Reducing Build Time with Part Orientation

Which part orientation will build fastest?  Both part are identical in size (left part is 12 x 4 x 4 inches).

It is always assumed that 3D printing parts with in the lowest Z-axis height will be the fastest build.  This is not always true; the part geometry is not the only factor to consider.  You must also consider the build process of the 3D printing technology. 

For example, FDM technology uses 2 separate extrusion tips for independent support and model materials.  This means each extrusion tip must deposit both materials individually on each layer as required.  Consider positioning your part where less support is required at each layer and therefore only the model material extrusion tip is used and can considerably reduce the time.

Both parts when processed on a Fortus 450mc with the same parameters (.010 layers, sparse fill, normal surface and SMART supports) yield surprising results.  While the bracket standing up is 3 times taller, it takes almost an hour less build time.  See results below:

Positioned in the shortest Z-axis the build time is estimated at 6 hr 27 min.

Positioned up and using less support material, the estimated build time is 5 hr 32 min.

The reason for the time savings is because in the lowest Z-axis orientation the support extrusion tip and the model extrusion tip must take turns depositing material for 300 layers.  While standing the bracket up there are no shared layers of support and model material saving the time of switching between the two extrusion tips to print the part.

However, be sure you evaluate all requirements of the part, not just build speed.  There may be other requirements to consider such as strength, surface quality, etc.

Mark Abshire

Application Engineer, Additive Manufacturing
Computer Aided Technology