A New Zealand university design student says there has been "phenomenal" interest in his 3D printing invention that offers an alternative to the traditional plaster cast.

Jake Evill from Victoria University in Wellington is developing what he calls the Cortex Cast, which uses 3D printing to create a lattice-shaped nylon cast based on X-rays and a 3D scan of the broken limb.

It is more lightweight, breathable and hygienic than fibreglass casts and still provides enough support to allow the bones to heal, all while allowing the limb to be scratched.

According to his website (http://jakevilldesign.dunked.com/cortex) the Cortex is also showerproof.

The prototype, which cost him around $NZ105 ($A91) to make, has attracted an enormous amount of interest on news websites and design blogs.

Although it was still early days, the project had taken on a life of its own because of the phenomenal interest it had generated, Mr Evill said.

His inspiration came from his first experience of a broken bone and having a plaster cast.

"I was surprised by just how non-user friendly those cumbersome things are," he said.

"Wrapping an arm in two kilos of clunky, soon to be smelly and itchy, plaster in this day and age seemed somewhat archaic to me."

The structure of bone gave him inspiration for the lattice shape of the Cortex.

"This natural shape embodied the qualities of being strong whilst light just like the bone it is protecting within."

A computer would determine the pattern and structure of the cast, with denser material around the fractured area of the bone to give more support.

The cast would typically be 3mm thick - allowing people to wear long-sleeved shirts - and weigh less than half a kilogram.

Mr Evill said he still had a lot of work to do on the cast, and was looking for partners to make it a commercial reality.