What’s the common wisdom on the optimum arrangement for the bearings/bushings in relation to the nuts, nozzle and/or center of mass on the smooth vertical rods? I’m still struggling with Z wobble on my printrbot GO (v.1) and would like to address it as thoroughly as possible.
My thinking is that additional bushings/bearings on the smooth rods should add stability (the primary issue seems to be the gantry rocking back and forth along the Y axis) and ideally the bushings/bearings should be as close to the height of the nozzle as possible. If the gantry’s major pivot point is at the same height and in line with the nozzle (along the Y axis) then any rocking or unwanted movement will have minimal impact on the print quality. Does this make sense?
And is the relationship (in the Z or Y direction) between the bushings/bearings and the drive nuts important also? And what about the center of mass of the gantry? It seems to me that having the nuts and bushings/bearings in line with the center of mass might prolong the life of the bushings/bearings, but what would the impact on the print quality be if any?
Obviously I’ve got lots of questions at this juncture, so please feel free to direct me to articles on the subject or otherwise drop some knowledge on me. The mods I’m considering are non-trivial, so I’d love to know what others have found as much as possible before diving in.
Thanks!