Abstract: Methods, particularly automated methods, are provided, as well as 3D-printed composite and hollow objects and 3D-printing systems for printing them. Methods comprise deriving a central line of a hollow 3D object model, calculating reference point(s) and/or line(s) along an inner surface of the hollow 3D object model, and filling the hollow 3D object model with material that comprises a thread defined with respect to the central line and the reference point(s) and/or line(s) and with filling material surrounding the thread. The support construction thus formed may be removed from the 3D object by pulling on the thread, extracting it and the surrounding support filling from the hollow object, thus enabling 3D-printing of convoluted or elongated hollow objects and objects with narrow openings. The parameters of the thread, such as type of curve and thickness, are selected to ensure thread extraction without risk of tearing or knotting the thread.

Abstract: A method of additive manufacturing of three-dimensional objects by sequentially dispensing and solidifying layers. The layers may include (i) stacks of model layers arranged in configured patterns corresponding to shapes of one or more objects and being made of one or more modeling materials; (ii) an intermediate layer surrounding said shapes of one or more objects and comprising at least a support material, and (iii) a flexible overlay surrounding said first intermediate layer, the intermediate layer and flexible overlay forming a flexible sacrificial structure. The model stack or stacks can be removed from the flexible sacrificial structure by application of pressure to the flexible sacrificial structure, separating the model stack from the flexible structure along the intermediate layer.

Abstract: A method of additive manufacturing of a three-dimensional object. The method comprises: sequentially dispensing and solidifying a plurality of layers comprising (i) a stack of model layers arranged in a configured pattern corresponding to the shape of the object and being made of a modeling material, (ii) a sacrificial structure having a stack of sacrificial layers made of an elastomeric material, and (iii) a stack of intermediate layers made of a support material having an elastic modulus less than the elastomeric material and being between the stack of model layers and the sacrificial structure; and applying a peeling force to the sacrificial structure to remove the sacrificial structure, and to expose the stack of model layers and/or the stack of intermediate layers beneath the sacrificial structure.

Abstract: A method of additive manufacturing of a three-dimensional object. The method comprises: sequentially dispensing and solidifying a plurality of layers comprising (i) a stack of model layers arranged in a configured pattern corresponding to the shape of the object and being made of a modeling material, (ii) a sacrificial structure having a stack of sacrificial layers made of an elastomeric material, and (iii) a stack of intermediate layers made of a support material having an elastic modulus less than the elastomeric material and being between the stack of model layers and the sacrificial structure; and applying a peeling force to the sacrificial structure (e.g., in dry environment) to remove the sacrificial structure, and to expose the stack of model layers and/or the stack of intermediate layers beneath the sacrificial structure.

Abstract: A waste curing device to cure waste generated by an additive manufacturing system, the waste curing device comprising: a container for receiving the waste; a movable cover positioned above the container; one or more waste nozzles mounted on the moveable cover and configured to deliver waste into the container; a static cover positioned above the container and below the movable cover; one or more curing sources mounted on the static cover and configured to provide curing radiation to cure the waste in the container; wherein the movable cover is configured to move relative to the static cover to provide an open position for the waste nozzles to deliver waste into the container, and subsequently to a closed position, to shield the waste nozzles from curing radiation.

Abstract: A waste curing device to cure waste generated by an additive manufacturing system, the waste curing device comprising: a container for receiving the waste; a movable cover positioned above the container; one or more waste nozzles mounted on the moveable cover and configured to deliver waste into the container; a static cover positioned above the container and below the movable cover; one or more curing sources mounted on the static cover and configured to provide curing radiation to cure the waste in the container; wherein the movable cover is configured to move relative to the static cover to provide an open position for the waste nozzles to deliver waste into the container, and subsequently to a closed position, to shield the waste nozzles from curing radiation.

Abstract: A method of additive manufacturing of three-dimensional objects by sequentially dispensing and solidifying layers. The layers may include (i) stacks of model layers arranged in configured patterns corresponding to shapes of one or more objects and being made of one or more modeling materials; (ii) an intermediate layer surrounding said shapes of one or more objects and comprising at least a support material, and (iii) a flexible overlay surrounding said first intermediate layer, the intermediate layer and flexible overlay forming a flexible sacrificial structure. The model stack or stacks can be removed from the flexible sacrificial structure by application of pressure to the flexible sacrificial structure, separating the model stack from the flexible structure along the intermediate layer.

Abstract: Methods, particularly automated methods, are provided, as well as 3D-printed composite and hollow objects and 3D-printing systems for printing them. Methods comprise deriving a central line of a hollow 3D object model, calculating reference point(s) and/or line(s) along an inner surface of the hollow 3D object model, and filling the hollow 3D object model with material that comprises a thread defined with respect to the central line and the reference point(s) and/or line(s) and with filling material surrounding the thread. The support construction thus formed may be removed from the 3D object by pulling on the thread, extracting it and the surrounding support filling from the hollow object, thus enabling 3D-printing of convoluted or elongated hollow objects and objects with narrow openings. The parameters of the thread, such as type of curve and thickness, are selected to ensure thread extraction without risk of tearing or knotting the thread.

Abstract: A waste curing device to cure waste generated by an additive manufacturing system, the waste curing device comprising: a container for receiving the waste; a movable cover positioned above the container; one or more waste nozzles mounted on the moveable cover and configured to deliver waste into the container; a static cover positioned above the container and below the movable cover; one or more curing sources mounted on the static cover and configured to provide curing radiation to cure the waste in the container; wherein the movable cover is configured to move relative to the static cover to provide an open position for the waste nozzles to deliver waste into the container, and subsequently to a closed position, to shield the waste nozzles from curing radiation.

Abstract: A method of 3D printing to achieve a desired surface quality on at least one surface of a 3D printed object comprising selecting a base surface having the desired surface quality; and printing the 3D printed object on the base surface, so that the desired surface quality is imparted to one surface of the 3D printed object during printing. The surface quality may be glassiness, roughness, smoothness and texture in general. Objects may thus be manufactured in which electronic components are integrated in or under a glass-like surface.

Abstract: A method of additive manufacturing of a three-dimensional object. The method comprises: sequentially dispensing and solidifying a plurality of layers comprising (i) a stack of model layers arranged in a configured pattern corresponding to the shape of the object and being made of a modeling material, (ii) a sacrificial structure having a stack of sacrificial layers made of an elastomeric material, and (iii) a stack of intermediate layers made of a support material having an elastic modulus less than the elastomeric material and being between the stack of model layers and the sacrificial structure; and applying a peeling force to the sacrificial structure (e.g., in dry environment) to remove the sacrificial structure, and to expose the stack of model layers and/or the stack of intermediate layers beneath the sacrificial structure.