Notes on making mechanical parts stronger.
Orientation of layers probably most important factor. They pull apart much more easily than lines break.
ePLA / matt: some websites say it is weaker, some say stronger, than normal PLA.
Layer height: Most people seem to say thicker is stronger.
Heat: hotter, and with part fan low / off should give better adhesion.
Extrusion: overextruding might help.
Much of this is the same as trying to make prints watertight.