The Joys of Hobby 3D Printing Well… It's usually joyful….
What We're Going to Cover Today ●
What is a 3D printer, and how do they work?
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A brief history of hobby 3D printing
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Should you get one, and what are they capable of?
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What are the process, tools, and components?
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What are the drawbacks?
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We'll print something!
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Q&A
What is a 3D printer? 3D Printer: ●
A device that performs “additive manufacturing” –
We will talk about this next
Act of 3D Printing: ●
With software tooling, take a 3D model and make it real –
This will get covered later in the presentation
Traditional Manufacturing is “Subtractive” ●
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Take a chunk of something and whittle it down to final shape A staple of any machine shop, there are many types: –
2D ● ●
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CNC laser/water-jet/plasma cutters CNC mill/router/press/lathe
3D ● ●
Multi-axis versions of the mill or router EDM (Electrical Discharge Machining)
So Additive Manufacturing Means? ●
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3D model of an object is horizontally subdivided into many single layers (a process we will later cover) Tool successively stacks thin layers of material to eventually create the complete object
OK, So How Do These Things Work? ●
Many different techs are employed by these machines
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The pros/cons of these techs vary wildly, including: –
Printable material (plastic, metal, cheese)
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Accuracy
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Minimum feature size
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Speed
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Part design limitations (this is key for hobby printers!)
Lets Cover Some of the Tech! ●
Lets briefly touch on the space-age tech that makes this possible! –
Vat Photopolymerization
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Material Jetting
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Binder Jetting
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Material Extrusion (a.k.a. Fused Deposition Modeling)
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Power Bed Fusion
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Sheet Lamination
Vat Photopolymerization ●
Starts with a tub of resin that is UV cured
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Layer by layer, tub is shot with a laser and lowered
Material Jetting ●
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Think of it like an extreme ink-jet printer Machine alternates between nozzles spraying material, and print lowering
Binder Jetting ●
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Even layer of powder is distributed With powder layer down jet nozzles glue the powder together
Material Extrusion (Fused Deposition Modeling) ●
Most hobbyist-grade machines work like this
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Roll of cold filament is fed into a heated extruder
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Nozzle at the end of the heated extruder then directs the plastic onto build
Power Bed Fusion (Selective Laser Sintering) ●
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like binder jetting, a powder layer is distributed. Unlike binder jetting, a laser does the powder-to-object conversion via sintering (no melting)
Sheet Lamination ●
Quasi-additive
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Typically metal foil, but paper is also used (for full color!)
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Puts down a sheet layer of material, ultrasonically welds it, then mills just that layer
Directed Energy Deposition ●
Essentially, CNC Laser welding
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Primarily metal print material
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Multi-axis robotic arm depoits metal filament or powder onto surface fuses the powder into place via: –
Laser
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Electron Beam
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Plasma
What Does Additive Manufacturing Offer Over Traditional Methods? ●
Low material waste
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Fast iteration cycles
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Low cost
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Unreal part complexity
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Toolchain actually simplifies things
Wow, This Sounds Really Fancy and New! ●
Not Really… –
1984 - Charles Hull developed the technology for printing physical 3D objects from digital data obtained patent for it in 1986 calling it “Stereolithography” 1988 - Scott Crump invented Fused Deposition Modeling (FDM) ●
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founded Stratasys on FDM tech in 1989
So The Conditions are Right. Now What? ●
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A little time & competition led to an industry –
Design simplifications
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Process and material improvements
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Cost reduction of the equipment
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This all led to hobbyist interest
2008 - An open source project - Reprap – is created, aimed at developing a self-replicating 3D printer. Could print 50% of its own parts by end of 2008. 2011 December, Printrbot was the most successfully funded Kickstarter in history (up until April 2012)
A Vibrant Hobbyist Industry is Born!!! ●
A hobbyists interest is sparked. They then: –
Evolved and improved the tech for regular users
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Developed software and tooling for normal folk
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Created an industry around it
Now you can get a competent 3D Printer for under $500
OK, Should I Get One?
