rapid prototyping new technologies for the classroom
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Rapid PrototypingRapid Prototyping
New Technologies for the New Technologies for the ClassroomClassroom
What is Rapid Prototyping?
� A set of processes that allows a concept or idea to be turned into a three-dimensional physical object, usually in a matter of hours or days, rather than weeks or months.
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weeks or months.
� A technology with wide applicability in product design, manufacturing, sales/marketing, advertising and education.
What is Rapid Prototyping?
� Unlike machining methods that are subtractive wherematerial is removed to produce the desired shape
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What is Rapid Prototyping?
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What is Rapid Prototyping?
� Rapid Prototyping processes are additive – objects are built from a 3-dimensional computer model in layers, built from a 3-dimensional computer model in layers, without molds, forms, or machining.
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Rapid Prototyping at MSOE?
� 1989 — began with an NSF grant application to partially fund the purchase of first SLA machine
� 1991 — formed RP Consortium with four charter members: Outboard Marine Corporation (now BRP), Kohler
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Outboard Marine Corporation (now BRP), Kohler Company, Snap-on Tools and Harley-Davidson
� 1994 to 2003 — purchased a LOM machine, an FDM unit, a DTM Sinterstation , an SLA-5000, and another FDM machine, the only university in the U.S. with all these capabilities
� 2008 — moved into a larger RP lab with a total of 10 machines utilizing 15 different materials
Who is the Rapid Prototyping Consortium?
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� Reduces engineering changes
� Costs increase as the design moves from concept to product:
Why does RP have value?
$1,000,000
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$1
$10
$100
$1,000
$10,000
$100,000
$1,000,000
Conceptual
Design
Detail Design Prototype Tooling Production Field Service
Fail early to succeed sooner.
What is common to all RP processes?
� Construct solid model on any CAD system.
� Translate model to a surface representation: .stl file format is common to all RP machines.
� Generate 2-D slices with path definitions using RP
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� Generate 2-D slices with path definitions using RP machine-specific or third-party software.
� Build object.
� Post-process the part.
� Provide the expected finish.
What are current RP processes?
� Stereolithography (SLA)Transparent/translucent parts with good surface finish
� Selective Laser Sintering (SLS)
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� Selective Laser Sintering (SLS)Good strength, thermal stability and chemical resistance
� Fused Deposition Modeling (FDM)Similar to injection-molded ABS, polycarbonate or sulfones
� 3-Dimensional Printing (3DP)Most are fast — great for concept evaluation
Stereolithography
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Stereolithography
1- laser
2- mirror
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2- mirror
3- positioning mechanism
4- liquid polymer with photoinitiator
5- part
Stereolithography
Minimal FinishingFinished and Lacquered
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Selective Laser Sintering
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Selective Laser Sintering
1- laser
2- mirror
3- roller
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3- roller
4- powder
5- powder chamber
6- process chamber
7- part
Selective Laser Sintering
Use of glass-filled SLS provides
higher stiffness (2-3X) with
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higher stiffness (2-3X) with
essentially the same surface finish
as unfilled nylon polyamide
Fused Deposition Modeling
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Fused Deposition Modeling
1- material spool
2- heated
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2- heated extrusion head
3- part
4- platform
Fused Deposition Modeling
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Polyphenylsulfone (PPSF)
Concept Modeling Machines (3DP)
� Known by various trade names
� Multi-Jet Modeling, PolyJet printing or generically as 3-Dimensional printing (3DP)
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3-Dimensional printing (3DP)
� Uses thermoplastic polymers (ABS), photopolymers (acrylates), starch or plaster
� Characterized by high production speed and ease of operation
Concept Modeling Machines
� Relatively low acquisition costs
� Operating costs can be higher than anticipated
Most have poor dimensional accuracy and mechanical
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� Most have poor dimensional accuracy and mechanical strength compared to other RP processes
3-Dimensional Printing (Z Corp®)
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Pros/Cons of Common RP Processes
Stereolithography Selective Laser Sintering
Fused Deposition Modeling
3-Dimensional Printing
Technology in widest use Widest range of available RP materials (including metals)
Relatively low cost systems Low acquisition costs; higher than expected material costs
Transparent/translucent parts with good surface
Multiple parts can be stacked within each build
Compatible with office environments
Most are fast — great for concept evaluation
Highest accuracy High strength with good thermal stability and chemical resistance
Similar properties to injection-molded ABS, polycarbonate or sulfones
Fair-to-poor strength and impact resistance
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Build volume as large as 20” x 20” x 23”
Build volume: 14.5” x 12.5” x 17.5”
Build volume: 16” x 14” x 16” Smaller build volumes: usually about 12” x 10” x 8” (varies)
Limited strength and flexibility for some resins
Can be used for tooling or direct manufacturing
Slower than competing RP processes
Easy to use and operate
Can be a slow process for thick-walled parts
Surface finish not as smooth as SLA parts
Poor surface finish due to large slice thickness
Relatively poor accuracy
Largest number of alternative materials and sources
High material and initial equipment costs
Porosity may be a concern Limited choice of materials
Not resistant to high temp or chemical exposure
Most complex machine of all RP processes
Lacks the strength of similar injection molded plastic part
Limited use as a functional prototype (except for Objet)
How does the PLTW partnership work?
� PLTW-Wisconsin will join the Consortium as of January 1, 2011 and will have a block of RP build hours
� Schools eligible to participate can send student part files on an as-needed basis
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� Schools eligible to participate can send student part files on an as-needed basis
� No need for paperwork or Purchase Orders
� Part files and cost quotes are exchanged electronically
� Turn-around time is typically 2-3 days after receipt of the approved part file
How does the PLTW partnership work?
� No charges for shipping of parts
� Teachers and students participating in the program can attend regular RPC meetings at no additional cost
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regular RPC meetings at no additional cost
� Teachers and students get access to MSOE research and technical assistance from RPC staff
� Contact Steve Salter, PTLW-Wisconsin Director, for more details on the program