Advanced Digital Fabrication

ADVANCED DIGITAL FABRICATION AND PROCESSES

Tristan Nethercott

1 VASE, INFILL & GRADIENTS 2 3D PRINTED ASSEMBLIES

1

Module 1 Vase, Infill & Gradients

1

VASE

| 001

| 6

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

VASE MODE PRINTING

FIGURE 1 DESCRIPTION The main issues with this print were having to do with the cantilevered sections. Horizontal gaps appear at the steepest angles which disrupts the prints air-tightness. A wider print width would possibly solve this issue for future prints. The bed adhesion was solid and the print bed pull required no clean-up.

Rhino Steps

Prusa Steps

Create circular curve at Z-0 Draw vertical line from the base Copy base curve along vertical Manipulate copies for varied shapes Loft curves into surface Cap the open surface Export STL file

Import STL file Choose type “vase” Select “spiral vase” Add “raft” and “brim” Slice form Analyze issues Export G-Code Print

1_ Rhino Closed Mesh 2_ PRUSA Tool Path 3_ Physical Print

| TRISTAN NETHERCOTT

| 7

| ADVANCED DIGITAL FABRICATION & PROCESSES

PRUSA i3 MK3 Print Process

FIGURE 4

4_ Cantilever issues 5_ Solid bed adhesion 6_ Cantilever issues

FIGURE 5

FIGURE 6

1

WALL

| 002

| 8

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

WALL WITH INFILL MODE

FIGURE 1 DESCRIPTION The main issues with this print were having to do with bed adhesion. The pull from the print bed was quite messy and the excess filament hairs from the raft created stability issues at the base. The gyroid infill pattern (25%) was discontinuous because of the tight wall confounds but the print was still structurally stable. For lighter and faster print, reduce infill percentage.

Rhino Steps

Prusa Steps

Create curve Add control points to curve Manipulate curve to undulate Extrude curve into closed surface Export STL file

Import STL file Choose “infill style” Manipulate infill % Add “raft” Remove “brim” Reduce “top layer” to 0 Export G-Code Print

1_ Rhino Closed Mesh 2_ PRUSA Tool Path 3_ Physical Print

| TRISTAN NETHERCOTT

| 9

| ADVANCED DIGITAL FABRICATION & PROCESSES

PRUSA i3 MK3 Print Process

FIGURE 4

4_ Discontinuous fill pattern 5_ Poor bed adhesion 6_ Stringy base layers

FIGURE 5

FIGURE 6

1

INFILL

| 003

INFILL WITHOUT WALL MODE

FIGURE 1

| 10

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

DESCRIPTION An identical footprint with a reduced infill percentage (15%) compared to the “walled” infill was used to compare results. The gyroid pattern was even more discontinuous than the previous one, but the print was remarkably stable still. This was surprising given the jumpy nature of this print that picked up and started sporadically. Much cleaner bed pull compared to the previous as well.

Rhino Steps

Prusa Steps

Create curve Add control points to curve Manipulate curve to undulate Extrude curve into closed surface Export STL file

Import STL file “Vertical shells” -> 0 “Horizontal shells” -> 0 Manipulate infill % Manipulate infill anchor “Fill angle” -> 0 “Auto generate supports” Export G-Code Print

1_ Rhino Closed Mesh 2_ PRUSA Tool Path 3_ Physical Print

| TRISTAN NETHERCOTT

| 11

| ADVANCED DIGITAL FABRICATION & PROCESSES

PRUSA i3 MK3 Print Process

FIGURE 4

4_ Discontinuous fill pattern 5_ Looser infill percentage 6_ Clean bed adhesion

FIGURE 5

FIGURE 6

1

GRADIENT PLA

| 004

| 12

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

POINT ATTRACTOR SCRIPT

FIGURE 1 DESCRIPTION The main issues with this print were in regards to bed adhesion and raft clean-up. Lowering the undulating form below the print bed allowed for a stable start, but it also created stringing issues. The print was very structurally stable due to its undulating form and it created a very interesting wood-grain pattern on the top of the print.

