I would like to present you to connection systemwhich is not primarily for children. : High quality printing is required (no overlay plastic for best connection .Yet parts should be sufficiently free .
One part have about 1 gram so one kilogram can make maybe one -thousand parts :P
You can basically create anything .
(my object scale is 1500%)
the most commonly used parts are cross (male +female part) , 90 degrees (male+female part)