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3D PrintingECE Lightning Lab

Resources

• SolidWorks– Design parts

• Tinkerine Suite– Free Download

• Objet Studio– Lab computers

• ece.ubc.ca/~leos– SolidWorks help– 3‐D Printing help

• Design guidelines• Tutorials / Examples• Documentation• FAQ

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Order Parts

• Link on Website to Tech Support Page & Fab Services

• 3D Printing

• Electrical Fabrication– PCB Printing

• Mechanical Fabrication– Waterjet Cutting

– Powder Coating

– Material Order

• Service Charges Only– Free material (within reason)

• Fe

• Al

• Plywood

– Square only

3D Printing

• Fused Deposition Modeling (FDM)– Extrusion printing– Plastic melted and extruded to create features layer by layer

• PLA (polylactic acid)• ABS (acrylonitrile butadiene styrene)

• Stereo‐LithogrAphy (Polyjet SLA)– Layers of photosensitive resin cured by light

• Laser• UV

• Selective Laser Sintering (SLS)– Layers of powder spread over part and sintered by laser– Metals

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Tinkerine (FDM)

Advantages

• Cheap printer– You have DIRECT access

• Cheap material– Single Material

– Adjustable % Infill

• Durable parts

• Control over Density (honeycomb)

• Short turn‐around time– Low resolution

– Print it yourself

Disadvantages

• Low Resolution

• Dangerous to free parts from bed

• Design Constraints– Wall angles

– Gap bridges

– Pseudo support material

– Minimum feature size

• Open Source Driver Software– Bugs

– Features

Objet (Polyjet SLA)

Advantages

• High Resolution

• Can make ANYTHING– Impossible to machine

– Very thin / fragile parts

– Working assemblies

– Overhangs

• Professional Driver Software– Reliable

– Repeatable

Disadvantages

• Expensive printer & material– No DIRECT access

– Build + Support

• Solid parts only

• Long turn‐around time– High resolution

– Must place order

• Brittle– Worse in Z‐direction

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Support Material

37g4 Hours

24g2½ Hours

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SolidWorks : Save as STL File

5 deg

Smallest Value

Assemblies

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Printing an Assembly in Parts

Delete

Delete

OptionallyDelete

Delete

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Cost : 28 grams (build + support)

28g / 2:27 hours17g / 2:27 hours

Print Orientation

Build: 39Support: 30Time: 4:16

Cost: 69 grams

Build: 31Support: 3Time: 4:59

Cost: 34 grams

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Hollow Parts

Lots of Support MaterialDifficult to Clean

Hollow Parts

Multiple PiecesAdd Pegs/Holes

Crazy GluePress Fit

Minimal Support MaterialEasy to Clean

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Design for PrintingAesthetic / Functional

Structural &FDM / Waterjet

Friendly

Fillet

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Section View

Section View

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InterferenceDetection

&ClearanceVerification

Specs in SolidWorks

• Min. feature width : – 1mm (flexible)– 2mm (sturdy)– 5mm OD (shaft)

• Assemblies– Min. joint gap : 0.2mm– Shaft  = 0.5mm : 0.25mm on each 

side

• Rotating joint with low backlash– Brass shaft / printed bore– Bore OD = Shaft OD + 0.1mm

• Press Fit– Male OD = Female OD– Chamfer male

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Caveats

• Large STL files– Spherical features– Small angle spec in STL generator– Max: 100MB

• Assemblies not easily freed– Large joint surface area– Coupled joints– Small (fragile) shafts– Interferences– Glossy welds

• Scrape off ALL support material• Do not print threads

– Use insert

• Holes can be expanded but not shrunk– Do not drill FDM beyond wall thickness– Polyjet is brittle and may break when drilled

• Pressing:– Do not hammer– Use vise or press– Chamfer shafts/holes

• Drilling:– High speed chuck– Advance drill VERY SLOWLY

Post‐Processing

• Delicate Parts:

– Ultra‐Sonic Bath in Machine Shop (40 min)

Water

Sodium Hydroxide(Lye)

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• Screws– Threaded inserts– Sheet metal / self‐tapping– Sex/barrel bolts

• Retaining Rings– Internal– External– E‐Clip– Cotter Pins

• Rivets• Crazy Glue

– Hole/stud

Fasteners