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5.3.2 Products
5.3.2.1 Models and Specifications
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TM
TM
Z Corporation’s latest products are the Z 400, Z 406 and Z 810
TM
TM
systems. The Z 400 System replaces the Z 402 System and has the
TM
same speed and performance as the Z 402 system but is configured for
the entry-level and educational users. It does not come bundled with
training or post-processing units. The Z406 3D Color Printer builds
parts three to four times faster than Z402C and utilizes four print heads
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Table 5.3: Specifications of Z Corporation’s 3D Printers
Model
Build speed
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Z 400 3DP
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Z 406 3DP
2 layers / min
Z 810 3DP
Color: 2 layers / min
Monochrome:
6 layers / min
Build volume
(mm × mm × mm)
203 × 254 × 203
203 × 254 × 203
500 × 600 × 400
Layer thickness
(mm)
0.076–0.254
0.076–0.254
0.076–0.254
Equipment
dimensions
(mm × mm × mm)
740 × 910 × 1070
740 × 910 ×1070
1020 × 790 ×1120
Equipment weight
(kg)
136
136
210
System software
Z Corp.’s proprietary system software runs on Microsoft
Windows 2000 and NT. VRML, ZCP, PLY and SFX file
formats can be used for color input. STL file format is accepted
for monochrome parts.
Materials
Starch and plaster formulations.
as compared to Z402C. Its new print heads were developed by Hewlett
Packard. This new machine is the first product of a cross-licensing
agreement between HP and Z Corporation in the field of 3D printing.
ZTM810 System’s large build volume and inexpensive build materials
make it the fastest and the least expensive way to create large
appearance prototypes. The system also offers a variety of finishing
options including epoxy infiltration, sanding, painting and plating. The
option of color gives the user added information and aesthetics through
the ability to incorporate color directly into the part as it is being
printed [13]. Table 5.3 shows the specifications of Z Corporation’s 3D
printers.
The Z400 3D printer is the entry-level concept modeling solution
that delivers great models quickly and inexpensively. Models can be
used for design verification, communication and as patterns for casting
applications. Z Corporation offers a variety of materials for use with the
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TM
Figure 5.11: Z 406 3D printer
Z400 3D printer. Beginning with two basic materials, a versatile and
inexpensive starch-based powder and a high-definition plaster-based
powder, infiltrants can also be added to satisfy a wide range of
modeling needs.
The Z406 System is a premium 3D Printer with the capability
of printing in full-color, communicating important information about
parts, including engineering data, labeling, highlighting and appearance
simulation. It can print in six million colors and uses a new pigment
system developed by Cabot Corporation for fuller and brighter colors.
The software interface included with the new machine, MAGICS
Z allows users to add color information to STL files. It also includes
a labeling option that lets users add text such as dates or revision
coding directly to STL files. Figure 5.11 shows a photograph of Z
TM
Corporation’s Z 406 3D printer.
The Z810 System is the fastest and the least expensive way to
create large appearance prototypes for design review, mock-ups
for form and fit testing, and patterns for casting applications. The
large build volume allows full-scale concept models to be made
for more effective communication with marketing, manufacturing,
customers and suppliers. The Z810 System’s color capability allows
accurate representation of designs including FEA and other engineering
data, further enhancing communication. Physical models can be created
in plaster or starch-based materials and can be infiltrated to produce
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parts with a variety of material properties, satisfying a wide spectrum of
modeling needs.
Z Corporation also has an accessory, the ZW4 Automated Waxer, for
use with the 3D printers. The ZW4 Waxer allows printed parts to be
infiltrated with paraffin wax to enhance strength, provide uniform part
finish and color, or to create patterns suitable for investment casting.
5.3.2.2
Advantages
(1) High speed. Fastest 3D printer to date. Each layer is printed in
seconds, reducing the prototyping time of a hand-held part to 1 to
2 hours.
(2) Versatile. Parts are currently used for the automotive, packaging,
education, footwear, medical, aerospace and telecommunications
industries. Parts are used in every step of the design process for
communication, design review and limited functional testing. Parts
can be infiltrated if necessary, offering the opportunity to produce
parts with a variety of material properties to serve a range of
modeling requirements.
(3) Simple to operate. The office compatible Zcorp system is
straightforward to operate and does not require a designated
technician to build a part. The system is based on the standard, off
the shelf components developed for the ink-jet printer industry,
resulting in a reliable and dependable 3D printer.
(4) No wastage of materials. Powder that is not printed during the
cycle can be reused.
(5) Color. Enables complex color schemes in RP-ed parts from a full
24-bit palette of colors.
5.3.2.3
Disadvantages
(1) Limited functional parts. Relative to the SLS, parts built are much
weaker, thereby limiting the functional testing capabilities.
(2) Limited materials. The materials available are only starch and
plaster-based materials, with the added option to infiltrate wax
using the ZW4 Waxer.
