Even though much of the work Brad and I did yesterday was testing (and rejecting) the intital idea for pivot mechanisms, most of the worry in his thought process was about the truss connecting the two poles.
Even with using a rectangular beam instead of a pipework bridge, he’s concerned about the caster under the orbit pole (Mimas) kicking out.
While I’m less concerned about the kick out, I am concerned that with a pressure-fit acetal pivot, there will be nothing structural fixing the bridge to the orbiting door, just physics and trust.
Deep down, I suppose this is a concern about Mimas kicking out, because why would I need to secure the bridge to the post otherwise? It’s not like gravity is going to reverse and pull the truss upward.
In any case. New design adds a stopper ring and capture plate between the pivots and the truss. The plate screws (bolts?) to the post surrounding the pipe.
As an added benefit, this has the ability to keep even more dust away from the pivots.
On the other hand, there’s also a risk that if Mimas kicks out under these circumstances, it could torque the entire structure and pull even the center pole out of joint.
Next steps: keep plugging numbers into the budget spreadsheet and try to convince myself they’re never going to fund me, so I should go ahead and fail bigger.
Edited to add: should we look into having more weight just above Mimas to make the orbiting pole behave in a less top-heavy way.