Help...
 

I am making a ipod I uploaded it on here but I wanted to add the ports to the bottom of the ipod well I forgot how to take out a peice of the nerbs cylinder to make a hole ? if you don't understand what I mean here is a pic of it I want to subtract the red part from it......

there

draw a curve that you think matches the hole, project curve on object, perform a trim, (delete history) then duplicate the curve, put it into the object, perform an extrude, then a planar of the duplicated curve... that should do it.

thanks it worked