After some design changes to the Right Side Z-Axis block the rod will still pop-up every now and then. This very simple rod stop will help stop that pesky rod from moving to far up and out into open space. The two files are 123d Design and stl. You can change them to suit your printer if needed in 123d Design.Very simple, undo the bolt nearest to the rod hole. Align and place the stop so the two end clip around the edges and the dome fits into the hole. Then simply place the bolt back and tighten up.