1. 3D printing workshop Introduction to 3D printing
Instructor: Chung Tsz Him

2. What is 3D printing?
2D printing means printing on a surface(2D), e.g. paper printer
3D printing means printing solid objects by adding materials layer by layer
Input a 3D-model
Printing by printer
Can use plastic, polymers, or even metal

3. History Actually not a new technology Charles Hull invented in 1984
Become popular in recent years
Due to advanced technology and lower cost

4. Pros & Cons Pros: Cons Fast prototyping Small size Lower costs
Less setup and wasted materials comparing to Molding(注塑成型), forging(鍛造) and casting(鑄造)
Cons
Small size
Few choices of materials
Slow printing

5. Technology Extrusion – Fused deposition modeling(FDM)
Heat and melt the materials first
Then “extrude” material layer by layer
Can use different kinds of materials (mostly plastic and clay)
Used by the 3D printer in the IT Clinic
Inexpensive BUT
Slow and not accurate

6. Light polymerized - Stereolithography
Laser shoot on liquid photopolymer
Liquid react with laser and become solid
Accurate and can print large object, BUT
Laser is dangerous and expensive

7. Powder Bed - Selective heat sintering (SHS) / Selective laser sintering (SLS)
Apply heat or laser on thermoplastic powder
Powder sinter (but not yet melt)
Very complicated and expensive

8. Powder Bed - Direct metal laser sintering (DMLS)
Similar to SLS
BUT used on metal
Powder Bed - Selective laser melting (SLM)
BUT will melt the metal powder
Can print very hard materials, e.g. Titanium alloys, stainless steel

9. Powder Bed - Powder bed and inkjet head 3D printing (3DP)
Similar to SLS
BUT use liquid binding material to combine the powder instead of laser
Faster than laser
BUT the powder may stick on the object

10. Laminated object manufacturing (LOM)
Use laser cuter to cut the adhesive-coated sheet of materials
Low cost
Can build large part BUT
Less accurate than SLS

11. Other technologies Robocasting or Direct Ink Writing (DIW)
Digital Light Processing (DLP)
Electron-beam melting (EBM)
Electron Beam Freeform Fabrication (EBF3)

12. 3D printer brands Makerbot (used in IT clinic) Movehand (a HK company)
Tiertime
Velleman

13. 3D modeling A 3d model file is STL file, e.g. ABC.stl
Can use Computer-aided design (CAD) or 3D modeling software to build
OR simply download from the internet!

14. Autodesk 3ds Max
Student can create account and download for free

15. OpenSCAD
Open sourced and free to use

16. Online resource Makerbot thingiverse: Youmagine
Youmagine