3D Printing Part One
by Garrett Mace
[email protected] @macegr
3D Printing Basics ●
3D Printing Technology
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Digilent's 3D printers
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Preparing models for printing
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Speed/quality/strength tradeoffs
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Avoiding common pitfalls
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Operating the 3D Printers
3D Printing Technology Something virtual...
...is now physical
OK...but how?! One big problem into many smaller problems 1. “Slice” the 3D model into 2D layers 2. Deposit material to make the 2D shape 3. Move up one layer and repeat 4. Profit 5. Keep profiting until your patents expire 6. Profit some more
I am complex with many layers, like a plastic octopus lasagna
Types of 3D Printing ●
SLA (Stereolithographic Apparatus) – – –
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Uses light to harden a liquid resin High resolution but harsh chemicals Many material types as long as it's a resin
SLS (Selective laser sintering) – – –
Melts powder with frickin “laser” beams Good resolution, powder can be messy Lots of material options including metals
Types of 3D Printing ●
PP (Plaster Powder Bed) – –
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Inkjet moistens layers of plaster powder Models are weak unless treated with hardener
FDM/FFF (Fused Deposition Modeling) – –
Extrudes melted plastic from a nozzle Low resolution but strong parts and the materials and technology is cheap
Digilent's FDM Printers 3D Touch
Replicator 2
Hobby FDM Printers Prusa i3
Printrbot Simple
Sources for Existing 3D Models ●
Thingiverse www.thingiverse.com
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Repables www.repables.com
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YouMagine www.youmagine.com
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GitHub
Preparing models for 3D Printing ●
3D Models are in STL file format
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STL is just a 3D cloud of triangles
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Very possible to have a bad STL
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Needs to be “watertight”
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All triangle edges must touch one other edge
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Back faces must point into the model
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But let's assume we have a known good model
Preparing a model for the 3D Touch
Preparing a model for the 3D Touch
Preparing a model for the 3D Touch
Preparing a model for the 3D Touch
Preparing a model for the 3D Touch
Preparing a model for the 3D Touch
Preparing a model for the 3D Touch
Preparing a model for the Makerbot
Preparing a model for the Makerbot
Preparing a model for the Makerbot
Speed/quality/strength tradeoffs ●
Thicker layers (0.20mm and up) – – –
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Faster to print Usually a stronger print Visible layers detract from appearance
Thinner layers (0.20mm and below) – – –
Much slower to print Can be weaker Very thin layers can greatly improve appearance
Common 3D Printing Pitfalls ●
It's better to see a problem before you start!
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Print bed adhesion – –
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Replace tape often and wipe with isopropyl If using glue stick, scrape off and re-apply often
Overhangs (printing in midair) – – –
Orient model in 3D printing software to minimize Remember to enable support if necessary! Design to avoid overhangs when possible
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Always be aware of layer direction
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Make sure STL file is watertight!
Orient to minimize support
Overhang Details Doesn't need support Needs support
Layer Direction Detail Stronger part
Weaker part
Operating the 3D Printers ●
Time for a field trip!
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For future reference: –
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MakerBot Manual: http://downloads.makerbot.com/replicator2/MakerB ot_Replicator2_user_manual.pdf 3D Touch Manual: http://downloads.alibre.com/BFBAXON2-155420214.pdf
