rapid-prototyping

1. RAPID PROTOTYPING

2. INTRODUCTION OF RAPID PROTOTYPING
• Is a revolutionary and powerful technology
with wide range of application.
• The process of prototyping involve quick
building up of a prototype or working
model for the purpose of testing the
various design features,
ideas,concepts,funtionality,output and
performance.

3. HISTORY OF RAPID PROTOTYPING
• In 60’s ,the first rapid prototyping
technique became accessible in the later
eighties and used for production of
prototype and model parts.
• In 70’s ,Herbert Voelcker, engineering
professor developed the basic tools of
mathematics that clearly describe the
three dimensional aspects and resulted in
the earliest theories of algorithmic and
mathematical theories for solid modeling.

4. • In 80’s, Carl Deckard ,researcher from the
University of Texas. He pioneered the layer based
manufacturing , he thought of building up the
model layer by layer. He printed 3D models by
utilizing laser light for fusing metal powder in
solid prototypes,single layer at a time. Technique
called ‘Selective Laser Sintering’.
• Nowadays , the computer engineer has to simply
sketch the ideas on the computer screen with the
help of a design program that is computer aided.
Computer aided designing allows to make
modification as required and can create a physical
prototype that is a precise and proper 3D object.

5. THE ADVANTAGE OF RAPID PROTOTYPING
• CAD data files can be manufactured in hours.
• Tool for visualization and concept verification.
• Prototype used in subsequent manufacturing
operation to obtain final part.
• Tooling for manufacturing operation can be
produce.

6. SUBTRACTIVE PROCESS
• Is the prevent process in the history of model
making. Model makers once utilized materials
like clay and wood or other hard material, to
whittle, carve, or sculpt a model component.
• The excess material was basically chiseled, cut,
and sanded to expose the design within the
carving medium.
• This process was understandably time intensive
and resulted in a finished product that was a
one of a kind and could not be easily replicated
without remaking the part from scratch.

7. ADDITIVE PROCESS
• Is built by adding layers of material upon one
another.
• This process are inhenrently different from
subtractive processes or consolidation
processes. Example such as milling ,turning or
drilling, use carefully planned tool movement
to cut away material from a workpiece to form
the desired part.
• The part is constructed directly from a digital
3D model created through Computer Aided
Design (CAD) software.

8. VIRTUAL PROCESS
• To create each virtual cross section in then takes physical form
layer after until an identical prototype model is created.
THE FUSED DEPOSITION MODELLING (FDM)
• Process constructs three-dimensional objects directly
from 3D CAD data. A temperature controlled head
extrudes thermoplastic material layer by layer.
• This model is oriented and mathematically sliced into
horizontal layers varying from +/- 0.127 – 0.254mm
thickness.
• The system operates in X, Y and Z axes, drawing the
model one layer at a time.

10. STEREOLITHOGRAPHY
• is an additive manufacturing process using a vat
of liquid UV curable photopolymer ‘resin’ and UV
laser to build parts a layer at a time.
• The laser beam traces a part cross section pattern
on the surface of the liquid resin.
• After a pattern has been traced, the SLA’s elevator
platform descends by a single layer thickness,
typically 0.05mm to 0.15mm. Then, a resin filled
blade sweeps across the part cross
section,recoating it with fresh material.

12. SELECTIVE LASER SINTERING (SLS)
• Is a layer additive production process that creates three
dimensional object using CO2 laser to melt, or sinter and
fuse selective powder molecules based on information
supplied by a computer aided design (CAD) file.
• Commonly called thermoplastic material or in some
cases, thermoplastic binders for use in metals.
• Allows for these materials to be fused together in tiny
layers ranging between .003” and .006”.
• Parts and or assemblies that move and work that have a
good surface finish and feature detail.
• SLS gives the capability of flexible snaps and living
hingers as well as high stress and heat tolerance.

13. BALLISTIC
• The BPM personal modeler came with all hardware and
software enclosed in one compact unit.
• The BPM utilized ink jet or droplet based manufacturing
techniques, it builds the models by firing micro droplets
of molten wax material from a moving nozzle or jet onto
a stationary platform, the platform then lowers and the
process is repeated for each layer of the model.
• The parts can be scaled, rotated or translated to a
desired orientation. This is performed on a 5 axis
workstation.

14. LAMINATED
• That uses a carbon dioxide laser to create
successive cross section of a three
dimentional object from layers of paper
with a polythylene coating on the backside.
The first step is to creates a base om which
the paper can attach itself.

15. HIGHLIGHTS OF LAMINATED OBJECT MANUFACTURING
• Layers of glue-backed paper form the model.
• Low cost:Raw material is readily availabel.
• Large parts: Because there is no chemical reaction
involved,parts can be made quite large.
• Accuracy in z is less than that for sterrolithography and
selective laser sintering . No milling step
• Outside of model,cross –hatching removes material
• Model should be sealedin order to prohibit moisture.
• Before sealing ,models have a wood-like texture.
• Not as prevalent as stereolithograhy and selective laser
siterning.

16. METHODOLOGY FOR RP PROCESS
The basic methodology for all current rapid prototyping
techniques can be summarized as follows:
1. A CAD model is constructed, then converted STL format
. The resolution can be set to minimize stair stepping.
2. The RP machine processes the STL file by creating
sliced layers of the model.
3. The fisrt layer of the physical model is created .The
model is then lowered by the thickness of the next
layer, and the process is repeated until completion of
the model
4. The model and any supports are removed. The surface
of the model is then finished and cleaned.

17. RAPID TOOLING
• A process that is the result of combining Rapid
Prototyping techniques with conventional tooling
practices to produce a mold quickly or part of a
functional model from CAD data in less time and at
lower cost relative to traditional machining method
.Rapid Tooling can act as brige to production injection
molded parts.
• The main advantage are tooling time is much shorter
than for a conventional tool. Time to first articles can
be less than one fifth that of conventional tooling;
tooling cost is much less than for a conventional tool.
Cost can be below five percent of conventional tooling
cost.
• The main challrnges are tool life is less than for
conventional tools and tolerances are wider than for
conventional tools.

18. TYPES OF RAPID TOOLING PROCESS
-Low Volume (from tens to hundreds)
- Soft tooling
-Reaction injection molding
-Bridge Tooling –Direct Access Injection Molding
Intermediate (from hundreds to thousands)
- Metal filled epoxy tooling
- Powdered metal tooling
- space puzzle molding