Never understood using flat scrapers on round bottles so I searched out and bought a 2.75 in to 3 in. muffler adapter at a local parts store. Cut it in half lengthwise and ground/filed the edges smooth. The curved half-circle edges already have bevels. Thought about attaching a handle, but it works fine without any. It works fantastically and I can switch between the two ends depending on the actual bottle diameter. And now I have two to share the task.
