I love 3D printing... when it works.
Recently, a friend of mine moved away because of a new job opportunity (congrats!). Naturally, I inherited his 3D printer. After a few prints I started to see this pattern showing up in the prints:
Unwanted lines showed up in my prints.
They are ghost lines because they were not in the design and show up randomly on the prints, and they always show up later in the printing process, not in the beginning, while I was not looking 👀
Because I live in a wooden structured apartment with squeaky floors, so naturally I thought it was because the vibration on the floor caused the issue. So I moved my printer to a corner of my closet, where 3 planes meet. This is the most stable location I could find at my place, I thought I could bust those ghosts in the closet.
But it didn't help.
The lines are all over the place, and it got worse: the print didn't even stick to the bed anymore! My first problem didn't go away, and I have another one?!
It is now July in SoCal, summer heat is cooking me and everything I own in my second-floor apartment. I thought the print failure might be due to the high temperature, so I left my printer alone for a week hoping to tackle this issue on a chilled night instead.
After I refilled my patience and came back to the printer. Another online research session revealed that one or more axes might had weak coupling to the motors when I moved the printer. I loosen all the bolts, and try to move the Z gantry away, so I can adjust the other axis. As I rotated the Z-axis coupler, I noticed something weird:
the Z gantry was reluctanted to rise.
It turns out the loose coupler caused all my issues: the ghost lines and adhesion problem. I saw lines in my prints because the z-axis didn't move as high as it was supposed to; my prints didn't want to stick to the bed because the extruder was scraping the top of the unfinished prints, so the horizontal movement pushed the prints off the print bed. Once I tightened up the coupler, I immediately started a print. It was flawless.
