The document provides an overview of rapid prototyping, defining prototypes as early models used to test concepts. It describes various rapid prototyping processes categorized by material removal, material addition, and powder-based systems, detailing specific methods such as stereolithography, solid ground curing, laminated object manufacturing, fused deposition modeling, selective laser sintering, and three-dimensional printing. The document emphasizes the efficiency and technology of each method and its applications in creating functional parts.

1. INTRODUCTION TO
RAPID
PROTOTYPING
Presented by,
ROLWYN MARIAN CARDOZA
1RV18MMD15
M.Tech MACHINE DESIGN
RV COLLEGE OF ENGINEERING.

2. What is a PROTOTYPE ?
A Prototype is an early sample, model or release of a
product built to test a concept or process or to act as a
thing to be replicated or learned from.
Prototypes are usually incomplete examples of what a
final product may look like.

3. RAPID PROTOTYPING
Rapid Prototyping is the "process of quickly
building and evaluating a series of prototypes" early
and often throughout the design process.

4. CATEGORIES:
Material removal RP
 This involves machining , milling
and drilling using CNC machines .
 Starting material is often a solid
block of wax which is very easy to
machine.
 Removed material and even
prototype can be reused when
no longer needed.
 Wood , plastics , metals can also
be used as starting materials.
Material addition RP
It involves adding layers of
material, one at a time to build
solid part from bottom to top.
Starting materials :
1) Liquid monomers
2) Solid sheets
3) Powders

5. COMMON PROCEDURE

6. LIQUID-BASED RAPID
PROTOTYPING SYSTEMS
 Starting material is liquid .
 About a dozen RP technologies are in this
category
 Includes the following processes:
1. Stereolithography
2. Solid ground curing.

7. STEREOLITHOGRAPHY (STL)
RP process for fabricating a solid plastic part out of a
photosensitive liquid polymer using a directed laser beam
to solidify the polymer.

8.  Each layer is 0.076 to 0.50mm thick
 Scan speeds of STL lasers typically range between 500 and
2500 mm/s.
 The time required to build the part by this layering process
ranges from 1hour for small parts of simple geometry up to
several dozen hours for complex parts.
 After all of the layers have been formed, the photopolymer is
about 95% cured. The piece is therefore ‘‘baked’’ in a
fluorescent oven to completely solidify the polymer.

9. SOLID GROUND CURING
1 2
3 4 5

10. 6 7
8 9 10

11.  The sequence for each layer takes about 90 seconds.
 The hardening process takes 2 to 3 seconds for each
layer.
 Although we have described SGC as a sequential
process, certain steps (masking) are accomplished in
parallel.
 Throughput time to produce a part by SGC is claimed to
be about eight times faster than competing RP systems.

12. SOLID-BASED RAPID PROTOTYPING
SYSTEMS
 Starting material is a solid.
 Solid-based RP systems include the following
processes:
1. Laminated object manufacturing
2. Fused deposition modeling.

13. LAMINATED OBJECT
MANUFACTURING (LOM)
1. Platform
2. Feed roller
3. Heated lamination
roller
4. Laser cutter

14.  Sheet thickness is 0.05 to 0.50 mm.
 The laser is typically a 25 or 50 W CO2 laser.
 A sealing application is recommended, using a urethane,
epoxy, or other polymer spray to prevent moisture
absorption and damage.
 LOM part sizes can be relatively large among RP
processes, with work volumes up to 800 mm* 500 mm*
550 mm.

15. FUSED DEPOSITION MODELING

16.  Filament diameter= 1.25 mm.
 The extrudate is solidified and cold welded to the cooler
part surface in about 0.1 second.
 The layer thickness can be set anywhere from 0.05 to
0.75mm.
 About 400mm of filament material can be deposited per
second by the extrusion workhead.

17. POWDER-BASED RP SYSTEMS
 Starting material is powder.
 Powder-based RP systems include the following:
1. Selective laser sintering
2. Three dimensional printing
 A wide range of thermoplastics, composites, metals and
ceramics can be used in this process, thus providing an
extensive range of functional parts to be built

18. SELECTIVE LASER SINTERING
(SLS)

19.  Layer thickness is 0.075 to 0.50 mm
 Materials in SLS include polyvinylchloride,
polycarbonate, polyester, polyurethane, ABS, nylon, and
investment casting wax. These materials are less
expensive than the photosensitive resins used in
stereolithography.

20. Three-Dimensional Printing
(3DP)

21.  Starting materials in 3DP are powders of ceramic, metal,
or cermet, and binders are polymeric or colloidal silica
or silicon carbide
 Typical layer thickness ranges from 0.10 to 0.18 mm.
 The ink-jet printing head moves across the layer at a
speed of about 1.5 m/s .
 The sweep time, together with the spreading of the
powders, permits a cycle time per layer of about 2
seconds