Let's see what they can do first! (cue to finally show people something interesting)
Applications and Examples Around the house
Applications and Examples
Applications and Examples
Applications and Examples
Applications and Examples
These Are Capable Devices ●
Applications are nearly unlimited. –
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If you buy plastic stuff, Why!?
Materials are shockingly capable –
PLA and ABS are very capable for general use
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Exotics such as Nylon, fiber reinforced, elastic are showing up, further expanding what is possible
Full customization is now possible, in a hurry –
No longer confined to what's at Wal-Mart
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You can make your exact need, often in minutes
Cheap enough to afford many many iterations –
I just got 0.5kg for $11, and bigger designs use only 40g-70g
So How Do They Work? ●
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There is a sequence of steps needed to make a print happen, with specific tools for each part: –
Design using a design tool to make the 3D model
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Convert to Gcode using a slicer tool
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Print using a capable printer to turn Gcode into a blob
People often circumvent the 1st, rarely circumvent the 2nd
– Sites like youmagine and thingiverse have pre-made designs so you don't have to
Design Tool ●
Design tool selection is not a critical element
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Anything that can produce an .STL file –
AutoCAD Fusion360 is popular
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SolidWorks
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ProEngineer
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Many, many, more
Design Considerations ●
Design the part, keep in mind the limits of the tech –
Gravity
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Feature size
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Bed adhesion
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Part orientation
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Material
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Dumb slicer compensation
Design Considerations (cont'd) ●
Examples:
Slicer ●
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The slicer is really where the magic happens –
All the specifics of how your model is turned into print instructions lies here
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Like a compiler for a specific processor, this “Gcode compiler” should have innate knowledge of the target printer, or your print will look like the 1st slide
Virtually all of my encountered problems were corrected in the slicer. Not on the printer!
Slicer (cont'd)
Slicer (cont'd) There are many key controls located in this tool! ●
Infill: controls how much of the inside is actually extruded plastic vs. air, controls strength and cost
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Speed: affects cool rate, accuracy, bond strength, etc
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Temperatures: know your printer, filament, and model!
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Support structures: for difficult prints, bed adhesion and overhangs will need a helping hand
How About That Capable Printer? ●
Sure there's a lot of stuff there, but what actually matters? –
Extruder(s)
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Stepper motors
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Controller board
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Print surface
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Filament
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A rigid frame!
Extruder (a.k.a Hot End) ●
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Purpose of this component is to transition filament from solid to liquid stage To perform this critical task it: –
has a heating element
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a temperature sensor
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sometimes a cooling fan
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nozzle (limits feature size)
Stepper Motors ●
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At minimum there will be 4 of these, 3 for axis, 1 for extruder Gives us our precise control of movement to achieve accurate results Alternates electromagnet coils to very slowly and precisely rotate the shaft of the motor
Controller Board ●
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Translates Gcode commands from PC/SD to stepper movement Controls the extruder and bed temperatures
Print Surface (a.k.a. bed) ●
Flatness is key to good 1st layer –
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Some are heated, which helps with curling effects –
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A good 1st layer is critical to a successful print
With ABS printing, this is generally a requirement
A well cleaned/treated bed keeps part from moving –
Good adhesion makes or breaks a print
Rigid Frame ●
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A sufficiently rigid frame is crucial to good printing The best parts in the world on a frame made of duct tape will still yield atrocious results The rigidity required can be flexible, depending on the level of detail and print accuracy that you desire
What Are the Drawbacks of the Hobby? ●
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These are still far from mainstream ready –
For tinkerers, this poses no problem
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However, for people who want to just make stuff, this can be a frustrating hobby
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Very little standardization in the actual implementation of the tools
Tools are still rudimentary and young –
They are made by hobbyists for hobbyists
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Bugs, too many controls, conflicting controls
This is art, not science –
A healthy dose of “cross your fingers” goes a long way
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Sometimes the answer simply makes no sense
Demo and Q&A
Finally he shuts up and makes something!
