Tests with suppresed bending
We create short segments of plastic tubes at the same length, with a negligible cut, and wrap them around the rods between spheres. These segments are light (compared to the spheres) but are thick enough to create a lower bound for the distance --- see the difference between Box A1 and A2 below. The most informative occasion is when the length of these small tubes almost fills the entire s_max: in these cases, the combination of the small residual spacing and the thickness of the wall jointly determine a much reduced theta_max than its default. For instance, for N=8, with the theta_max being reduced by a factor of four (see Box B), this reduced flexibility shifts the onset of Mode 1 to the range of Gamma around 2.0, as opposed to what is reported in Fig.4 as Gamma= 1.65~1.7. We also find that the reduced flexibility has also stabilized Mode 1 in the range of Gamma which would be too high for an unaltered chain to maintain Mode 1.
