Abstract: A non-transitory machine-readable storage medium is encoded with instructions executable by a processor. The machine-readable storage medium includes instructions to modify data representing a three-dimensional object model, the three-dimensional object model for use in generating a three-dimensional object in a build chamber. The data is modified to include a container to substantially encapsulate contents of the build chamber comprising the three-dimensional object and non-solidified build material. A wall of the container comprises heat transfer control elements to control dissipation of heat from the contents of the container.

Abstract: A computer-implemented method is disclosed. The computer-implemented method comprises receiving data indicative of a post-manufacture treatment to be applied to a three-dimensional object following completion of a manufacturing process to generate the three-dimensional object; and determining, based on the received data indicative of the post-manufacture treatment, build parameters to be applied in respect of the manufacturing process. A manufacturing apparatus and a machine-readable medium are also disclosed.

Abstract: In certain examples, a method comprises determining a fusing area density distribution of a build layer from build data relating to a build layer of a three-dimensional model to be printed by an additive manufacturing system. The method comprises, in response to a determination that a region of the build layer has a fusing area density outside of a fusing area density tolerance window, modifying the build layer to define a build layer in which the region has a fusing area density that is within the fusing area density tolerance window.

Abstract: Certain examples relate to generating output print data representing at least one object. Output print data is generated by performing a geometric transformation on a part of object model data representing the identified region. The object model data represents the at least one object to be printed. The geometric transformation may use a transformation parameter which is determined based at least on the object model data and object property data. The object property data identifies a region of the at least one object and associates it with a selected physical property.

Abstract: A method is disclosed. The method may comprise obtaining, using a processor, design data representing an object to be generated in a fabrication chamber of an additive manufacturing apparatus. The method may further comprise determining, based on the design data, that a part of the object is to be generated within a predefined portion of the fabrication chamber. The method may further comprise responsive to said determining, generating, using a processor, data representing an ancillary element to be generated in the predefined portion between the part of the object and a wall of the fabrication chamber. An apparatus and a machine-readable medium are also disclosed.

Abstract: In an example, a method includes receiving, at least one processor, object model data representing at least a portion of a first object that is to be generated by an additive manufacturing apparatus by fusing build material within a fabrication chamber. An indication of an amount of fused build material in a region of the fabrication chamber which is to be below the region in which the first object is to be generated may be determined and a dimensional compensation value to apply to the object model data representing the first object may be determined based on the determined indication. The determined dimensional compensation value may be applied to the object model data to derive modified object model data.

Abstract: Examples relate to a 3D printing and a method comprising receiving a packing ratio of an object to be printed; based on the received packing ratio, determining a mixing ratio of fresh to recycled build material to use for printing the object; and providing the mixing ratio to a dispenser to dispense fresh and recycled build material in the provided mixing ratio for printing the object.

Abstract: A mobile build unit (2) for selectively locating in a build chamber (4) of an additive manufacturing machine (6). The mobile build unit has a build platform (8) to receive build material; and a build unit heater (10) to heat layers of build volume formed on the build platform (8). The build unit heater (10) is movable between a first position in which the build unit heater (10) is stored, and a second position in which the build unit heater (10) is mounted over the build platform (8).

Abstract: In an example, a method includes measuring a temperature of a plurality of regions of a layer of build material in an additive manufacturing apparatus to provide initial temperature values. For each of a plurality of regions which comprise build material which is intended to fuse, an average temperature value of a plurality of neighbouring regions may be determined and the initial temperature values may be replaced with the average temperature value. Based on the replacement temperature values, a representative temperature of an area of the layer of build material may be determined and a heat source may be controlled based on the representative temperature.

Abstract: An example method of generating three-dimensional objects is disclosed. Object generation instructions to generate the object may be determined by defining a shell region of a layer of build material corresponding to the first portion of the object having a first color, and defining a fusing agent region on a layer of build material adjacent to the shell region on which fusing agent of a second color is to be applied and specifying an amount of colorant to be applied to the shell region wherein the object generation instructions specify application of fusing agent and colorant such that, when the layer of build material is heated using a heat source, the fusing agent region of the build material melts due to energy absorbed from the heat source and the build material of the shell region melts due, at least in part, to energy transfer from the fusing agent region.

