Abstract: An example three-dimensional printer includes a humidity source, a build material reservoir, a conduit between the humidity source and the build material reservoir, an air source to transfer air from the humidity source through the conduit towards the build material reservoir, and a valve assembly connected to the conduit to control a flow of the air in the conduit while the printer enters an inactive mode of operation. The air source is to remain in an active mode of operation. The air source is controlled to transmit the air in the conduit until the air in the conduit adjacent to the build material reservoir reaches a temperature and relative humidity threshold.

Abstract: A method of three-dimensional (3D) printing is provided. Print data is received, which defines patterns of at least one agent to be applied to a layer of build material. The print data is modified to add a further pattern of a detailing agent to be selectively applied to the layer of build material to generate fracture regions in a processed volume of build material.

Abstract: In one example in accordance with the present disclosure, an additive manufacturing platform is described. The additive manufacturing platform includes a vibrating bed on which a volume of build material is to be disposed. The bed is to vibrate to remove excess build material and operates in at least two extraction modes during a build material extraction period. The additive manufacturing platform also includes a non-vibrating frame to support the vibrating bed.

Abstract: In one example, a pneumatic transport system to transport build material in an additive manufacturing machine includes a conduit, a source of air pressure to pull or push a stream of air through the conduit, a source of build material to introduce a build material into the stream of air, a separator to remove build material from the stream of air, a flow meter downstream from the separator to measure the stream of air flowing through the conduit, and a controller operatively connected to the flow meter and to the source of air pressure and/or the sources of build material to, based on a measurement from the flow meter, adjust a rate of flow of the stream of air in the conduit.

Abstract: There are disclosed methods and apparatuses for 3D printing post-processing. The methods and apparatuses provide a container for an additive manufacturing system, the container for receiving a build volume of fused and unfused build material. The container comprises a connector for connecting the container to a pressure source, and at least one air hole to allow passage of air into or out of the container. When the connector is connected to the pressure source, air flows through the container between the connector and the at least one air hole so as to remove unfused build material from the container and to help cool the volume of build material.

Abstract: A build material management apparatus for a three dimensional printing system is provided having a plurality of conduits to connect to a respective plurality of ports of at least one build material container. Processing circuitry is provided to control coupling of a 5 pump interface to the plurality of conduits to independently set, for at least two of the plurality of conduits, a given air flow parameter for cooling build material in the at least one build material container. A build material container and machine executable instructions are also provided.

Abstract: In an example implementation, a method of extracting three-dimensional (3D) objects includes forming on a vibratory extraction platform, a build cake comprising a fused 3D object encased within build material and vibrating the extraction platform to break apart the build material and sift it through openings in the extraction platform.

Abstract: A three-dimensional (3D) printer includes a selective solidification module to selectively solidify portions of successive layers of a build material on a build platform. The 3D printer also includes a cartridge receiver to hold a removable material cartridge that accepts material from the 3D printer and makes material available to the 3D printer for printing of the 3D object.

Abstract: A device to de-ionize a build material, a method to de-ionize, and a 3D printer system including the device are disclosed. The device includes a housing having an outlet port and an enclosed sieve within the housing. An inlet port is coupled to a first end the enclosed sieve to provide the build material. A drive actuator is coupled to a second end of the enclosed sieve. The housing and the enclosed sieve may be made of a polymer selected from the build material and a chemically-similar polymer to the build material.

Abstract: A build material recovery system for a three-dimensional (3D) printer can include a selective solidification device to create a 3D object using build material, a build processing device to separate the 3D object from unfused build material, a material separating and conditioning device to condition the unfused build material, and a material storage device to store the conditioned build material.

Abstract: A three-dimensional (3D) printer and method of additive manufacture are disclosed. The method includes building a three-dimensional (3D) object via a 3D printing process. After the 3D printing process, the 3D object is contained within a cake comprising the 3D object and partially fused excess build material. The method further includes vibrating the cake to loosen the excess build material. The frequency of the vibration is swept across a predetermined range of frequencies over a predetermined sweep interval.

