1. From CADjs to 3-D Printing

2. Area & Volume g = cube(1); g.display(); g = cube(1);
g.displayTransparent();

3. Area & Volume
g = cube(1);

4. Area & Volume
g = cube(1).difference(cube(2,0.5,0.5));
g.display();

5. Area & Volume g1 = cube(1); g2 = cube(2,0.5,0.5); g1.display();

6. Area & Volume g = cylinder(1,2); g.display(); g = cylinder(1,2);
g.displayTransparent();

7. Area & Volume
g = cylinder(1,2);
g.display();

8. Can be edited in Notepad
Saving Code
e1 = cube(4,3,3);
e1 = e1.union(cylinder(1.5,3,32).rotateX(90).translate(-2,0,0));
e1 = e1.difference(cylinder(0.75,3.1,32).rotateX(90).translate(-2,0,0));
e1 = e1.difference(cube(3.5,3,0.75).translate(-2,0,0));
e1=e1.union(cylinder(0.5,2).rotateZ(90).translate(3,0,0));
e1.display();
Saves JavaScript Code
Can be edited in Notepad

9. Recovers the last JavaScript code executed
Code Recovery
Recovers the last JavaScript code executed

10. Saving STL Saves Object as .stl Should NOT BE edited g = cube(1);
g.display();
Saves Object as .stl
Should NOT BE edited

11. Save as *.stl file Check size of model 3d Printers ~ mm (typical)
g = cube(1).difference(cube(2,0.5,0.5));
g.display();
Check size of model
3d Printers ~ mm (typical)
Scale if necessary
Save stl

12. Scaling g = cube(1).difference(cube(2,0.5,0.5)); g.scale(10);
g.display();

13. Read STL file into 3D Printer Software
Every 3D printer comes with software to read .stl file

14. Import .stl file
XYZware window- import *.stl file

15. Load model

16. Resize to fit printer

17. View Your Model
view
rotate
scale

18. Print

19. 3-D Printing Boolean Operations

20. Boolean Subtraction
How would you make this object?

21. Boolean Subtraction g1 = cube(1); g2 = cube(1,0.5,0.5);
g2 = g2.translateZ(0.25);
g1.display();
g2.displayTransparent();
g1 = cube(1);
g2 = cube(1,0.5,0.5);
g2 = g2.translateZ(0.25);
g1 = g1.difference(g2);
g1.display();

22. Potential Problem Small computation errors can result in slivers!
Even $100K CAD systems suffer from this problem!

23. Easy Solution No slivers! Go past boundary on subtraction!
g1 = cube(1);
g2 = cube(1.2,0.5,0.6);
g2 = g2.translateZ(0.3);
g1.display();
g2.displayTransparent();
g1 = cube(1);
g2 = cube(1.2,0.5,0.6);
g2 = g2.translateZ(0.3);
g1 = g1.difference(g2);
g1.display();
No slivers!

24. Boolean Addition How to design? Approach:
Create two solids touching each other and union
g1 = cube(1);
g2 = cube(1,0.5,0.5);
g2 = g2.translateZ(0.75);
g1 = g1.union(g2);
g1.display();

25. Even $100K CAD systems suffer from this problem!
Boolean Addition
Problem!
Gap due to numerical error!
Even $100K CAD systems suffer from this problem!

26. Easy Solution
Overlap for union!
No gaps!

27. 3-D Printing Display and Saving

28. 3-D Printing Printer Limitations

29. Print Direction
Layer by layer
Oops!
Dripping!
Solution?
No ‘dripping’

30. Print Direction
Drip?
Solution?
Choose your print direction carefully!

31. Print Direction Pick the best orientation for Z axis!
Drips in all direction!
Printer will add support structures

32. Support Structures

33. Practical Aspects of 3D Printing
#1: Design part to avoid support structures
#2: Pick print direction with minimal support structures

34. Cost of 3D Printing What is the cost of printing? Plastic Metal
$10.00 ~ $ per cm^3
Low quality: $0.30 per cm^3
Medium quality: $2.00 per cm^3
Typical Lego Piece: $ Setup cost
High quality: $10.00 per cm^3

35. Practical Aspects of 3D Printing
#1 Design part to avoid support structures
#2 Pick print direction with minimal support structures
#3 Reduce material usage

36. Printing Resolution Coarse Medium Fine
Printers can be set at different resolution
Finer resolutions take more time & cost more!

37. Practical Aspects of 3D Printing
#1 Design part to avoid support structures
#2 Pick print direction with minimal support structures
#3 Reduce material usage
#4 Avoid thin regions