Drakon reinforced extruder

This is remix of old version of extruder designed by AxMod3DPrint (remix actually was made on 04.2017, now original design was changed)
Original https://www.thingiverse.com/thing:2172854

The main idea was to reinforce original design. See comparison screens.
Refer to original instructions and attached photos

The dragon_idler part in this remix has 3 variants
1. Original mbot-dextr-p4.stl
2. Reinforced mbot-dextr-p4b.stl
3. Splitted mbot-dextr-p4.1.stl + mbot-dextr-p4.2.stl (to avo