Threaded rod is, after all, not made to be used as a precise positioning
tool. It is built to fasten and to remain stationary at all times.
Threaded rods can often be slightly bent, and they get dirty very quickly.
“After a year of printing, it can clearly be seen that threaded rods are
not meant for this kind of application,” Daniel explains in his blog
post. “The rod…squeaks pretty loudly during movement and its threads get
full of black goo that consists of dust, oil and metal shavings from the
friction with the nut.”