I want to build my Degus a big cage, but how?

Have you considered a modified C&C cage?

They're meant for guinea pigs - instructions are available at http://www.guineapigcages.com/ - but many people use the same materials to build cages for other animals. They have a photo gallery so you can see how other people have adapted them.

To better suit degus, you can use grids with smaller openings, a deeper base, a top, an added "dig area" made out of a plastic bin - really, there are all sorts of possibilities.

Be creative! Don't feel limited to wood and wire mesh, there are all sorts of materials out there that make great cages.

Degus need a large glass tank which they are unable to chew. They need enough depth to burrow & plenty of items to gnaw in order to keep their teeth trim.

don't use wood they will eat it you have to use metal and glass no plastic either.

look on the internet