Originally posted on Facebook, but thought it would be worthwhile here for future builders.
Root 4 : Video on how to install the ballscrew on the y axis.
Please note that you should attach the Ball nut to the ballscrew before installation.
I had a bunch of issues and hopefully this helps other people. (just done on my phone with no editing, but it gets the point across).
Root CNC Project
-the y axis mounts are mis labelled on thingiverse.com. FF is the Fk and vice Versa.
Cheers.