Converting an old roadie to fix

Hey all,

Just wondering, I have an old Apollo road bike and want to convert it so …

As it already has a bottom bracket, do I need a different kind of one, or can I just get cranks to fit that BB and it will work??

Also when buying cranks for that BB how will I know what size fits or what kind of cranks???

Thanks in advance!!

^ what he said.
Also, Google.
Also, your LBS.

Try here…

and here…
Advanced Search - Fixed Gear Australia

be careful though, these are very uncharted waters.