SMALL BATCH INJECTION MOULDING

THERMOPLASTIC URETHANE DEVICE COVER

Safety is of utmost importance in mines. Therefore Electro Diesel Group (EDG) wanted to develop proximity awareness technology, which senses vehicle and people movement, in order to warn about danger and take over vehicle controls to avoid collisions.

EDG approached cStream to develop the technology and Technimark was asked to do the industrial design of the enclosures. One of these enclosures was for a mobile unit, which contractors use when entering mines. It is connected to their vehicles to integrate it into the system and radio network.

The main enclosure of the unit is made from machined aluminium and needed to be covered with a rubber enclosure. But the cost, based on the limited quantities required, did not justify an injection mould.

Technimark requested the Product Development Technology Station (PDTS) to further their development and to be able to supply a final product that is of injection moulding quality, but without the high cost involved.

For this purpose the PDTS tested the capability of the modular mould base concept in order to manufacture a mould or cover of thermoplastic urethane. This features large undercuts to fit snuggly over the device.

Products like these are conventionally very expensive to produce with injection moulding. This is due to the difficulty of removing the product from the mould as it often requires human intervention or in a high production environment even robots.

To reduce tooling costs the PDTS designed a mould to produce the covers in low numbers in order to test the economic viability.

The first 500 units were delivered at a unit cost and of a quality that could not have been achieved with any other manufacturing method. The PDTS therefore assisted to validate the longevity of the mould and test the commercial lifespan of the product.

HANDLES FOR AVIATION RADIOS

A manufacturer of portable ground to air radios used in aviation requested the Product Development Technology Station (PDTS) to manufacture plastic handles for a radio. The handles were injection moulded.

The station was responsible for the injection mould design after the client provided the CAD model for the handle. The handle consists of two parts that fit over a sheet metal to form the handle.

The client required a low number of handles for market testing purposes. Therefore the PDTS made use of aluminium inserts for the cavities and 3D printed the cores in MS1 tool steel to keep costs as low as possible.

The PDTS produced 100 sets of radio handles in polycarbonate plastic for durability. The mould produced by the station was manufactured at a very low cost when compared to conventional tooling and was the perfect solution for a limited run product.

COFFEE BREWING SPOON

The coffee industry has seen major growth over the last few years. The general market is moving away from instant powder coffees towards the use of freshly grounded beans.

There are various means of brewing coffee on the market. Most of these take a lot of time to prepare and can be somewhat messy and expensive.

The Product Development Technology Station (PDTS) created a cost effective and innovative product, called the Coffee Brewing Spoon. The spoon makes a suitable quick cup of coffee without much effort or mess, requiring no consumables.

The Coffee Brewing Spoon consists of two halves. The coffee is scooped with the bottom half, ensuring the correct amount of coffee. The top half clips onto the bottom half. The spoon is then put into a mug and hot water poured onto it, infusing the coffee through the stainless steel mesh. In order to clean it, the spoon is opened and the bottom half with the coffee grind released into a dustbin, after which the spoon is rinsed out.

A comprehensive product development process was followed to produce a final injection mould ready design. The PDTS manufactured a limit run injection mould to confirm the market demand and functionality.

The cost effective limit run process reduced the risk of commercialisation, market entry and allowed further funding to be acquired to produce a high production injection mould tool.

LOW COST INJECTION MOULD SOLUTION

The Product Development Technology Station provides a cost effective injection moulding solution for prototype moulding or limited run production. This is especially useful when a client requires low numbers of a new plastic product for testing purposes or market research in the final material.

Moulds like these are used for products such as enclosures for electronic devices, plastic screws, radio handles, fittings and brackets. Plastic products intended for medical applications also need to be tested in final material to be given CE certification.

A low cost injection mould solution is made possible, by catering for various clients or products, through using only one mould base. Each product has its own set of cavity and core inserts, support plate and ejector pin inserts. Therefore changing the product design during the mould development process will have much lower cost implications than conventional tooling. It allows the client to only invest in mould inserts and not the entire mould base.

Clients can therefore make changes to the design or product, without replacing expensive cavity plates. The cavity inserts are machined from aluminium, which cuts down on machine time when compared to tool steel.

It also reduces the capital risk for product developers, by providing a viable alternative for the manufacturing of injection moulded products.