Anycubic i3 Mega - Y-Axis Rod Bearing Block with Threads

only a simple test in OpenSCAD for "simulating" the parts near the heatbed plate ... in the end for creating a mount for a cable chain for the Y-axis and some other parts inside the housing ... but seems, OpenSCAD cannot handle "real" threads above a very small ammount

the threads-part of my scad-file is completely based on the free downloadable (and not really understood) threads.scad from http://dkprojects.net/openscad-threads/ ... I did only the raw form of the bearing block

this is not