From CADjs to 3-D Printing

Area & Volume

g = cube(1);g.display();

Area?Volume?

g = cube(1);g.display();g.info();

Area & Volume

g = cube(1).difference(cube(2,0.5,0.5))

Area?Volume?

g.info();

Area & Volume

g = cylinder(1,2);

Area?Volume?

g.info();

g = cylinder(1,2,64).info();

Export as *.stl file

• Check size of model• 3d Printers ~ mm (typical)• Scale if necessary• Save stl

test.info();

test.scale(10);

test.saveSTL()

Open .stl file

Read STL file into 3D Printer Software

Every 3D printer comes with software to read .stl file

Import .stl file

XYZware window- import *.stl file

Load model

Resize to fit printer

View Your Model

A. view

B. rotate

C. rotate

D. scale

Print

3-D Printing

Boolean Operations

Boolean Subtraction

How would you make this object?

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();

Potential Problem

Sliver!

Small computation errors can result in slivers!

Easy Solution

g1 = cube(1);g2 = cube(1.2,0.5,0.6);g2 = g2.translateZ(0.3);g1.display();g2.displayTransparent();

Go past boundary on subtraction!

g1 = cube(1);g2 = cube(1.2,0.5,0.6);g2 = g2.translateZ(0.3);g1 = g1.difference(g2);g1.display();

No slivers possible!

Boolean Addition

Approach: Create two solids touching each other and union

How to design?

g1 = cube(1);g2 = cube(1,0.5,0.5);g2 = g2.translateZ(0.75);g1 = g1.union(g2);g1.display();

Boolean Addition

Problem!

Gap!

Easy Solution

Overlap for union!

No gaps possible!

3-D Printing

Display and Saving

Display

When printing your final project there must only be 1 display.

Find the display functions used.

Project=Person.union(Legs);

Project.display();

Union the objects used in your final project and display

*Reminder:

Multiple displays can be helpful for debugging, but must be removed when project is complete

Saving

Saving Code: Saving STL:(F1)

Only saves the text and can be edited in notpad

saveSTL()

Often the file is sent to the downloads folder

.stl files

SHOULD NOT be edited after saving

3-D Printing

Printer Limitations

Print Direction

Layer by layer

Oops!Dripping!

Solution?

No ‘dripping’

Print Direction

Drip?

Solution?

Choose your print direction carefully!

Print Direction

Direction?

Drips in all direction!

Pick any direction 3D Printer will add support structures

Support Structures

Practical Aspects of 3D Printing

#1: Design part to avoid support structures

#2: Pick print direction with minimal support structures

Cost of 3D Printing

What is the cost of printing?

Low quality: $0.30 per cm^3

Medium quality: $2.00 per cm^3

High quality: $10.00 per cm^3

Plastic Metal

$10.00 ~ $200.00 per cm^3

Typical Lego Piece: $2.00 + Setup cost

Practical Aspects of 3D Printing

#1 Design part to avoid support structures

#2 Pick print direction with minimal support structures

#3 Reduce material usage

Printing Resolution

Coarse Medium Fine

Printers can be set at different resolution

Finer resolutions take more time & cost more!

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