I got a used Lulzbot Taz 4 from Noe and Pedro Ruiz(https://www.youtube.com/playlist?list=PLjF7R1fz_OOVgpmWevin2slopw_A3-A8Y) that needed some repairs. In this video I am replacing the threaded rods.
Threaded rods – https://itworks3d.com/product/lulzbot-taz-45-z-axis-lead-screw-threaded-rod/
This is the upgrades I have done to my Lulzbot Taz 4 and the enclosure I built for it.
http://www.thingiverse.com/thing:866604 – X Axis Openbuilds v-slot
http://www.thingiverse.com/thing:949082 – Y Axis Openbuilds v-slot
http://www.thingiverse.com/thing:755184 – Strengthened extruder body
http://www.filastruder.com/products/all-metal-e3d-v6-hotend – E3Dv6 Hot end
https://www.lulzbot.com/store/parts/lulzbot-taz-pei-sheet – Lulzbot PEI Sheet
http://devel.lulzbot.com/TAZ/cat_guard/ – Cat Guard (enclosure)