Rhino /Grasshopper Steps

Prusa Steps

Open Grasshopper script Adjust “brep” and “mesh” settings Choose point attractors Adjust output scale Adjust output thickness min/max Bake desired outcome Export STL

Import STL file Connect print to bed Add “raft” & “brim” Export G-Code Print

1_ Rhino Closed Mesh 2_ PRUSA Tool Path 3_ Physical Print

| TRISTAN NETHERCOTT

| 13

| ADVANCED DIGITAL FABRICATION & PROCESSES

PRUSA i3 MK3 Print Process

FIGURE 4

4_ Tricky base clean-up 5_ Wood grain pattern 6_ Stringy sides

FIGURE 5

FIGURE 6

1

GRADIENT FUSE

| 005

| 14

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

POINT ATTRACTOR SCRIPT

FIGURE 1 DESCRIPTION This print is identical to the previous, but it uses a different 3D printing technology (Formlabs Fuse). The process is known as ‘laser sintering’ and it is most applicable. The precision and strength of these prints allows for much wider application in sectors such as manufacturing and biomedicine.

Laser Sintering Process

Cleanup Process

Printer bed coated with powder Laser selectively heats powder Laser melts/fuses powder together Print bed lowers Process Repeats

Allow part to cool Remove from powder bed Move to vacuum booth Clean unused powder Apply surface finishing Reuse leftover powder

1_ Formlabs Fuse Physical Print 2_ Formlabs Fuse Physical Print 3_ Formlabs Fuse Physical Print

| TRISTAN NETHERCOTT

| 15

| ADVANCED DIGITAL FABRICATION & PROCESSES

Selective Laser Sintering Print Process

FIGURE 4

4_Laser Sintering 3D Formation 5_Vacuum Powder Cleaning 6_Finished Fuse Print

FIGURE 5

FIGURE 6

https://sinterit.com/blog/sls-technology/5-most-common-myths-about-sls-powder-handling/ https://www.buschvacuum.com/us/en/news-media/high-precision-3d-printing-with-metal-powder.html https://powder.samaterials.com/blog/the-application-of-3d-printing-tantalum-powder-in-biomedicine.html

2

MODULE 2 3D Printed Assemblies

2

INFILL

| 001

| 18

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

INTERLOCKING COMPONENTS

FIGURE 1 DESCRIPTION REGIONAL SCALE

A .3mm offset was utilized for this interlocking geometry print (.15mm/ curve) to begin to explore a locking mechanism. The fit was fairly flush, but for tighter fits, a .15mm offset would be preferable. It should also be noted that some issues arise with connections on the bed-side of the print due to slight overflow past the geometry boundary.

Rhino Steps

Prusa Steps

Produce interlocking curves Offset curves by .3mm Correct unintended offsets Extrude curves into closed surface Separate surfaces for print Export STL file

Import STL file Choose infill Style Rectangular Density 5% Export G-Code Print

1_ Rhino Closed Mesh 2_ PRUSA Tool Path 3_ Physical Print

| TRISTAN NETHERCOTT

| 19

| ADVANCED DIGITAL FABRICATION & PROCESSES

PRUSA i3 MK3 Print Process

FIGURE 4

4_ Rhino Offset Location 5_ Slight Gap In Tolerance 6_ Smooth Assembly Connections

FIGURE 5

FIGURE 6

2

INFILL

| 002

FIGURE 1

| 20

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

COMPONENT ASSEMBLY - KEY/LOCK

DESCRIPTION REGIONAL SCALE

Initially, a ‘key/lock’ component was planned for the final assembly print. This concept veered from the intended aggregation of a component so it was abandoned, but it provided plenty of insights into proper tolerance fits for the dowel connections of my ‘wall’ component assembly. The initial component test print was for an insert with lock pins, which utilized a .3mm offset. As can

be seen in Figure 1, the tolerance for this rounded .3mm connection was very loose, and would not be ideal for most applications. Due to this, the dowel connection for the ‘wall’ component was reduced to a .15mm offset and tested (Figure 2). This was still not ideal for the intended application so I reduced it once again to a .075mm offset for a snug fit. In addition to these tolerance

tests, a miniature assembly of the ‘wall’ components was printed (Figure 3). Although the scale reduced the connections to be nearly unusable, it provided a basic understanding of the different connection conditions throughout the ‘wall’ assembly.

