LIGHTWEIGHT, COMPACT AND ROBUST DESIGN

“The brief was simple to begin with – a box for my electric toothbrush”, explains Ged McCall, Schelle founder.

“I travel a great deal on business and I wanted a protective, portable case, something that would prevent my toothbrush from accidentally switching on and draining the battery during my trips. It became a mission to find a solution when I was on a flight, and to my embarrassment, the overhead luggage locker brought on disconcerted looks from fellow passengers as it buzzed”.

Having searched the market for a travel case with no joy, Ged realised there was a niche for a portable electric toothbrush case and his vision was for one that was compact, lightweight and robust. Armed with a basic concept and a 3D printed prototype following help from Lewis Trott design and Loughborough University’s Advanced Manufacturing Unit, Ged met with the technical team at Rutland Plastics.

BOXING CLEVER WITH STYLING FEATURES TO DISGUISE WITNESS LINES

Simon Grainger, Design Engineer at Rutland Plastics, worked closely with Ged to progress the design for manufacturability, discusses the process, “The conceptual design showed the product as a two-part traditional hinged box, and I felt the design would benefit from a living hinge.

Using the flow dynamics of plastic injection moulding means that essentially two bodies of plastic can be connected with a very thin but super resilient hinge. Without the living hinge, the two halves would be separate parts which would require separate cavities, gates and runners. Since a living hinge connects both, the cavity becomes one and will typically reduce the cost to make the mould, and it also saves on assembly.

Internally, it needed to firmly grip the toothbrush body and two brush heads. This required a series of cores and undercuts, which present their own challenges because they hinder a clean ejection of the part from the mould”.

Simon refined the retaining clip mechanism to give durability to the function and he integrated a number of clever styling features to disguise the witness lines left by the side action tool, to include a recessed shape and thumb grip. Acute radius corners and a standard VDI texture combined to create a pleasingly aesthetic and extremely tactile product. Inside the case, a high gloss finish makes it easier to wipe clean.

“We produced a number of prototypes to validate the Schelle case for functionality – for example, to assess how well the snap clip performed, along with checking the fit for the toothbrush body and brush heads”, added Simon.

Prototypes were also invaluable for helping Ged to design a merchandising unit and to demonstrate the products attributes to potential retail buyers.

MATERIAL MATTERS

Rutland Plastics advised Ged on material choices, recommending a polypropylene with an antimicrobial additive, and trialled it in a number of different grades to find the optimum solution.

The tool was made in the UK, tightly project managed by Rutland Plastics. The case is moulded in eight colours, it is dishwasher safe and shatterproof.

Ged confessed that originally his first consideration was to have the product made in Singapore, but decided against this, preferring the convenience of close communications particularly during the evolution of the product’s design.

Summarising the process, Ged said “In the end, I believe the decision to make the design and manufacture in the UK was the right one. The support I had from the technical team at Rutland Plastics throughout the whole process could not have been better. The Schelle case was two years in the making from the seed of an idea to get it to market. It’s been quite a journey”.

www.schelle.co.uk

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