Abstract: A filament for use with a printer head of a 3D printer includes an exterior surface and an interior surface having color selectively applied thereto, where the color of the interior surface is visible through the exterior surface, and where the color is applied only to the interior surface such that the color remains substantially isolated from components of the printer head when traveling therethrough.

Abstract: A filament for use with a printer head of a 3D printer includes an exterior surface and an interior surface having color selectively applied thereto, where the color of the interior surface is visible through the exterior surface, and where the color is applied only to the interior surface such that the color remains substantially isolated from components of the printer head when traveling therethrough.

Abstract: A three-dimensional printer effects color changes in an extrudate using a color-application unit applying a colorant to the interior of a filament before it is melted within an extruder. Specifically, the color-application unit may receive a filament (or portions thereof) having an exposed interior surface, where color applicators are actuated to apply one or more colors to the interior surface of the filament in order to modify the extruded color. The filament may then be coupled, collapsed, or otherwise closed about the interior surface, e.g., by a mechanical coupler, to substantially enclose the interior surface of the filament, which is then fed to the extruder for fabricating a colored object in a three-dimensional fabrication process. By enclosing the colored surface within the filament before melting for extrusion, transition effects of a color change can be mitigated and transition time for a substantially complete change in color can be significantly reduced.

Abstract: An assembly that is configured to be coupled to and communicate with a 3D printer having a printer head includes a color-application unit positioned upstream of the 3D printer. The color-application unit is configured to receive a filament and direct the filament to the printer head of the 3D printer. The assembly also includes a color applicator coupled to the color-application unit. The color applicator is operable to selectively apply color to an interior surface of the filament.

Abstract: A three-dimensional printer effects color changes in an extrudate using a color-application unit applying a colorant to the interior of a filament before it is melted within an extruder. Specifically, the color-application unit may receive a filament (or portions thereof) having an exposed interior surface, where color applicators are actuated to apply one or more colors to the interior surface of the filament in order to modify the extruded color. The filament may then be coupled, collapsed, or otherwise closed about the interior surface, e.g., by a mechanical coupler, to substantially enclose the interior surface of the filament, which is then fed to the extruder for fabricating a colored object in a three-dimensional fabrication process. By enclosing the colored surface within the filament before melting for extrusion, transition effects of a color change can be mitigated and transition time for a substantially complete change in color can be significantly reduced.

Abstract: A tool path for an extruder depositing build material to create a two-dimensional cross-section of a three-dimensional model of an object includes building all regions of the object's exterior surfaces having a first material characteristic (e.g., a first color), and then transitioning to another build material having a second material characteristic (e.g., a second color different than the first color) to build all regions of the object's exterior surfaces having the second material characteristic. The extruder may traverse between different exterior regions having the same material characteristic by using an optimized path directly connecting different exterior regions along interior portions of the object. In this manner, infill can be created while saving time and material. In an aspect, only when there is no path through the interior portions that directly connects different exterior regions having the same material characteristic will the extrusion of build material be paused.

Abstract: A three-dimensional printer effects color changes in an extrudate using a color-application unit applying a colorant to the interior of a filament before it is melted within an extruder. Specifically, the color-application unit may receive a filament (or portions thereof) having an exposed interior surface, where color applicators are actuated to apply one or more colors to the interior surface of the filament in order to modify the extruded color. The filament may then be coupled, collapsed, or otherwise closed about the interior surface, e.g., by a mechanical coupler, to substantially enclose the interior surface of the filament, which is then fed to the extruder for fabricating a colored object in a three-dimensional fabrication process. By enclosing the colored surface within the filament before melting for extrusion, transition effects of a color change can be mitigated and transition time for a substantially complete change in color can be significantly reduced.

Abstract: An assembly that is configured to be coupled to and communicate with a 3D printer having a printer head includes a color-application unit positioned upstream of the 3D printer. The color-application unit is configured to receive a filament and direct the filament to the printer head of the 3D printer. The assembly also includes a color applicator coupled to the color-application unit. The color applicator is operable to selectively apply color to an interior surface of the filament.