Dust extraction flexible segment

thingiverse

The print produces a tiny ring burr on the inside surface of the bottom section. It's advisable to leave it intact rather than filing or sanding, as this results in a snugger fit. I've de-burred several sections and found them to be excessively loose afterward. The Autodesk file has been included so you can tailor it to suit your needs. I designed these 68mm segments for use with UK downpipes of that size. These initially arrive from the printer as a tight fit, but they do assemble with some gentle manipulation.