Electrostatic 3-D printer using layer and mechanical planer

A three-dimensional (3-D) printer comprising:

• an intermediate transfer surface;
• a build material development station positioned to transfer build material to said intermediate transfer surface;
• a support material development station positioned to transfer support material to said intermediate transfer surface, said build material development station and said support material development station transfer layers of said build material and said support material to said intermediate transfer surface;
• a platen having a flat surface positioned to contact said intermediate transfer surface, said intermediate transfer surface transfers a layer of said build material and said support material to said platen, or existing layers on said platen, each time said platen, or said existing layers, contact said intermediate transfer surface;
• a sensor detecting the thickness of said layer on said platen;
• a mechanical planer positioned to contact and level said layer on said platen as said platen moves past said mechanical planer, wherein said sensor is positioned between said mechanical planer and a location where said platen contacts said intermediate transfer surface;
• and
• a feedback loop electrically connected to said sensor and said mechanical planer, said mechanical planer moves toward and away from said platen to adjust the amount of material removed from said layer based on said thickness of said layer on said platen, as determined by said sensor.

A three-dimensional (3-D) printer comprising:

• an intermediate transfer surface;
• a build material development station positioned to transfer build material to said intermediate transfer surface;
• a support material development station positioned to transfer support material to said intermediate transfer surface, said build material development station and said support material development station transfer layers of said build material and said support material to said intermediate transfer surface;
• a platen having a flat surface positioned to contact said intermediate transfer surface, said intermediate transfer surface transfers a layer of said build material and said support material to said platen, or existing layers on said platen, each time said platen, or said existing layers, contact said intermediate transfer surface;
• a sensor detecting the thickness of said layer on said platen;
• a mechanical planer positioned to contact and level said layer on said platen by removing material from said layer as said platen moves past said mechanical planer, wherein said sensor is positioned between said mechanical planer and a location where said platen contacts said intermediate transfer surface;
• and
• a feedback loop electrically connected to said sensor and said mechanical planer, said mechanical planer moves toward and away from said platen to adjust the amount of material removed from said layer based on said thickness of said layer on said platen, as determined by said sensor.