What's the Angle, Kenneth
Each segment of the chassis was defined by three things: the angle of the cut on each end, and the length of the longest "side". Yes, I know, round tubes don't have sides. Get over it.
The angle gauge was set using a digital protractor, which was then transferred to my bandsaw.
The first cut was made, and a digital level was zeroed on the freshly-cut miter. The bandsaw was then reset to the angle for the other end, and the digital level used to ensure that the miters would clock correctly. Incorrect clocking would result in the frame being helix-shaped, not circle-shaped.
Unfortunately, I lost all pictures of this part of the construction when my phone went boots up.
Apple iPhone 5s, f/2.2 @ 4.15 mm, 1/30, ISO 50, No Flash
© Alan Lapp and Zina Deretsky