easy bottom bracket question

All frames that I know of come pre threaded. You need to find out what kind of bracket your frame has, then buy a right BB. And I don't really get what your talking about frames getting drilled, could you explain a bit more.

Swoop said:

ok so I am considering buying a frame and building it up into my dream bike. As I have never done this I am confused about the bottom brackets. I understand that italian and british bottom brackets are basically just different threadings. However, when you buy a frame does the bottom bracket come prethreaded or would you need to have it threaded? Also are carbon fiber frames any different than metal frames? (i.e you have to get an aluminium frame drilled, but carbon fiber is pre drilled because of technical reasons?) thanks.

You sure you're ready for this?

I guess what I meant by drilled was faced or threaded or whatever you wish. The act of cutting the threads into the frame. I was unclear as to whether frames came pre threaded or not. Thanks.