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+ Plastic is Forever
+ 45 Minutes: Tomu's Injection-Molded Case
+
+ Sean "xobs" Cross
+
+
+
+
+ [Image of Tomu]
+
+
+
+ [Image of Tomu Case]
+
+
+
+
+ Outline
+
+ - Manufacturing the Case
+ - Designing the Case
+ - Understanding Plastics
+
+
+
+
+ About Me
+
+ - Novena
+ - Tomu
+ - Fomu
+
+ Manufacturing is Fun!
+
+
+
+
+ Factory Tour!
+
+
+
+ Front Door
+ ![]()
+
+
+
+ Bags of Plastic Pellets
+ ![]()
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+
+
+ Inside the Bags
+ ![]()
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+
+
+ Into the Machine
+ ![]()
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+
+
+ Pulling a Shot
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+
+
+ Factory Mold Bases
+ ![]()
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+
+
+ Tomu on its Mold
+ ![]()
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+
+
+ Both Mold Halves
+ ![]()
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+
+
+ Bottom Half
+ ![]()
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+ Ejectors
+ ![]()
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+ Cases on Runners
+ ![]()
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+ Factory Edits
+ ![]()
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+ Tool Model
+ ![]()
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+ ![]()
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+ ![]()
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+ ![]()
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+
+ Designing the Case
+
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+
+ 3D Printing
+ Almost (but not quite) entirely unline injection molding
+
+ - STL vs STEP
+ - Overhangs
+ - Support structures
+ - Flow rate/lines
+ - Time taken
+ - Family molds
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+
+
+
+ Hardware
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+
+
+ Software: FreeCAD
+ ![FreeCAD Example]()
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+
+
+ FreeCAD can create STEP files
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+
+
+ FreeCAD can read KiCad files
+ ![KiCad PCB inside FreeCAD]()
+
+
+
+ 1) Open the PCB
+ ![First, open the PCB in FreeCAD]()
+
+
+
+ 1) Open the PCB
+ ![Click 'Create Sketch']()
+
+
+
+ 2) Create a sketch
+ ![Creating constraints on the first sketch]()
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+
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+ 2) Create a sketch
+ ![Creating constraints on the first sketch]()
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+ 2) Create a sketch
+ ![Creating constraints on the first sketch]()
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+ 2) Create a sketch
+ ![Creating constraints on the first sketch]()
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+ 2) Create a sketch
+ ![Sketch done, starting pad]()
+
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+ 3) Pad the sketch
+ ![Done with the pad]()
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+ 3) Pad the sketch
+ ![Done with the pad]()
+
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+
+ 3) Pad the sketch
+ ![Pad at an angle]()
+
+
+
+ 4) Repeat as necessary
+ ![Create sketch for pocket]()
+
+
+
+ 4) Repeat as necessary
+ ![Complete sketch for pocket]()
+
+
+
+ 4) Repeat as necessary
+ ![Create a pocket]()
+
+
+
+ 4) Repeat as necessary
+ ![Create a pocket]()
+
+
+
+ 4) Repeat as necessary
+ ![Create a pocket]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Click on face for sketch]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Pocket with no PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Creating a pad for the alignment bump]()
+
+
+
+ 4) Repeat as necessary
+ ![Creating the sketch for the guiding slots]()
+
+
+
+ 4) Repeat as necessary
+ ![Finished case without PCB]()
+
+
+
+ 4) Repeat as necessary
+ ![Finished case with PCB]()
+
+
+
+ 5) Check with reference parts
+ ![Test with models]()
+
+
+
+ Here's what we sent to the factory
+ ![STEP model we sent to factory]()
+
+
+
+ And here's what they sent back
+
+
+
+
+
+
+ Real World Fun
+ And the problems you'll face
+
+
+
+ Clothes peg
+
+
+
+ Aircon Remote (Back)
+
+
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+ Aircon Remote (Front Cover)
+
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+
+ Wine bottle opener
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+ iPhone 3G
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