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(3) Poor surface finish. Parts built by 3D printing have a relatively
poorer surface finish and post-processing is frequently required.
5.3.3 Process [14]
(1) The machine spreads a layer of powder from the feed box to cover
the surface of the build piston. The printer then prints binder
solution onto the loose powder, forming the first cross-section. For
monochrome parts, Z406 color printer uses all four print heads to
print a single-colored binder. For multi-colored parts, each of the
four print heads deposits a different color binder, mixing the four
color binders to produce a spectrum of colors that can be applied to
different regions of a part.
(2) The powder is glued together at where the binder is printed. The
remaining powder remains loose and supports the layers that will
be printed above.
(3) When the cross-section is completed, the build piston is lowered, a
new layer of powder is spread over its surface, and the process
is repeated. The part grows layer by layer in the build piston until
the part is completed, completely surrounded and covered by loose
powder. Finally the build piston is raised and the loose powder is
vacuumed, revealing the complete part.
(4) Once a build is completed, the excess powder is vacuumed and the
parts are lifted from the bed. Once removed, parts can be finished
in a variety of ways to suit your needs. For a quick design review,
parts can be left raw or “green.” To quickly produce a more robust
model, parts can be dipped in wax. For a robust model that can be
sanded, finished and painted, the part can be infiltrated with a resin
or urethane.
5.3.4
5.3.4.1
Examples
Sports Shoe Industry
The 3D printer has been used by designers, marketers, manufacturers,
and managers in the footwear industry. Leading athletic shoe
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Figure 5.12: Sports shoe design model created by Z Corporation system
(Courtesy of Z Corporation)
companies, such as Adidas, have used this RP system to radically
reduce prototype development time and communicate in new ways [15].
Shoe industries these days are faced with constantly changing consumer
preferences and have to react quickly to stay ahead of the business.
With the 3D printer, lead times are drastically reduced, beating the
competition to the shelves with the latest design trends whilst avoiding
an excess inventory of unwanted designs.
5.3.4.2
Javelin Puts Computer Sculpting in the Artist’s Hands
Javelin uses the Z402 System to produce computer-sculpted models to
assist artists with complex modeling. Parts produced find applications
with computer gamers, animators, pre-Hollywood mock-ups designers,
and sculpturing artists. The low cost associated with 3DP parts allows
several iterations to be used to accelerate the sculpting process. In one
instance, CT scan data and Velocity2 software were used to recreate a
dinosaur skull. They found that eliminating the need for support
structure in a file that exceeds 4 000 000 polygons was a great asset.
The CAD file from Velocity2 was sent to the Z402 System and the
“dino-head” (shown in Figure 5.13) was built within 7 hours [16].
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Figure 5.13: “Dino-head” produced by Javelin using the Z Corporation System
(Courtesy of Z Corporation)
5.3.5
Research and Development
On-going work to improve the versatility of the system in terms of
materials, efficiency and software are being carried out to allow new
applications.
5.4
5.4.1
OPTOMEC’S LASER ENGINEERED NET
SHAPING (LENS)
Company
Optomec Inc. was incorporated in 1992. Since 1997, Optomec has
focused on commercializing a direct fabrication process, the Laser
TM
Engineered Net Shaping (LENS ) process originally developed by
Sandia National Laboratories. Optomec delivered its first commercial
system to Ohio State University. The address of Optomec Inc. is 3911
Singer Boulevard, N.E., Albuquerque, NM 87109, USA.
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5.4.2 Products
5.4.2.1 Model and Specifications
TM
TM
The latest Optomec’s products are the LENS 750 and LENS 850
systems. These two systems feature the Laser Engineered Net Shaping
(LENS) process, a technology that builds or repairs parts using metal
powders to form fully dense objects to give excellent material
properties. This technique can be used with a wide variety of metals
including titanium, tool steels, stainless steels, copper and aluminum.
TM
TM
The LENS 750 and LENS 850 systems contains the following
hardware components as in Table 5.4.
Table 5.5 shows a summary of the models and specifications of the
TM
LENS systems. Figure 5.14 shows a photograph of Optomec’s LENS
750 system.
5.4.2.2
Advantages
(1) Superior material properties. The LENS process is capable of
producing fully dense metal parts [17]. Metal parts produced can
also include embedded structures and superior material properties.
The microstructure produced is also relatively good.
(2) Complex parts. Functional metal parts with complex features
are the forte of the LENS system.
(3) Reduced post-processing requirements. Post-processing is
minimized, thus reducing cycle time.
Table 5.4: Hardware components of the LENS systems
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LENS 750
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LENS 850
Argon recirculation unit
Argon recirculation unit
Laser power supply
Laser power supply
Ante-chamber
Ante-chamber
Workstation
Workstation
Process chamber and dri-train
Glove box
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