Cutting steel pipes evenly is a difficult task. Heck, even marking a straight line all the way around the pipe is tough. You can solve this problem with a little masking tape.
The video above demonstrates how to use masking tape to make bandsaw cuts easier and more precise. Start by marking the location on your pipe that you want to cut. Then apply your tape at this mark and overlap it while keeping it lined up. The tape will then serve as an accurate visual guide when cutting the pipe using your bandsaw.
Bandsaw Straight Cuts on Round Pipe [StaceyDavidsGearz (YouTube)]