TYPES OF RAPID PROTOTYPING

2. FUNDAMENTALS
OF RP
TYPES OF RP
SLAFDM
SLS 3D PRINTER

3. INPUT, METHOD, MATERIAL,
APPLICATION

4. Figure 2.1: The Rapid Prototyping Wheel depicting
the 4 major aspects of RP

5.  Input refers to the electronic information required
to describe the physical object with 3D data.
 There are two possible starting points – a
computer model or a physical model.
 The computer model created by a CAD system
can be either a surface model or a solid model.

6.  On the other hand, 3D data from the physical
model is not at all straightforward.
 It requires data acquisition through a method
known as reverse engineering.
 In reverse engineering, a wide range of equipment
digitizer, to capture data points of the physical
model and “reconstruct” it in CAD system.

7.  While they are currently more than 20
vendors for RP systems, the method
employed by each vendor can be generally
classified into the following categories:
◦ photo-curing,
◦ cutting and glueing/joining,
◦ melting and solidifying/fusing and joining/binding.

8.  Photo-curing can be further divided
into categories of
◦ single laser beam,
◦ double laser beams and
◦ masked lamp

9.  The initial state of material can come in either
◦ solid, liquid or powder state.
 In solid state, it can come in various forms
such
◦ a pallets, wire or laminates.
 The current range materials include
◦ paper, nylon, wax, resins, metals and ceramics.

10.  Most of the RP parts are finished or
touched up before they are used for
their intended applications.
 Applications can be grouped into:
◦ Design
◦ Engineering, Analysis and Planning
◦ Tooling and Manufacturing

11.  A wide range of industries can benefit
from RP and these include, but are
not limited to,
◦ aerospace,
◦ automotive,
◦ biomedical, consumer,
◦ electrical and electronics products.

12. LIQUID BASED, SOLID BASED,
POWDER BASED

13.  Liquid-based RP systems have the initial form of
its material in liquid state.
 Through a process commonly known as curing,
the liquid is converted into the solid state.
 The following RP systems fall into this category:
1) 3D Systems’ Stereolithography Apparatus (SLA)
2) Cubital’s Solid Ground Curing (SGC)
3) Sony’s Solid Creation System (SCS)
4) CMET’s Solid Object Ultraviolet-Laser Printer (SOUP)

14. 5) Autostrade’s E-Darts
6) Teijin Seiki’s Soliform System
7) Meiko’s Rapid Prototyping System for the Jewelry
Industry
8) Denken’s SLP
9) Mitsui’s COLAMM
10)Fockele & Schwarze’s LMS
11)Light Sculpting
12)Aaroflex
13)Rapid Freeze
14)Two Laser Beams
15)Micro-fabrication

15.  As is illustrated in the RP Wheel in Figure 2.1, three
methods are possible under the “Photo-curing” method.
◦ The single laser beam method is most widely use and
includes all the above RP systems with the exception of (2), (11),
(13) and (14).
◦ Cubital (2) and Light Sculpting (11) use the masked lamp
method, while the two laser beam method is still not
commercialized.
◦ Rapid Freeze (13) involves the freezing of water droplets and
deposits in a manner much like FDM to create the prototype.
 .

16.  Except for powder, solid-based RP systems are
meant to encompass all forms of material in the
solid state.
 In this context, the solid form can include the shape
in the form of
◦ a wire, a roll, laminates and pallets.
 The following RP systems fall into this definition:
1)Cubic Technologies’ Laminated Object Manufacturing
(LOM)
2)Stratasys’ Fused Deposition Modeling (FDM)

17. 3) Kira Corporation’s Paper Lamination Technology (PLT)
4) 3D Systems’ Multi-Jet Modeling System (MJM)
5) Solidscape’s ModelMaker and PatternMaster
6) Beijing Yinhua’s Slicing Solid Manufacturing (SSM),
Melted Extrusion Modeling (MEM) and Multi-Functional
RPM Systems (M-RPM)
7) CAM-LEM’s CL 100
8) Ennex Corporation’s Offset Fabbers

18.  Referring to the RP Wheel in Figure 2.1, two
methods are possible for solid-based RP systems.
 RP systems (1), (3), (4) and (9) belong to the
Cutting and Glueing/Joining method,
 while the Melting and Solidifying/Fusing
method used RP systems (2), (5), (6), (7) and (8).

19.  In a strict sense, powder is by-and-large in the
solid state.
 However, it is intentionally created as a category
outside the solid-based RP systems to mean
powder in grain-like form.
 The following RP systems fall into this definition:
1) 3D Systems’s Selective Laser Sintering (SLS)
2) EOS’s Corporation EOSINT Systems
3) Z Corporation’s Three-Dimensional Printing (3DP)
4) Optomec’s Laser Engineered Net Shaping (LENS)

20. 5) Soligen’s Direct Shell Production Casting (MJS)
6) Fraunhofer’s Multiphase Jet Solidifcation (MJS)
7) Acram’s Electron Beam Melting (EBM)
8) Aeromet Corporation’s Lasform Technology
9) Precision Optical Manufacturing’s Direct Metal
Deposition (DMDTM
)
10)Generis’ RP System (GS)
11)Therics Inc.’s Theriform Technology
12)Extrude Hone’s PrometalTM
3D Printing Process

21.  All the above RP systems employ the
Joining/Binding method.
 The method of joining/binding differs for the above
systems in that some employ a laser while others
use a binder/glue to achieve the joining effect.

