Z-axis is stiff when attempting to rotate in the y direction.

Also very stiff when pushed in the Z direction on the supported side (held by the belt and stepper). However, the non-supported side does have flex. Its essentially acting as a cantilever bed as the carriage isn't fully constraining that end.

With about 10lb of force applied, Z on unsupported side will move up and down about 0.9mm.

On the plus side the linear rail on the unsupported side is not binding yet. Normally you want belts or screws driving both carriages to avoid binding (https://reprap.org/forum/read.php?397,756640, https://drmrehorst.blogspot.com/ has great info, eg two z motors is not ideal).

TODO:

- measure flex with unsupported side carriage removed (to simulate a cantilever bed). Another option might be to put dual carriages on the supported Z linear rail and use triangular support of the bed.

- extend 2020 to meet face of L bracket, see if it provides additional stiffness

- measure max weight Z axis can hold