A revolutionary British development could one day change the face of manufacturing by turning every home into a factory.

Engineers are working on a machine capable of churning out a host of household items, including kitchenware, cameras and even small musical instruments.

Not only would the machine make things out of plastic and metal, it would also fabricate its own component parts.

The "self-replicating rapid prototyper", or RepRap, will be about the size of a refrigerator.

It could become a reality within four years and the aim is to make it a universal feature of the home.

RepRap machines could in future render many forms of traditional manufacturing obsolete, according to project leader Dr Adrian Bowyer, of the University of Bath's Centre for Biomimetics.

Computer controlled machines already exist which mass-produce plastic components for industry, but they cost about £25,000. Dr Bowyer's idea is initially to use them to make the component parts for his RepRap machine.

These machines can then be programmed to make further copies of themselves. As the number of RepRap machines grows, their cost is expected to tumble to only a few hundred pounds or less.

Dr Bowyer plans to make the 3D designs and computer code needed for an existing machine to make one of his devices freely available on the internet.

He is not taking out a patent and will not charge a licence fee. "The most interesting part of this is that we're going to give it away," he said.

" At the moment an industrial company consists of hundreds of people building and making things. If these machines take off, it will give individual people the chance to do this themselves."

Rapid prototype machines work by fusing together layers of plastic according to a blueprint fed into the computer.

Dr Bowyer's machine would also be able to incorporate simple metal components and circuits out of an alloy that melts at low temperatures.

The objects they produce would measure no more than 12 inches in length, width and height. Larger items could be made by simply clipping together smaller manufactured parts.

Components the machine is unable to make, such as a lens and computer chip for a digital camera, could be bought separately and slotted in later.

He and colleague Ed Sells have already built a simple demonstration robot with an electrical circuit using the technology.