1_ Component 1 Trial (.3 mm offset) 2_ Component 2 Trial (.15 mm offset) 3_ Component 2 Mini-Assembly

| TRISTAN NETHERCOTT

| 21

| ADVANCED DIGITAL FABRICATION & PROCESSES

Key/Lock Mechanism Design Process

FIGURE 4

4_ PRUSA Lock Pins/Insert Print 5_ Lock Pins - Unlocked State 6_ Lock Pins - Locked State

FIGURE 5

FIGURE 6

2

INFILL

| 003

FIGURE 1

| 22

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

COMPONENT ASSEMBLY - WALL

DESCRIPTION REGIONAL SCALE

A standard component, with vertical and horizontal connections, was the first to be printed. This print was oriented on its side, due to a reduced print time, but the filament direction for the finish pattern was not ideal with this print direction.

In the following prints, an upright position was maintained, and the finish and patterning of the components were much cleaner. In

addition to this improvement in surface finish, the upright print position also provided a different internal support pattern that can be seen when held up to the light. This difference in light-play and finish quality is something that needs to be considered at all scales, but at a larger architectural scale this is even more important, because the structure and load paths of the

components would differ.

Besides some slight issues with the cleanliness of bottom facing surfaces, the prints were successful and the automatically generated support forms were easy to clean.

What would be the ideal formation of these supports at an architectural scale to reduce material cost and cleaning labor?

1_ Standard Component 2_ Prusa Support Formation 3_ Incorrect/Inverted Tenon

| TRISTAN NETHERCOTT

| 23

| ADVANCED DIGITAL FABRICATION & PROCESSES

PRUSA i3 MK3 Print Process

FIGURE 4

4_ Comp. 2 Initial Design 5_ Comp. 2 Connection Design 6_ Corner Component Design

FIGURE 5

FIGURE 6

2

INFILL

| 003

FIGURE 1

| 24

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

COMPONENT ASSEMBLY - WALL

DESCRIPTION REGIONAL SCALE

The initial standard component that was printed had a mistakenly oriented tenon connection, Paying very close attention to connection orientation is crucial for successful assemblies. In addition, the sequencing of connections also must be carefully analyzed. For instance, the ‘mortise’ connections drop vertically into the ‘tenon’ channels and slide horizontally

within the channels to lock. The sequence of this connection is misaligned with the simpler ‘dowel’ connections. This is most evident in the corner components, where the geometry makes it impossible to complete both connections without flexing the components and likely breaking there male parts. In addition to improving the connection sequencing of

components, the structural integrity of them could also be improved by increasing the number of perimeter layers in the printer settings. 2 perimeter layers were used on the individual components, while 4 were used on the final assembly for this very reason.

1_ Vertical Connection 2_ Outside-Corner Connection 3_ Inside-Corner Connection

| TRISTAN NETHERCOTT

| 25

| ADVANCED DIGITAL FABRICATION & PROCESSES

PRUSA i3 MK3 Print Process

FIGURE 4

4_ Continued Shadow-Line Around Corner 5_ Corner Comp. - Infill 5% 6_ Corner Connection support formations

FIGURE 5

FIGURE 6

2

INFILL

| 002

FIGURE 1

| 26

| ADVANCED DIGITAL FABRICATION & PROCESSES

FIGURE 2

FIGURE 3

COMPONENT ASSEMBLY - WALL

DESCRIPTION REGIONAL SCALE

The final assembly aggregates the various components into a cohesive form at an architectural scale. 3 components stack upon each other to form a 5’ x 9’ x 1’ wall module. This module can then turn the corner both internally and externally, creating a cohesive wall form that has an infinite number of aggregation options and a high level of scalability. Ideally, the component

design at this scale would provide wall cavities within for a rainscreen and insulation layers. Beyond this building scale, the components can be scaled down to be used as enclosure cladding or even finish material such as backslash. One thing that should be considered is the size of the various connections at different scales. At the printed scales, the connections work well,

but at its largest ‘wall’ scale, these connections would become overly bulky and difficult to operate without heavy machinery. Ideally, these would be redesigned so that a small team of laborers could complete a small house assembly primarily by hand, in a similar fashion to framing a simple wall.

1_ Rhino Closed Mesh 2_ PRUSA Tool Path 3_ Physical Print

| TRISTAN NETHERCOTT

| 27

| ADVANCED DIGITAL FABRICATION & PROCESSES

PRUSA i3 MK3 Print Process

FIGURE 4

4_ Rhino “human-scale” options 5_ Prusa Print-Preview/Scale Decision 6_ Broken Connection - Increase Perimeter #

FIGURE 5

FIGURE 6