpenMould could be used to produce their early production runs.

Follow these links to find out more about the amazing work done by Precious Plastics Lancaster and Click-it.

Mould-making experimentation — A long process of experimentation was used to develop OpenMould, trying a wide variety of materials and methods and going through many phases of iteration. Most of my experiments involved producing moulds for plastic buttons as these small moulds let me iterate quickly whilst being a challenging geometry. I tested many of these moulds in a small homemade injection moulding machine to compare their performance and identify areas for improvement.
Early experimentation — I initially tried 3D printing moulds directly, but these could not withstand the high temperatures of injection moulding. I quickly switched to a method of 3D printing a mould-of-a-mould, which was then filled with resin to produce the actual mould. This allowed designs to be easily and accurately produced using 3D printing whilst producing moulds with high heat resistance. Using 3D printing also allows designs to be modified and shared easily.
Metal plating moulds — To improve the mould’s properties, I explored using electroplating to add a metal layer to the surface. This worked particularly well with the mould-of-a-mould technique, producing smooth, accurate surfaces with good adhesion between the metal and backing material. To improve the process, I developed my own conductive ink specifically for these 3D prints. This contained a solvent to gently smooth the surface - removing layer lines and producing higher quality parts.
Simplifying the process for users — I also developed a series of silicone blocks that improved the electroplating and resin-casting steps for the user. These have built-in electrical connectors to simplify the electroplating, include features common across every mould to reduce printing time and simplify the mould design process, and are shaped to reduce the volume of electroplating liquid needed.

Please get in touch if you'd like to hear more about my development process or to discuss the project in general.

Royal Commission of the 1851 Exhibition