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STEREOLITHOGRAPHY

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Presented By:
Abhijit Mishra

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PROTOTYPING
Subtractive (Conventional Process)
Milling
Grinding
Turning
Compressive
Additive
Photopolymer
Thermoplastic
Adhesives






Why Rapid Prototyping
Reduce product development time and cost
Get products to market sooner
Enhance communications between marketing, engineering, manufacturing, and purchasing
Present physical model at critical design reviews
Generate precise production tooling




Rapid Prototype Process
Creation of a 3-D model of a object in a CAD program

BASIC PROCESS
Create CAD model of the design
Conversion to STL format
Slice the STL file
Layer by layer construction
Cleaning and finishing
Slices

Conversion of a solid model of an object into layers (only one layer is shown)
Software chops your CAD model up into thin layers -- typically five to 10 layers/millimeter
SLA Interface
Stereolithograpy was first commercial Solid Freeform Manufacturing process, released in 80â„¢s by 3-D Systems

3-D Systems developed interface between CAD systems and their machine

STL files (*.stl) allow CAD systems to interface with 3-D system machines

Many CAD programs now can export the *.stl file for easy conversion from CAD to part
PARTS OF A SLA MACHINE
Tank filled with several gallons of liquid photopolymer.
The photopolymer is a clear, liquid plastic.
A perforated platform immersed in the tank.
The platform can move up and down in the tank as the printing process proceeds.
An ultraviolet laser
A computer that drives the laser and the platform
A typical StereoLithography apparatus
INSIDE OF SLA MACHINE
SLA PLATFORM
STEREOLIHOGRAPHY PROCESS
Polymer solidifies when struck by the laserâ„¢s intense UV light
Elevator lowers hardened cross section below liquid surface
Laser prints the next cross section directly on top of previous
After entire 3-d part is formed it is post-cured (UV light)


Stereolithography:
(1) at the start of the process, in which the initial layer is added to the platform; and (2) after several layers have been added so that the part geometry gradually takes form
StereoLithography Overview
Applications
Aesthetic & conceptual models
Parts requiring detail & accuracy
Master patterns for castings
Crisp, highly-detailed pieces
Speed of delivery (usually 2-3 days)
Tolerances within .005"/inch
Save Money
Save Time
Improve Design
Rapid Manufacturing






Conclusions
Stereolithography is fast and effective.
Stereolithography can be applied to almost every industry, including oil refining, petrochemical, power and marine.
Stereolithography saves time, money, allows speed delivery, and improve designs