1. Designing for Rapid Prototyping
Computer Integrated Manufacturing
© 2013 Project Lead The Way, Inc.

2. Designing for Rapid Prototyping
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Designing for Rapid Prototyping
Rapid prototyping devices are valuable in a design process
Prototype
Final product
Understand RP equipment to improve a design
Design for strengths and weaknesses of RP equipment

3. Rapid Prototyping
A virtual model is sliced into thin sections like a stack of playing cards
Physical model is created one layer at a time from the base of the model
Fused Deposition Modeling
A method of rapid prototyping which deposits heated thermoplastic layer by layer to create a physical model from a virtual model

4. Fused Deposition Modeling
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Fused Deposition Modeling
Subsequent layers need support from layer immediately below
Support can be created
Support material from a second extruder
Low density pattern
Common thermoplastics used in Fused Deposition Modeling are:
ABS, Acrylonitrile Butadiene Styrene. Shrinks on cooling. Has higher strength than PLA.
PLA, Polylactic Acid. Less shrinkange than ABS. Lower strength than ABS.
PVA, Polyvinyl Alcohol. Water soluble plastic used as support material.
Support Material
Removed
Support Material

5. Fused Deposition Machine
Presentation Name
Civil Engineering and Architecture®
Unit # – Lesson #.# – Lesson Name
Fused Deposition Machine
General process:
A part is printed one layer at a time along the z-axis.
A plastic filament spool is mounted onto the device to supply material to an extruder.
An extruder draws filament from a spool as the device operates. There can be one spool or more than one spool depending on the device complexity.
A nozzle melts the plastic as the extruder feeds filament through the nozzle.
The extruder and nozzle is mounted so that it can be moved along the y-axis direction while the printer bed moves along the x-axis.
The nozzle deposit a thin bead of extruded plastic to form each layer.
The plastic hardens immediately after being squirted from the nozzle and bonds to the layer below.
The print bed moves down to the next layer to be deposited.

6. Fused Deposition Machine
Presentation Name
Civil Engineering and Architecture®
Unit # – Lesson #.# – Lesson Name
Fused Deposition Machine
General process:
A part is printed one layer at a time along the z-axis.
Multiple plastic filament spools are mounted onto the device to supply material to an extruder.
An extruder draws filament from its spool as the device operates. At least one spool will contain filament for the part and another spool contain support material.
A nozzle melts the plastic as the extruder feeds filament through the nozzle.
The extruder(s) and nozzle(s) is mounted so that it can be moved along the y-axis direction while the printer bed moves along the x-axis.
The nozzle(s) deposit(s) a thin bead of extruded plastic to form each layer.
The plastic hardens immediately after being squirted from the nozzle and bonds to the layer below.
The print bed moves down to the next layer to be deposited.

7. Fused Deposition Materials
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Fused Deposition Materials
Common thermoplastics
ABS, Acrylonitrile Butadiene Styrene
PLA, Polylactic Acid
PVA, Polyvinyl Alcohol
Common thermoplastics used in Fused Deposition Modeling are:
ABS, Acrylonitrile Butadiene Styrene. Shrinks on cooling. Requires a heated bed. Has higher strength than PLA.
PLA, Polylactic Acid. Less shrinkage than ABS. Does not require a heated bed. Lower strength than ABS.
PVA, Polyvinyl Alcohol. Water soluble plastic used as support material.

8. Fused Deposition Support
Vertical features provide support for subsequent layers
Part orientation can optimize support
No Support Needed
Support Might be Needed

9. Fused Deposition Support
Parts above void section often require support
Support Geometry
Low Density Pattern from Single Extruder

10. Fused Deposition Orientation
Optimize and orient to minimize support
Final Product
Optimal Print Orientation
Not Optimal Print Orientation

11. Fused Deposition Surface Finish
Post processing can impact surface quality
Orient model so finish is optimal
Rough
Unseen
Side
Finished
Side
To be
Shown
Orientation for
Production
Inverted for
Post-Production
Processing

12. Fused Deposition Infill
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Fused Deposition Infill
Infill geometry of a solid model selected in printer software not .ipt or .stl
Printing a ‘Solid’
.stl Model
Infill can be increased for improved part strength; however, this increases the printing time, print cost and part weight.

13. Designing for Rapid Prototyping
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Designing for Rapid Prototyping
ABS shrinkage
Design to compensate for shrinkage
ABS Shrinkage impacted by many factor such as
Printing temperature
Part geometry
ABS Quality
Part with a in. Difference in Width Along a Dimension

14. Fused Deposition Parts Joining
Parts can be joined using fasteners
Shrinkage Not Accounted for in Design
Rods Joining
Parts

15. Fused Deposition Part Usage
Printed Part Used as a
Wind Tunnel Model

16. Fused Deposition Part Verification
Verifying Fit of Cams to VEX Shaft
Verifying Accuracy
Verifying Fit of Adapter

17. References
Groover M. P. (2012). Introduction to manufacturing processes. Hoboken, NJ: John Wiley & Sons, Inc.