Abstract: A 3D printer and method include a cartridge receiver to hold a material cartridge that accepts build material into the material cartridge from the 3D printer and makes build material available from the material cartridge. A first conveying system of the 3D printer transports build material for the 3D printing. A second conveying system of the 3D printer facilitates recovery of excess build material from the 3D printing.

Abstract: According to one aspect there is provided a build material processing apparatus for a 3D printing system. The system comprises a sieve to sieve build material, the sieve to receive a flow of build material, a vibrator mechanism to vibrate the sieve at a resonant frequency. A controller is provided to determine displacement characteristics of the sieve, determine, based on the displacement characteristics, a fill state of the sieve, and control a flow of build material to the sieve based on the determined fill state.

Abstract: Example implementations relate to different mixtures of build materials deliverable during a three dimensional (3D) print operation. In some examples, a 3D print apparatus may include a delivery hopper to deliver build material to a print zone of the 3D print apparatus and a plurality of build material hoppers to which the delivery hopper is connected for receipt of at least one of a corresponding plurality of build materials. A controller of the 3D print apparatus may direct that variable proportions of a first build material relative to a second build material are receivable by the delivery hopper from the plurality of build material hoppers during the 3D print operation, where different mixtures of the variable proportions of the first build material and the second build material are deliverable to the delivery hopper during the 3D print operation.

Abstract: A 3D printer and method include a build platform for thermal fusion. The 3D printer also includes a cartridge receiver to hold a material cartridge that accepts build material into the material cartridge from the 3D printer and makes build material available from the material cartridge for printing.

Abstract: A three-dimensional (3D) printer and method including a material cartridge receiver to hold a removable material cartridge to accept build material from the 3D printer and to make build material available from the material cartridge to the 3D printer for printing of the 3D object. A liquid cartridge receiver holds a removable liquid cartridge to make available print liquid from the liquid cartridge for a print assembly.

Abstract: A 3D printing system comprises a pressure system to provide a negative pressure and a hopper having a first opening to receive powder to be used for printing, wherein the powder is received in an open state of the first opening. The hopper has a second opening to guide air from outside the hopper to inside the hopper and has a third opening connected to the pressure system so as to provide for a negative pressure inside the hopper, the negative pressure to overcompensate for the air receive through the second opening such that a pressure being lower when compared to an ambient pressure of the hopper is generated inside the hopper.

Abstract: A system for manufacturing three dimensional objects can include logic to detect, for at least one vessel, a moisture content level corresponding to a build material residing in the at least one vessel. The logic can also adjust a humidity level and a temperature of a gas and a conditioning agent applied to the at least one vessel, wherein the humidity level and the temperature are based on the moisture content level and a temperature of the build material residing in the at least one vessel. Additionally, the logic can initialize manufacturing a three dimensional object with the build material from the at least one vessel in response to detecting the moisture content level of the build material residing in the at least one vessel is within a predetermined range.

Abstract: Techniques for controlling moisture content of build material in a three-dimensional printer are provided. The system includes a vessel to supply the build material into a build material conveying system. The vessel includes an air inlet to receive a flow of air to fluidize the build material. The system also includes an air conditioner to control the humidity of the air and provide a controlled level of moisture content to the build material.

Abstract: A system for manufacturing three dimensional objects can include logic to apply a gas with at least one flow rate to a vessel of a three dimensional printer. The logic can also detect a permeability of a build material residing within the vessel, wherein the permeability is calculated based on a plurality of pressure values detected by a plurality of pressure sensors residing in the vessel, and apply the gas with a predetermined humidity level at a second flow rate to modify the permeability of the build material residing in the vessel. Furthermore, the logic can initialize manufacturing a three dimensional object with the build material in response to detecting the permeability of the build material is below a predetermined threshold.