Often prints are too big for our printers, and as a result prints need to be split up into multiple sections. It is critical that when splitting parts into multiple sections that you have some sort of a joint system. Figure 1: Bad Joint, serves as a bad example.
Figure 1 : Bad Joint
When making a joint system, please use the assembly and clash check tool in your CAD program to make sure your parts will fit back together. It is also critical that joints have appropriate tolerance so that parts will appropriately fit together. See the tolerance section under the printer you are using for specific details.