FT5 Locking Z movement

To avoid Z-height differences between left and right side of the bed I set up an interlockiong mechanism between both threaded rods.

The pulleys are all made using F625ZZ bearings. Longer bolts through the pulley are M5x30 and are fixed in the 2040-profile.
You will need :
a long GT2 loop that I ordered from [Adafruit](https://www.adafruit.com/product/1184)
2x500mm of 2020 profile to carry the rods
1x500mm 2040 profile for the steppers
2x straight metal stepper supports
4 x 100mm 2020