nyu presentation
TRANSCRIPT
3D Printing Technologies, Rapid Prototyping, and 3D
Scanning PRINT3D @ NYUPresented to the students of NYU and Columbia by Walter Hans Jaeger
What will we discuss?
• Origins
• Printing Technologies
• Materials
• How it works
• Standards
• 3D Scanning
• The Future
All the cool kids are doing it!• The personal computer revolution
happened at clubs just like this, by students about your age.
• This is something you can positively make an impact on as a hobbyist.
“What the smartest people do on the weekend is what everyone else will do during the week in ten years” --Chris Dixon
“From the get go, I imagined that 3D printing would significantly change design and manufacturing as we know it, but I could not have anticipated the profound impact the technology would have on everything in our lives. It is both humbling and exhilarating to be apart of this incredible transformation.”
-- Chuck Hull
“If RepRap’s successful, a number of changes may well happen in society…
When they want something it’ll simply be a question of downloading it… no transport involved except for the raw materials, which have to be transported anyway of course, and thus we have short circuited a large part of the conventional supply chain for material goods to individuals.”
--Adrian Boyer
“Pretending you know what you’re doing is almost the same as knowing what you are doing, so just accept that you know what you’re doing even if you don’t and do it.”
-- Bre Pettis
History• The earliest 3D Printers were created in
the 80s as a method of rapid prototyping
• The print matrix / structure created was much worse than the cheapest printers today. Models would frequently fall apart.
• Before this, prototypes would have been milled – “Subtractive Manufacturing”
• 3D Printing was called then called “Additive Manufacturing”
3D Printing Technologies
• Stereolithography (SLA)
• Laser Sintering (SLS)
• Fused Deposition Modeling (FDM)
• Laminated Object Manufacturing (LOM)
Stereolithography
• Container of Liquid photopolymer resin
• Laser “cures” layers subsequently.
• The finished product is cured polymer.
Laser Sintering
• A powdered media of glass, plastic, or metal is used.
• Uses high-energy laser pulses.
• Typically does not need “support fills”
Fused Deposition Modeling
• New Method used by lower end printers.
• Materials are cheap and easy to find.
• Feeds filament through heated extruder.
Laminated Object Mfg.
• Uses sheets of material.
• Sheets are laminated to each other.
• Makes large scale objects possible.
Materials used in 3D Printing
• Plastics
• Elastomeric Plastic
• Alloyed Metals
• Frosted Glass
• Sandstone / Silica
• Wood / cellulose
• Sugar and Food Additives
Materials
When it comes to 3D printer material, there is no “best” material – only the right material for the project.
--3dmakers.com
Plastics
• Polylactic Acid (PLA)
• Acrylonitrile Butadiene Styrene (ABS)
• Polyamid (PLA)
• Polycarbonate (PLE)
• Liquid Polymer Resin
Alloyed Metals
• IN718 (Nickel)
• Cobalt – Chrome
• Aluminum
• Titanium
• Maraging Steels
• Virtually ANY alloy.
Frosted Glass
• Silica Powder or glass beads with a polymeric binder.
• Requires a furnace / kiln to bake away the binding agent.
• Usually Glazed afterwards for looks and long-term durability.
Sandstone and Cellulose
• Sandstone tends to be brittle, so it’s treated with cyanoacrylate (superglue) after printing.
• Wood Cellulose with a polymer binder. In the experimental stages, but shows promise.
Foods
• Fundamentally, printing corn starch (PLA), is not that different from printing sugar and starch.
• This makes 3D Printing an ideal candidate for making and decorating cakes, specially designed foods, etc.
How does it work?
• A 3D Model is converted into STL/OBJ
• That file is then “Sliced” into layers.
• Gcode is generated to print the design.
• The operator examines the Gcode.
• The 3D Printer prepares the medium.
• It then uses stepper motors to change object position until all layers are finished.
Hierarchy of Files
• 3D Drawing (Maya, Solidworks, 3D CAD)
• Exported to Standard Tessellation Language (STL – Portable)
• Sliced to Gcode (fairly machine specific)
What makes up a 3D Printer?
• Some kind of rigid frame / container.
• Moveable X,Y, and Z Axes.
• A supply of material.
• Either, an extruder (or) a curing laser.
• A flat surface for a printbed.
• A print controller board w/ stepper drivers.
• Embedded controls / hardware interface.
What is an extruder?
The Extruder is what “makes” the design, they consist of:
•A stepper controller that feeds filament
•A heated nozzle that maintains temperature to keep the filament material in a liquid state.
•Sensors (thermistors) that report back to the control board.
So how does it move?
• Belts, screws, or other methods may move the bed, the extruder, or both.
• 3D Printers may used software imposed limits, but hardware “endstops” are frequently used to simplify this.
Example:
goto x=0, y=0, z=0 (or)
x=max, y=max, z=max
What are some examples of commercial software?
• Autodesk Maya
• Rhinocerus 3D (Rhino)
• Pixologic Zbrush
• SolidWorks
• Z Corporation ZPrint
What are some examples of open source software?
• Blender
• Meshlab
• Archimedes
• Repetier Host
• ReplicatorG
Standards
• The only standards so far are for file formats:
STL: Stereolithography
OBJ: 3D Object
• There are no other standards yet, but a number of organizations are working on them.
3D Scanning
• Mesh Creation / Point Cloud
• Open Source – FabScan (DIY)
• Makerbot Digitizer
• Kinect (OSL + MSKDT)
How does 3D Scanning work?
• An object is put stationary in front of a camera and a synchronized laser (some systems use Infrared data too)
• The object is very slowly rotated 360 degrees sequentially, the slower it is scanning, the better the accuracy will be.
• The resulting scan will need to be cleaned up and turned into an STL file.
The Future
In five years, it is likely 3D Printing will be available in Big Box Hardware stores.
There will be a database to pull designs from, direct from the manufacturer.
Medical devices will take days, rather than weeks to manufacture.
Everything will be infinitely more customizeable, for a price that’s very small.