A popular way of constructing multi-part objects for Shapeways is by just sticking them together. If they overlap, the printer will print them out as one single object. A simple example is this object, made by placing one cube just slightly inside another one:

This will print out just fine, but there’s a catch: the total volume is calculated as the sum of the individual volumes before the merge (yes, we’re working on improving that). It would be cheaper for you in this case to fuse the overlapping parts.

You can easily avoid this by properly fusing the objects together in your 3D app before exporting them. This is done with a ‘Boolean’ operation.

Booleans come in different kinds:

Union ( A + B ). The resulting object contains all the volumes of object A and object B. In other words, this operation properly joins two objects together.

Difference ( A - B ). This operation ‘cuts’ object B out of object A.

Intersection ( A n B ). This operation leaves the part where object A and object B overlap.


Below you’ll see our two joined cubes before and after the Union operation:

Please note: Boolean operations do not always create nice and clean meshes, so I recommend you do this only as a final step before exporting your object for 3D printing.


Thanks for shapeways to provide such detail tutorials. This is a translated version.