Consumable Scaffold with Trimmed Pillars for 3D Printing

Abstract

A consumable scaffold and technique for supporting an object while it is being manufactured is disclosed. The consumable scaffold comprises a base sheet and an array of pillars that are cantilevered from one side of the sheet. The consumable scaffold resembles a bed of nails. Each pillar in the array of pillars is trimmed to a desired length and the object is manufactured by fusing thermoplastic filaments to the tips of the pillars.

What is claimed is: 
     
         1 . A method comprising:
 fabricating a consumable scaffold that comprises:
 (i) a base sheet that comprises an obverse side and a reverse side, and 
 (ii) a first pillar that is cantilevered from the obverse side of the base sheet, wherein the first pillar comprises a proximal end at the obverse side of the base sheet and a distal end, and 
 (iii) a second pillar that is cantilevered from the obverse side of the base sheet, wherein the second pillar comprises a proximal end at the obverse side of the base sheet and a distal end; 
   trimming the distal end of the first pillar and the distal end of the second pillar by different amounts with respect to each other, resulting in a trimmed distal end of the first pillar and a trimmed distal end of the second pillar, respectively;   heating the trimmed distal end of the first pillar and a first part of a fiber-reinforced thermoplastic filament and fusing the first part of the fiber-reinforced thermoplastic filament to the trimmed distal end of the first pillar; and   heating the trimmed distal end of the second pillar and a second part of the fiber-reinforced thermoplastic filament and fusing the second part of the fiber-reinforced thermoplastic filament to the trimmed distal end of the second pillar.   
     
     
         2 . The method of  claim 1  further comprising:
 severing the trimmed distal end of the first pillar from the first part of the fiber-reinforced thermoplastic filament; and 
 severing the trimmed distal end of the second pillar from the second part of the fiber-reinforced thermoplastic filament. 
 
     
     
         3 . The method of  claim 1  wherein the first pillar is a cylindrical pillar and the step of trimming comprises trimming the distal end of the first pillar to form a frustum of a cone. 
     
     
         4 . The method of  claim 1  wherein the first pillar is a cruciate pillar and the step of trimming comprises trimming the distal end of the first pillar to form a frustum of a conic cruciate. 
     
     
         5 . The method of  claim 1  wherein the first pillar is an I-beam pillar and the step of trimming comprises trimming the distal end of the first pillar to form a frustum of a conic I-beam. 
     
     
         6 . The method of  claim 1  wherein at least a portion of the obverse side of the base sheet is characterized by a cross-section with a first contour; and
 wherein a cross-section of the first contour is convex. 
 
     
     
         7 . The method of  claim 1  wherein at least a portion of the obverse side of the base sheet is characterized by a cross-section with a first contour; and
 wherein a cross-section of the first contour is concave. 
 
     
     
         8 . The method of  claim 1  wherein the consumable scaffold is fabricated from molten thermoplastic, the method further comprising mechanically affixing the consumable scaffold to a build plate of a 3D printer, and wherein the build plate comprises a material that is phobic to the molten thermoplastic. 
     
     
         9 . The method of  claim 8  wherein the material is polytetrafluoroethylene. 
     
     
         10 . The method of  claim 1  wherein the consumable scaffold further comprises:
 (iv) a third pillar that is cantilevered from the obverse side of the base sheet, wherein the third pillar comprises a proximal end at the obverse side of the base sheet and a distal end; and 
 wherein the trimming of the distal end of the first pillar and the distal end of the second pillar ensures that the trimmed distal end of the first pillar, the trimmed distal end of the second pillar, and the distal end of the third pillar are not co-linear; and 
 further comprising heating the distal end of the third pillar and a third part of a fiber-reinforced thermoplastic filament and fusing the third part of the fiber-reinforced thermoplastic filament to the distal end of the third pillar. 
 
     
     
         11 . A method comprising:
 fabricating a consumable scaffold that comprises:
 (i) a base sheet that comprises an obverse side and a reverse side, and 
 (ii) a first pillar that is cantilevered from the obverse side of the base sheet, wherein the first pillar comprises a proximal end at the obverse side of the base sheet and a distal end, and 
 (iii) a second pillar that is cantilevered from the obverse side of the base sheet, wherein the second pillar comprises a proximal end at the obverse side of the base sheet and a distal end, and 
 (iv) a third pillar that is cantilevered from the obverse side of the base sheet, wherein the third pillar comprises a proximal end at the obverse side of the base sheet and a distal end; 
   trimming the distal end of the first pillar, the distal end of the second pillar, and the distal end of the third pillar by different amounts with respect to one another, resulting in a trimmed distal end of the first pillar, a trimmed distal end of the second pillar, and a trimmed distal end of the third pillar, respectively;   heating the trimmed distal end of the first pillar and a first part of a fiber-reinforced thermoplastic filament and fusing the first part of the fiber-reinforced thermoplastic filament to the trimmed distal end of the first pillar;   heating the trimmed distal end of the second pillar and a second part of the fiber-reinforced thermoplastic filament and fusing the second part of the fiber-reinforced thermoplastic filament to the trimmed distal end of the second pillar; and   heating the trimmed distal end of the third pillar and a third part of a fiber-reinforced thermoplastic filament and fusing the third part of the fiber-reinforced thermoplastic filament to the trimmed distal end of the third pillar.   
     
     
         12 . The method of  claim 11  further comprising:
 severing the trimmed distal end of the first pillar from the first part of the fiber-reinforced thermoplastic filament; 
 severing the trimmed distal end of the second pillar from the second part of the fiber-reinforced thermoplastic filament; and 
 severing the trimmed distal end of the third pillar from the third part of the fiber-reinforced thermoplastic filament. 
 
     
     
         13 . The method of  claim 11  wherein the first pillar is a cylindrical pillar and the step of trimming comprises trimming the distal end of the first pillar to form a frustum of a cone. 
     
     
         14 . The method of  claim 11  wherein the first pillar is a cruciate pillar and the step of trimming comprises trimming the distal end of the first pillar to form a frustum of a conic cruciate. 
     
     
         15 . The method of  claim 11  wherein the first pillar is an I-beam pillar and the step of trimming comprises trimming the distal end of the first pillar to form a frustum of a conic I-beam. 
     
     
         16 . The method of  claim 11  wherein at least a portion of the obverse side of the base sheet is characterized by a cross-section with a first contour; and
 wherein a cross-section of the first contour is convex. 
 
     
     
         17 . The method of  claim 11  wherein at least a portion of the obverse side of the base sheet is characterized by a cross-section with a first contour; and
 wherein a cross-section of the first contour is concave. 
 
     
     
         18 . The method of  claim 11  wherein the consumable scaffold is fabricated from molten thermoplastic, the method further comprising mechanically affixing the consumable scaffold to the build plate of a 3D printer, and wherein the build plate comprises a material that is phobic to the molten thermoplastic. 
     
     
         19 . The method of  claim 18  wherein the material is polytetrafluoroethylene. 
     
     
         20 . The method of  claim 11  wherein the trimming of the distal end of the first pillar, the distal end of the second pillar, and the distal end of the third pillar ensures that the trimmed distal end of the first pillar, the trimmed distal end of the second pillar, and the trimmed distal end of the third pillar are not co-linear.