**5. Conclusions**

3D prototypes can be done with planar procedures piling up different layers to build three-dimensional structures. The techniques used for manufacturing planar circuits can be adapted to build these prototypes, which can be combined with external elements such as wires or rods.

Different modifications have been shown to improve results in each manufacturing phase; errors and specific features of each machine must be taking into account to reduce its impact in the manufactured layers. Over-cut, under-cut, measurement and estimations are some of the techniques used to reduce these effects.

Regarding the assembling techniques with screws or dowel pins, the issues due to pressure, excess/lack of soldering paste, etc., should be considered. Finally, the use of press covers is also recommended in soldering phases, taking into account that technologies such as RESIW or DRESIW have some variations.

All the information collected in this chapter has been extracted from empirical evidence and real circuits that have been manufactured.
