Lets be honest, thumb knobs which come standard on a CR-10 suck. Small and uncomfortable they’re not practical for the frequent use required when leveling the bed. If you’re doing bed levels often, say in between quick prints, your fingers will be killed to death. So before printing any PetsFang fan ducts, extruder knobs or arm extenders, Z-braces, control box stands, tool holders, drag chains, dual Z axis parts, direct drive conversion parts or any other mod for this printer, numero uno on my print list was this mod. Making repetitive tasks easier should be priority, and as any good hobbyist knows leveling the bed before each new print is critical for a decent first layer. Even when using an automatic bed leveling system it is always good to manually level the bed every now and again just to give the software as much of a helping hand as possible.
These are super super easy to install, they just slip over the top of the existing leveling thumb wheels. That’s it, no unscrewing or unbolting anything, no glue, no drilling nothing. Just pop them onto the inferior thumb screws and start adjusting that bed for first layers that will actually stick.