22. PROCESS, MATERIAL,
ADVANTAGES, LIMITATIONS

23.  History:
◦ Worldwide first RP-technology at all
◦ Patented 1984
◦ Commercialized 1988 by 3D-Systems Inc.
 The generative approach:
◦ Production of parts by addition of material instead of removal
(like for example by cutting,etc)
◦ Layer-by-layer build up >>bottom-to-top<<
◦ Easy manufacture of undercuts, complex structures, internal
holes

24.  Realization by Stereolithography
◦ Local solidification of a light-sensitive liquid resin
(photopolymer) using an UV laser
◦ Scanning of the cross-section areas to be hardened
with the laser focus.

25.  Layer – by – layer curing of a liquid
photopolymer by a laser
 Control of laser by a scan-mirror system

26.  Process steps
◦ Lowering of table by the thickness of one layer
◦ Application/leveling of liquid resin
◦ Scanning with laser
◦ Again lowering of table
 Supports
◦ Needed for manufacture of undercuts
◦ Build up with part similar to a honey-bee-structure

27.  Process chain of SLA

28.  Process chain of SLA (Cont..)

29.  Only photopolymer of different qualities
available
◦ temp.-proof,
◦ flexible,
◦ transparent etc)

31.  High part complexity
 High accuracy
 Support structure required

32.  Part size: 250x250x250 mm3
to 1000x800x500
mm3
 Accuracy: 0.05 mm
 Facility costs: 50 000 – 605 000 US$

33. PROCESS, MATERIAL,
ADVANTAGES, LIMITATIONS

35.  Melting of a wire-shaped plastic material
and deposition with a xy-plotter
mechanism
 Characteristics
◦ Limited part complexity
◦ Two different material for part and support

36.  Thermoplastics
◦ ABS,
◦ Nylon,
◦ Wax etc)

38.  Fabrication of functional parts
 Minimal wastage
 Ease of support removal
 Ease of material change

39.  Restricted accuracy – filament diameter 1.27mm
 Slow process
 Unpredictable shrinkage
 Part size: 600x500x600 mm3
 Accuracy: +/- 0.1 mm
 Facility costs: 66 500 – 290 000 US$

40. PROCESS, MATERIAL,
ADVANTAGES, LIMITATIONS

41.  TYPE 1
◦ Produced by 3 D Systems, USA
◦ Developed & patented by Univ of Texas,
Austin
◦ Material: only technology directly process
thermoplastic, metallic, ceramic &
thermoplastic composites
◦ Model: sinter station 2000, 2500 & 2500plus
,
Vanguard

43.  TYPE 2
◦ Produced by EOS, Germany
◦ First European for plastics, & manufacturer
◦ Capable to produce 700 x 380 x 580 (mm)
◦ First worldwide system for direct laser sintering
◦ Model:
 EOSINT P – thermoplastic ( eg nylon )
 EOSINT M – metal
 EOSINT P 700 – plastic

45.  Local melting/sintering of a powder by a laser
 Direct: the powder particles melt together
 Indirect: the powder particles are coated with a
thermoplastic binder which melts up
 Characteristics
◦ High part complexity
◦ Many materials available
◦ Burning out of the binder and infiltration might be
required
◦ Relatively high porosity and surface roughness
◦ Usually no supports needed

47.  Wax
 Thermoplastics
 Metal
 Casting sand
 Ceramics

49.  TYPE 1 (3D System)
◦ Good part stability –precise controlled environment
◦ Wide range of processing materials – nylon,
polycarbonates, metals etc
◦ No part supports required – material as support
◦ Little post-processing required - blasting & sanding
◦ No post-curing required – model solid enough

50.  TYPE 2 (EOS)
◦ Good part stability –precise controlled environment
◦ Wide range of processing materials – polyamide,
polystyrene, metals etc
◦ No part supports required or only simplified support –
reduce building time
◦ Little post-processing required – good model finishing
◦ High accuracy – low shrinkage & in separation building
◦ No post-curing required – model solid enough
◦ Built large part – large build volume (700x380x580)

51.  Part size: 250x250x150 to 720x500x450 mm3
 Accuracy: +/- 0.1 mm
 Facility costs: 275 000 – 850 000 US$

52.  TYPE 1 (3D System)
◦ Large physical size of the unit – need big space.
◦ High power consumption – high wattage of laser for
sintering.
◦ Poor surface finish – use large particle powder
 TYPE 2 (EOS)
◦ Dedicated systems – for plastic, metal & sand only.
◦ High power consumption – high laser power for metal
sintering.
◦ large physical size of unit – use large space

53. PROCESS, MATERIAL,
ADVANTAGES, LIMITATIONS

54.  Produced by Z Corporation, USA
 Core Technology invented & patented by MIT
 Materials: starch & plaster formulations
 Model:
◦ Z 400 – entry level & education
◦ Z 406/ 510 – Color Printer builds
◦ Z 810 - large build volume

56.  Local bonding of starch powder by a binder
using an ink jet (patent of MIT)
 Characteristics
◦ Very high building speeds
◦ Easy handling
◦ Binder available in different colors
◦ Infiltration necessary
◦ Ideal for fast visualization

58.  Process steps
◦ Spread a layer of powder
◦ Print the cross section of the part
◦ Spread another layer of powder
◦ Parts are printed with no supports to remove
◦ Refer z corp.doc

62.  Starch powder (Z Corp.)
 Other manufactures offer systems for
ceramics or metals

63.  High speed – layer printed in seconds
 Versatile - used for automotive, aerospace,
footwear, packaging, etc
 simple to operate - straightforward
 No wastage of material – can recycle
 colour – enable complex colour scheme

64.  Part size: 200x250x200 mm
 Resolution 600 dpi in x-y-direction
 Facility costs: 49 000 – 67 500 US$
 Limited functional parts – models are weak
 limited materials – starch & plaster-based only
 poor surface finish – need post-processing