In the Colorado School of Mines Design Lab we have a total of six MakerBot Replicator 2X 3D printers that we received a little over a month ago. Since they arrived, one machine has consistently had a jitter in the X axis during diagonal movement from the rear left to the front right. The other five machines recently developed the same problem. Today we traced down the problem to a molex connector on the X axis stepper motor. It seems that the strain relief on the wire and the movement isolation for the wire are not enough, and that motion happens at the molex connector on the individual sockets. That motion is enough to cause momentary loss of connection which causes the jitter. Below is a video demonstrating the diagnosis of the problem and a partial solution. We are working on a permanent solution and are hoping that MakerBot will also develop a permanent solution for the problem. It is unfortunate that these printers have such poor design and build quality.
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