Abstract: Certain examples relate to a build material management system to transport build material from a collection to source to one of a plurality of storage tanks. The storage tank is determined by a controller that compares color of the build material measured by a color sensor with predetermined values. The controller routes the build material to the storage tank.

Abstract: Apparatus is described comprising a chamber (101), which further comprises an interior (130), a sensor (102), a fluid dispenser (103) and a controller (104). A 3D printed object can be disposed in the chamber (101). The sensor (102) is arranged to weigh the chamber (101) or the whole contents of the chamber (101). The fluid dispenser (103) is arranged to dispense fluid into the interior (130) of the chamber (101) and the controller (104) can determine the weight of the 3D printed object and control the fluid dispenser (103). A system and a non-transitory machine-readable storage medium encoded with instructions executable by a processor.

Abstract: Certain examples relate to a storage tank loading system for loading powdered build material to a storage tank and generating a quality indicator. In these examples, the quality indicator may be generated by comparing a measured color with at least one predetermined threshold value, in these examples, the color of powdered build material is determined by a color sensor.

Abstract: Certain examples relate to a build material management system to transport build material from a collection to source to one of a plurality of storage tanks. The storage tank is determined by a controller that compares color of the build material measured by a color sensor with predetermined values. The controller routes the build material to the storage tank.

Abstract: An example of an apparatus is disclosed. The apparatus comprises a controller to obtain a desired quality level for an object to be printed based on an input. The controller is also to determine a ratio of a first build material and a second build material based on the desired quality level. The first build material is a higher quality build material than the second build material. The controller is further to prepare a mix of build material of the determined ratio to be used during generation of the object.