This disclosure describes multi-fluid kits for three-dimensional printing, three-dimensional printing kits, and methods of testing powder bed material for contamination. In one example, a multi-fluid kit for three-dimensional printing can include a fusing agent and a detector solution. The fusing agent can include water, an electromagnetic radiation absorber, and a first pigment reactant. The electromagnetic radiation absorber can absorb radiation energy and convert the radiation energy to heat. The detector solution can include water and a second pigment reactant. The second pigment reactant can be reactive with the first pigment reactant to form a

An additive manufacturing apparatus includes a stage configured to hold a component. A radiant energy device is operable to generate and project radiant energy toward the stage. An actuator is configured to change a relative position of the stage relative to the radiant energy device. A feed module is configured to support a feed roll of a resin support upstream of the stage about a feed mandrel. A first control device is operably coupled with the feed mandrel. A take-up module is configured to support a take-up roll of the resin support downstream of the stage about a take-up mandrel. A second control device is operably coupled with the take-up mandrel. A computing system is operably coupled with one or more sensors. The computing system is configured to provide commands to at least one of the first control device or the second control device to respectively rotate the first control device or the second control device to obtain a target tension on the resin support.

An additive manufacturing apparatus can include a stage configured to hold one or more cured layers of resin that form a component. A radiant energy device can be operable to generate and project radiant energy in a patterned image. An actuator can be configured to change a relative position of the stage relative to the radiant energy device. A reclamation system can be downstream of the stage and can be configured to remove at least a portion of the resin from a resin support. The reclamation system can include a first collection structure configured to accept a resin support therethrough along a resin support movement direction. A first scraper is positioned within the first collection structure. The first scraper has an elongation axis that is offset from the resin support movement direction by an offset angle that is less than 90 degrees.

An additive manufacturing apparatus can include a stage configured to hold one or more cured layers of resin that form a component. A radiant energy device can be operable to generate and project radiant energy in a patterned image. An actuator can be configured to change a relative position of the stage relative to the radiant energy device. A reclamation system can be downstream of the stage and can be configured to remove at least a portion of the resin from a resin support. The reclamation system can include a first collection structure configured to accept a resin support therethrough along a resin support movement direction. A first scraper is positioned within the first collection structure. The first scraper has an elongation axis that is offset from the resin support movement direction by an offset angle that is less than 90 degrees.

A reclamation system for an additive manufacturing apparatus can include a collection structure configured to remove at least a portion of the resin from a foil. A containment vessel can be configured to retain the resin removed from the foil. A drain can direct the resin from the containment vessel to a reservoir.

A reclamation system for an additive manufacturing apparatus can include a collection structure configured to remove at least a portion of the resin from a foil. A containment vessel can be configured to retain the resin removed from the foil. A drain can direct the resin from the containment vessel to a reservoir.

An apparatus for removing powder from a powder-based additively manufactured part includes a chamber for locating a powder-based additively manufactured part therein, a support mesh for supporting a powder cake that includes one or more parts therein, an inlet for introducing a gas into the chamber to flow throughout the powder cake and fluidise the powder to disengage from the part, and an outlet to allow the gas to exit the chamber. The apparatus further includes a cryogenic blasting system for spraying a mixture of liquid CO.sub.2 and compressed air at the powder-based additively manufactured part to remove powder therefrom.

Method and plant for recovery of a processed, powdered structural material in a plant for manufacturing a three-dimensional component by selective solidification of the structural material by a beam directed onto the structural material, in which, in a construction station which includes a process chamber, the component is manufactured on a substrate plate in a construction module by layered hardening of the structural material and/or in which, in an unpacking station which includes an unpacking chamber, the component manufactured in the construction module is removed from the construction module, and the processed, non-hardened structural material is removed from the component, in which the processed structural material is collected in a collecting device by a recovery device and provided for further feeding into the process chamber for manufacturing further components, wherein the recovery device includes at least one cartridge filled with the processed structural material collected in the application device.

A sieve system includes a sieve for screening material by selectively passing first particles and not passing second particles of the material based on respective dimensions of the particles relative to dimensions of screening apertures in the sieve. A holding container feeds material to the sieve and a fines container receives the first particles screened by the sieve. A first fines container load is measured at a first time, and a second fines container load is measured at a second time. A fines rate is determined by a rate of change of the fines container load based on the measured first and second fines container loads and the first and second times. An operating condition of the sieve system is based on the fines rate and may provide an indication that the operation of the sieve, another component, or the sieve system as a whole is acceptable or unacceptable.

A layer forming apparatus includes a loading unit including a stage onto which powder is supplied, a rotator that flattens the powder on the stage to form a powder layer, and circuitry. The circuitry causes the rotator to move in a first direction parallel to a surface of the stage and rotate while contacting the powder on the stage to form the powder layer. Further, the circuitry causes the rotator to move in a second direction opposite to the first direction and rotate while contacting surplus powder not on the stage.