Control Techniques - Driving British Films Forward

Control Techniques' simple AC drive, the Commander SK, has been selected as an essential component in a revolutionary rotational casting machine designed and manufactured by Ethical Innovatory Solutions (EIS). One of the first companies to own a Rotacaster is Cod Steaks, a world leading special effects and model making company who made all the props for Oscar winning Wallace and Gromit film "Curse of the Were Rabbit"

Production capacity of props has significantly improved due to the installation of the dual axis machine that evenly distributes moulding compound within an empty mould, to create a hollow and light weight model. Matt Sanders, Construction Supervisor and Model Designer for Cod Steaks states "It is at least three times faster than thermo-casting for example, the new machine gives a perfect, bubble-free casting in just a matter of minutes."

Customers such as film and television companies, theatres, and promotional and advertising agencies often have tight deadlines, the Rotacaster has made meeting these deadlines easier. Matt Sanders continues "With a recent order for robots used in an advertisement, we were able to sculpt the models, produce moulds, cast parts for three complete robots, paint and finish them in just two weeks."

The Rotacaster has been developed to fill a hole that EIS identified in the casting industry. Precise and independent control of acceleration, final speed, and deceleration of both axes is crucial in producing a quality casting, whatever the moulding material may be – two-pack resin, plastics or even concrete. The level of control is provided by two Commander SK variable speed drives, one for the turntable that spins the mould and the other for the primary arm which, gives complete 360o movement of the mould.

The Rotacaster also has a "Rock and Roll" feature – ideal for long, narrow moulds that require a gentle rocking motion instead of a complete spin.

In this mode, the primary arm is controlled by two adjustable proximity switches that limit the degree of swing, whilst the turntable simultaneously rotates at the required speed.

Ewan MacPherson of EIS, a design led company that covers a wide range of niche industries, chose the Commander SK drives for the project for the following reasons "The drives are virtually 'plug-and-go' as all our settings are stored on a memory stick , this allows us to load the key parameters to each drive in seconds! We seal the drives in a tamper-proof cubicle, so we have to be completely confident in their reliability – and we are."