Abstract: In accordance with the disclosure, there is provided, a method. The method may comprise performing a printing operation to produce a part based on a predetermined fluid strategy. The method may further comprise assessing part data, related to the printed part, for any inaccuracies, based on a printing operation input. The method may further comprise adapting the fluid strategy for a next printing operation, based on any identified inaccuracies.

Abstract: In an example, a method includes measuring a temperature of a plurality of regions of a layer of build material in an additive manufacturing apparatus to provide initial temperature values. For each of a plurality of regions which comprise build material which is intended to fuse, an average temperature value of a plurality of neighbouring regions may be determined and the initial temperature values may be replaced with the average temperature value. Based on the replacement temperature values, a representative temperature of an area of the layer of build material may be determined and a heat source may be controlled based on the representative temperature.

Abstract: Example implementations relate to controlling the application of layers of build material in 3D printing. One example implementation determines a temperature at a predetermined location of a layer of build material following fusing according to an object model, where the predetermined location is dependent on the object model. The application of a new layer of build material is controlled dependent on the determined temperature.

Abstract: A method is described in which data representing a plurality of three-dimensional objects to be printed in a printing job is received and printer control data is generated based on an attribute to be prioritised for each object. The plurality of three-dimensional objects are printed in one printing job by printing a plurality of successive layers based on the generated printer control data. Printing a layer comprising printing a portion of a first object in a first print mode, wherein a first attribute is prioritised, and printing a portion of a second object in a second print mode, wherein a second attribute is prioritised.

Abstract: An apparatus comprises a processor and a machine-readable storage medium storing machine-readable instructions executable by the processor. The machine-readable instructions comprise instructions to cause the processor to create 3D print data including data defining one or more objects to be printed in a build chamber of a 3D printer and data defining, in addition to the one or more objects, a shield to be printed to shield the one or more printed objects in the build chamber to reduce heat dissipation to an outside of the build chamber. The shield is designed depending on a thermal behavior of the build chamber and/or depending on a thermal behavior of the one or more objects to be printed.

Abstract: Certain examples relate to generating output print data representing at least one object. Output print data is generated by performing a geometric transformation on a part of object model data representing the identified region. The object model data represents the at least one object to be printed. The geometric transformation may use a transformation parameter which is determined based at least on the object model data and object property data. The object obtain input print data comprising property data identifies a region of the at least one object and associates it with a selected physical property.

Abstract: In an example, a method includes receiving, by at least one processor, object model data, the object model data describing at least part of an object to be generated in additive manufacturing. Pattern data is also received, wherein the pattern data describes a pattern of variable opacity intended to be formed internally to the object. Object generation instructions for generating an intermediate layer of the object comprising the pattern of variable opacity may be determined by at least one processor.

Abstract: In one example a method of generating a three-dimensional object in a 3D printing system using a fusing agent of a first colour and a build material having a second colour different from the first colour, and a detailing agent, comprises obtaining object model data describing an object to be generated, and determining a first portion of the object to be generated to have the second colour. The method comprises determining object generation instructions to generate the object by defining a gap region of a layer of build material that is to correspond to the first portion of the object to have the second colour on which no agents are to be applied, a band of detailing agent on a layer of build material immediately adjacent to the gap region to define an outer limit of the gap region and therefore a boundary of the first portion of the object, and a fusing agent region on a layer of build material adjacent to the gap region on which fusing agent is to be applied.

Abstract: A system includes a controller to receive data corresponding to an object or slices of the object to be generated by a 3D printer, wherein the 3D printer includes an array of printhead nozzles to selectively eject a print agent on a layer of build material in a build chamber having a build chamber wall, the array of printhead nozzles spanning substantially the full width of the build chamber and moveable along a length of the build chamber. The controller to generate first print data used to generate layers of the object based on the received object data, and to generate second print data used to generate layers of a sacrificial barrier located between the object and the build chamber wall, the second print data is generated such that different parts of the sacrificial barrier are generated using a different plurality of nozzles of the array of printhead nozzles.

Abstract: Certain examples described herein relate to adjusting an energy source of a 3D printing system. In certain cases, a build bed of a 3D printing system is arranged to receive a layer of build material and the energy source of the 3D printing system is controllable to provide energy to a zone of the build bed. The energy provided by the energy source associated with the zone is adjusted based on a difference between a predetermined heat loss of the build bed and a determined heat loss for the zone, where individual adjustments of energy provided to at least some zones of the build bed collectively provide a uniform heat loss across the build bed.