Abstract: According to one example, there is provided a method of distributing build material in a 3D printing system. The method comprises moving a build material support positioned below a hopper, the movement to cause build material stored in the hopper to be deposited on the build material support, and moving a recoater to spread build material from the build material support over a build platform to form a layer of build material thereon, and to return any excess build material back to the build material support.

Abstract: An example two-part seal for a powder-based 3-D printer includes a flexible film wiper attached to a rectangular platform and disposed on linear segments of a perimeter of the platform. The flexible film wiper extends beyond the perimeter of the platform to provide a sliding seal against corresponding walls of a rectangular enclosure of the platform. The two-part seal also includes a deformable member disposed upon the flexible film wiper that extends beyond the perimeter of the platform to apply sealing pressure to the flexible film wiper.

Abstract: According to one example, there is provided a method of distributing build material in a 3D printing system. The method comprises moving a build material support positioned below a hopper, the movement to cause build material stored in the hopper to be deposited on the build material support, and moving a recoater to spread build material from the build material support over a build platform to form a layer of build material thereon, and to return any excess build material back to the build material support.

Abstract: According to examples, a printing system may include a guide rail and a carriage. The carriage may include a rotatable member supported on the guide rail. The printing system may also include a cleaning assembly mounted to the carriage and the cleaning assembly may have a scraper to scrape debris off at least a portion of the guide rail.

Abstract: An example printing device include a frame, a printbar, a lift mechanism, and a lock. The lift mechanism is operably coupled to move the printbar from a printing position to a capping position along a printbar path of travel with respect to the frame. The lock is operably coupled to the frame to releasably engage the printbar in the capping position and disengage the printbar and permit movement to the printing position.

Abstract: A replaceable printing subassembly is disclosed. The replaceable printing subassembly includes a printbar. A fluid delivery system including a pump is fluidically coupled to the printbar. A frame is coupled to the fluid delivery system. The replaceable printing subassembly also includes a lift mechanism having an actuator to selectively move the printbar with respect to the frame.

Abstract: In one example, an encoder strip mounting system includes an encoder strip having a first end, a second end opposite the first end, and an intermediate part between the first end and the second end, and a retainer to prevent the intermediate part of the encoder strip from shifting lengthwise with respect to an anchor point for the retainer located within a span of the intermediate part of the encoder strip.

Abstract: An example printing subassembly includes a frame having first and second members spaced extending in a first direction. The frame can be removably coupled to a printing device. The first and second members are spaced from each other in a second direction, which is orthogonal to the first direction. The first and second directions are also orthogonal to a third direction. A printbar is coupled to the frame. An alignment system is coupled to the frame and includes at least four alignment features cooperating to constrain translation of the printing subassembly in the third direction and rotation about axes in the first and second directions with respect to the printing device.

Abstract: Linear guides for shafts are disclosed The linear guides comprise housings having a main opening to receive the shaft and multiple contact guiding elements, such m bearings or sliders, arranged on the housing and around the opening, each contact guiding element to contact the shaft at a different point The linear guides further comprise thermal compensation blocks affixed to the housing and in contact with a portion of a contact guiding element of the multiple contact guiding elements.

Abstract: A printing subassembly is disclosed. The printing subassembly includes a printbar. A frame is coupled to the printbar such that the printbar dos not move with respect to the frame. A fluid supply system is coupled to the printbar.

Abstract: Drive belt systems and methods thereof are disclosed. Drive belt systems and methods thereof include driving a continuous belt around a drive pulley member and an idler pulley member by the drive pulley member and transporting a transport unit and/or reciprocating carriage unit coupled to the continuous belt in a first direction away from the drive pulley member. Drive belt systems and methods thereof also include applying at least a force to the belt in a traverse direction thereto to direct a portion of the belt about the drive pulley member by a belt stretch management apparatus coupled to the transport unit and/or reciprocating carriage unit.

Abstract: In one example, a temperature control system for a spreader roller in an additive manufacturing machine includes: a first duct to carry air to an air passage through the roller; a second duct to carry air away from the air passage through the roller; a fan to move air through the ducts; a temperature sensor to sense a temperature of the roller; and a controller to control a flow of air through the ducts based on a temperature sensed by the sensor.

Abstract: An example printing device include a frame, a printbar, a lift mechanism, and a lock. The lift mechanism is operably coupled to move the printbar from a printing position to a capping position along a printbar path of travel with respect to the frame. The lock is operably coupled to the frame to releasably engage the printbar in the capping position and disengage the printbar and permit movement to the printing position.

Abstract: An example printing subassembly includes a frame having first and second members spaced extending in a first direction. The frame can be removably coupled to a printing device. The first and second members are spaced from each other in a second direction, which is orthogonal to the first direction. The first and second directions are also orthogonal to a third direction. A printbar is coupled to the frame. An alignment system is coupled to the frame and includes at least four alignment features cooperating to constrain translation of the printing subassembly in the third direction and rotation about axes in the first and second directions with respect to the printing device.

Abstract: A printing subassembly is disclosed. The printing subassembly includes a printbar. A frame is coupled to the printbar such that the printbar dos not move with respect to the frame. A fluid supply system is coupled to the printbar.

Abstract: A replaceable printing subassembly is disclosed. The replaceable printing subassembly includes a printbar. A fluid delivery system including a pump is fluidically coupled to the printbar. A frame is coupled to the fluid delivery system. The replaceable printing subassembly also includes a lift mechanism having an actuator to selectively move the printbar with respect to the frame.

Abstract: In one example, a temperature control system for a spreader roller in an additive manufacturing machine includes: a first duct to carry air to an air passage through the roller; a second duct to carry air away from the air passage through the roller; a fan to move air through the ducts; a temperature sensor to sense a temperature of the roller; and a controller to control a flow of air through the ducts based on a temperature sensed by the sensor.

Abstract: In one example, a build material supply for an additive manufacturing machine includes a container to de-agglomerate a supply of powdered build material.

Abstract: In example implementations, an apparatus and method are provided. The apparatus includes a movable carriage, an energy source coupled to the movable carriage and a plurality of shutters coupled to the movable carriage. In one example, the plurality of shutters is coupled to the movable carriage along a length of the energy source. Each one of the plurality of shutters may be coupled to the movable carriage via respective coupling mechanism that provides a continuously variable movement of each one of the plurality of shutters.

Abstract: Drive belt systems and methods thereof are disclosed. Drive belt systems and methods thereof include driving a continuous belt around a drive pulley member and an idler pulley member by the drive pulley member and transporting a transport unit and/or reciprocating carriage unit coupled to the continuous belt in a first direction away from the drive pulley member. Drive belt systems and methods thereof also include applying at least a force to the belt in a traverse direction thereto to direct a portion of the belt about the drive pulley member by a belt stretch management apparatus coupled to the transport unit and/or reciprocating carriage unit.