Routing on sub level menus

Hi everyone,

I'm a newbie with Codeigniter and am on my second attempt at a project. I've been really impressed with how easy it was to set up my views and database queries. However I'm stuck with my menu routing.

I have a menu with 4 levels such as:

accessories > audio-accessories > earpieces  > brand
accessories > batteries > nimh  > brand

etc

All are index pages.

I've followed the Codeigniter tutorial and have all my first level pages set up and working but after setting up a controller and routes for accessories I manage to get the first sublevel working but when trying the next using the same format I fail. I'm clearly missing something really fundamental.

Is anyone aware of a tutorial, or examples to do something like this?

Thank you in advance for any help or advice.

Alan