Additive manufacturing

1. Rapid Prototyping
Compiled by
Er Bijendra Prajapati
Lecturer
Department of Mechanical & Aerospace Engineering
Pulchowk Campus

2. Contents
• Manufacturing
• Introduction to RP
• Applications, Classification, Demonstration
– Fused deposition Modeling
– Stereolithography
– Selective laser sintering
• Print quality troubleshooting
• Sites for CAD models
• 3D printers in Nepal & their applications

3. Manufacturing
1. Subtractive Manufacturing such as milling or turning,
2. Formative Manufacturing such as casting or forging,

4. Contd…
3. Additive Manufacturing (Rapid Prototyping)
Generative Manufacturing , layer-based
technology, 3D printing

5. Introduction
• Rapid prototyping is the name given to a host of related
technologies that are used to fabricate physical objects
directly from Computer-Aided Design (CAD) data sources.
• These methods are generally similar to each other in that they
add and bond materials in layerwise-fashion to form objects.

6. Process of Rapid prototyping

7. Contd…
Nowadays, there are over 30 processes, some of which are commercial, while
others are under development in research laboratories.
The parts are more and more frequently being used for functional testing or to
derive tools for pre-production testing than just prototype.

8. Why Rapid?
• Rapid prototyping isn’t necessarily very rapid and doesn’t
necessarily have to do with prototypes, either. Speed is
relative:
• The processes can take weeks to months off a design cycle,
but still may require many hours to fabricate a single
object.
• Therefore “rapid” is a relative term. Most prototypes
require from three to seventy-two hours to build,
depending on the size and complexity of the object.
• This may seem slow, but it is much faster than the weeks or
months required to make a prototype by traditional means
such as machining.
• These dramatic time savings allow manufacturers to bring
products to market faster and more cheaply .

9. Applications of Rapid Prototyping
Widely used in the
• Industrial 3D Printing
– Automotive
– Aerospace & Defense
– Healthcare
– Consumer Electronics
– Industrial
– Power & Energy
– Others
• Desktop 3D Printing
– Educational Purpose
– Fashion & Jewelry
– Objects
– Dental
– Food
– Others
• Design,
• Medical, and
• Consumer products
industries.
• Personal hobby
Although the possible
applications are virtually
limitless, nearly all fall into
one of the following
categories:
• Prototyping,
• Rapid tooling, or rapid
manufacturing.

15. Classification of RP

16. Raw materials and application of different technology
Fig. Prototype tooling; rubber boot sole mold;
laser sintering

17. Fused Deposition Modeling
It uses a continuous filament of a thermoplastic
material and builds a part by heating and
extruding this thermoplastic filament through a
moving, heated extrusion print head one layer
each time

18. FDM Basics

23. Materials for FDM

24. Contd….

27. Stereolithography (SLA)
• Stereolithography is not only the oldest but also still the most
detailed AM process.
• Invented & 1st commercialized by 3D Systems, Rock Hill, SC, USA
• The technique builds three-dimensional models from liquid
photosensitive polymers that solidify when exposed to ultraviolet
light.
• The laser beam is directed by a galvo-type scanning device that is
controlled according to the contour of each layer.

32. Selective Laser Sintering (SLS)

33. Working
• Objects printed with SLS are made with powder materials, most
commonly plastics, such as nylon, which are dispersed in a thin
layer on top of the build platform inside an SLS machine.
• It uses a high power laser to sinter small parts of powdered
material aiming at specific points across a powder bed
• The laser heats the powder either to just below its boiling point
(sintering) or above its melting, which fuses the particles in the
powder together into a solid form.
• Once the initial layer is formed, the platform of the SLS machine
drops — usually by less than 0.1mm — exposing a new layer of
powder for the laser to trace and fuse together. This process
continues again and again until the entire object has been printed.
• When the object is fully formed, it is left to cool in the machine
before being removed.

34. Specifications of SLS printer

38. Print quality Troubleshooting

39. Contd…

40. Sinterit lisa SLS
Formlabs SLA
FDM Printers

41. Sites for CAD files for 3D printing

43. Sites for CAD models
• MyMiniFactory
• CGTrader
• Cults
• Pinshape
• YouMagine
• 3DExport
• 3Dagogo
• GrabCAD
• Repables
• Treatstock
Fig Steel mold for blow molding. Direct metal
laser sintering

44. Prominent players in the global 3D printing market
• Stratasys, Ltd.
• Materialise
• EnvisionTec, Inc.
• 3D Systems, Inc.
• GE Additive
• Autodesk Inc.
• Made In Space
• Canon Inc.
• Voxeljet AG

45. Applications in Nepal

46. Rapid Prototyping in Nepal

47. Official Distributor of Tiertime UP 3D Printer: Zener Technologies

48. Thank You