Consumable scaffold for 3D printing of high-tensile-strength materials
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.
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, 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 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, and to make the trimmed distal end of the first pillar, the trimmed distal end of the second pillar, and the distal end of the third pillar not collinear;
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 when the trimmed distal end of the first pillar is heated;
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 when the trimmed distal end of the second pillar is heated; and
heating the distal end of the third pillar and a third part of the fiber-reinforced thermoplastic filament and fusing the third part of the fiber-reinforced thermoplastic filament to the distal end of the third pillar when the distal end of the third pillar is heated;
wherein the fiber-reinforced thermoplastic filament, when fused to the first and second pillars, spans a separation between the first and second pillars that is greater than the width of the second pillar and that is devoid of any pillars.
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. 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,
wherein the distal end of the first pillar, the distal end of the second pillar, and the distal end of the third pillar are collinear;
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 when the trimmed distal end of the first pillar is heated;
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 when the trimmed distal end of the second pillar is heated; 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 when the trimmed distal end of the third pillar is heated;
wherein the fiber-reinforced thermoplastic filament, when fused to the first and second pillars, spans a separation between the first and second pillars that is greater than the width of the second pillar and that is devoid of any pillars.
11. The method of claim 10 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.
12. The method of claim 10 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.
13. The method of claim 10 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.
14. The method of claim 10 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.
15. The method of claim 10 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.
16. The method of claim 10 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.
17. The method of claim 10 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.
18. The method of claim 17 wherein the material is polytetrafluoroethylene.