Creality Ender 3 Pro Assembly Instructions V1.0 23 www.rb42.blog
Step 8 - X-axis idler pulley
1x (07) X-axis idler pulley
Process
Position the T-slot nuts of the (07) X-axis idler pulley so they
are in the same orientation as the channel on the profile.
Wrap the X-axis (14) Synchronous Belt (from step 6) over the
pulley of the (07) X-axis idler pulley assembly.
Move the assemble, with belt wrapped around it, into place
on the right-hand end of the front face of the (18) X-axis
profile and insert the T-slot nuts into the channel of the
aluminium extrusion.