Z drive bed assembly

This system works with this scaffold assembly LabBot build

It is based on this function, zbed_assy_wider_threadedrod_noextrusion_higher, found in bom_zbed_moveup.scad

300mm x 400mm bed
2 threaded rods 582mm
4 smooth rods 436mm
2 nema17 with 375mm shaft
bearing_mount_smz (need 2) bearing_mount_smz bearing_mount_smz.stl
motormount_smz (need 2) motormount_smz.stl motormount_smz_dual_mirrored.stl
clamp_bottom_simple_m8_smoothrodholder_for_z (need 8) clamp_bottom_simple_m8_smoothrodholder_for_z.stl
4 smooth rods m8 437 mm long 2 2020 extrusions 437mm long
2 nema 17 with rod 377mm long
T8 nut anti-backlash (need 2)
bed_attach_assy_tslot (4 of them) front_threadedrod_bed_adjustwheel_tslot.stl
bed_bar_clamp (4 of them) bed_bar_clamp.stl
extrusion_threadrod_clamp_noextrusion (4 of them) extrusion_threadrod_clamp_noextrusion.stl
lm8uu_smz_glider_wider (4 of them) lm8uu_smz_glider_wider.stl
zbedslot_516_smz_zbed_wider (2 of them) zbedslot_516_smz_zbed_wider.stl
endstop support endstop_z.stl