STUDY NO.1

RAPID PROTOTYPING

INTRODUCTION TO RPT

Rapid prototyping (RP) is a technology wherein the physical modeling of a design is done

using a specialized machining technology. The systems used in rapid prototyping quickly

produce models and prototype parts from three-dimensional (3D) computer aided design

(CAD) model data, magnetic resonance imaging (MRI) scan data and such data created

from 3D digitizing systems. Using an additive approach for building shapes, the systems

in RP join different materials like liquids or powder to form some physical objects. Layer

by layer, the RP machines fabricate these powdered ceramic, wood, plastic and metal

powders using very small and thin horizontal cross sections of the generated computer

model. Rapid prototyping is an emerging technology, the definition of which is derived

from the key concept - making it rapid. Rapid prototyping is creating a profound impact

on the way companies produce models, prototype parts, and tooling. A few companies are

now using it to produce final manufactured parts. It is believed that rapid prototyping shall

occupy a major share in manufacturing techniques in the years to come.

Rapid manufacturing may be considered as an extension of Rapid-Prototyping technology.

It involves automated production of pans by inanictions directly fed by the CAD data

which is modeled earlier. Currently, only a few final products are prepared by these

machines. This technology is not suitable for mass production but for small batches and

one-off production articles, it is cheaper since no tooling is involved. Some of the final

components that are produced are: customized dinner-wares, helmets for individual heads

(customized), jewellery patterns, spark erosion electrodes and reverse engineering pans.

STEPS IN RPT

• Creation of the CAD model of the (part) design,

• Conversion of the CAD model into Standard Tessellation Language (STL) format,

• Slicing of the STL file into thin sections,

• Building part layer by layer,

• Post processing/finishing/joining.

MAJOR RP TECHNOLOGIES:

1. Photo Masking or Solid Ground Curing technique.

2. LOM (Laminated Object Manufacturing)

3. SLA (Stereolithography)

4. FDM (Fused Deposition Modeling)

5. SLS (Selective Laser Sintering)

6. Thermo Jet Process

7. 3D Printing

8. Ballistic Particle Manufacturing (BPM)

APPLICATIONS OF RPT:

• It is mainly used in modeling, Product Design and Development,

• Reverse Engineering applications,

• Short Production Runs and Rapid Tooling,

In medical applications, RPT is used to make exact models resembling the actual pans of

a person, through computer scanned data, which can be used to perform trial surgeries,

• RP techniques are used to make custom-fit masks that reduce scarring on burn victims,

• Selective laser sintering (SLS) has been used to produce superior socket knees,

• Very tiny, miniature parts can be made by electrochemical fabrication,

• In jewelry designs, crafts and arts.

FUTURE DEVELOPMENTS:

• As the Rapid Prototyping Technology gets further advanced, it can lead to substantial

reduction in build-up time for manufacturing.

• Further improvement in laser optics and motor control can improve the accuracy.

• The development of new materials and polymers so that they are less prone to curing

and temperature induced warpages.

• Much anticipated development is the introduction of non-polymeric materials including

metals, ceramics, composites and powder metallurgy.

• Developments in ceramic composites can further increase the range of rapid

prototyping.

• Currently, the size is also a restriction; capability for larger parts shall be expected in

the near future.

• Currently, the demand is low and with the hunter technology advancement, awareness

and training, this can be increased.

• Advancement in computing systems and viability to support net designs from a distant

country to be fed directly on the RP machines for manufacturing is a new possibility.

LIMITATIONS AND CHALLENGES AHEAD:

• Unfamiliarity with the application of RPT exists. Therefore, its complete adaptability a

And how exactly this new and advanced technology will be of help and is not known.

• In view of high equipment cost, very few organizations can invest in these new

machines.

• Currently, RPT is more limited to modeling, specimen making and designing.

• The RPT is at present limited to making of paper and plastic type products only.

• Replacing steel by composites is still not easy and people fear its implications.

• RP companies usually limit the marketing efforts and industry awareness; hence most

engineering and manufacturing professionals are not fully aware of the RP potentials.

The SD300 Printer

• Creates 3D models

• Concept modeler Plus:

Creates parts for evaluation, demonstration and functional verification

• Desktop user friendly machine

• Office environment

• Intended for: engineers, industrial designers, 3D model users

SD300 Capabilities – Specifications

• Build material – Engineered plastic

• Material color – amber transparent

• Maximum model size – 160 W, 210 L, 135 H

• Accuracy – 0.2 mm (x,y); 0.3 mm (z)

• Input file formats – STL

• Minimum wall thickness –1 mm

Technology and operation concept

• Bottom to top layer by layer build-up

• Layer build-up cycle :

1. Preparing a new plastic sheet layer in the buffer

2. Glue application on the whole area

3. Ironing the new plastic sheet layer on the model block

4. Cutting the new plastic sheet layer according to the pattern

5. Trimming the new plastic sheet layer and roll back

6. Masking fluid application by the 3 AG pens

7.

SD300 3D Printer – Components and parts

1. Top door

2. Side covers

3. Material compartment doors

4. Heating system

5. Operating panel

6. Feeder tray

7. Ironing unit

8. Work table

9. XY Plotter head

10. Cutting knife

11. Trim knife & Anti Glue pen station

12. Rear Panel :

• On/Off Switch

• Fuse

• Power cable inlet

• USB Connection

• Ventilation openings

• Anti Glue Cartridge

Material Kit – Consumables

Plastic Material roll – loading and replacement

Glue container – loading and replacement

AG cassette – replacement

AG pens – replacement

Getting started (practice)

Initializing the printer

Consumable loading:

- Material roll

- Glue cartridge

- AG cassette and pens

Hands on practice

Control Panel and Menu options

1. Cancel model (NO / YES (finish layer))

2. Lift model (yes/no)

3. Un-feed media (yes/no)

4. Initialize (yes/no)

5. Build test model (yes/no)

6. Firmware version

Sdview application software – Model preparation

Importing STL files

Placing models on work table

Scale, duplicate, rotate, chop, join, etc.

Viewing the model geometry

Placing additional cuts

File management (SDM format)

Build model

SD300 3D Printer – The Workflo

1. Click “BUILD” and send the build file to the SD300 3D printer

2. Retrieve your model

3. Simply peel away the support material

SD300 3D Printer – Support Removal

Clean, dry parts, no chemicals or washes

No special tools or lab equipment required

Peeling cuts allow easy peeling of complicated geometries

Z-Fold allows fast, continuous removal of excess material

Geometry capabilities – What can you build ?

Full size parts – Up to build spec

Thin walls and small features – 1mm wall thickness required

Cavities and Holes

Under Cuts

Posts, snaps and pins – 1mm wall thickness required

TROUBLESHOOTING

Panel errors:

Motor protection

Xy home error

Z home error

Door open error

Height check error

Trimming error

Take/return tool error

Hook error

Iron home error

No media

Feeding error

Ironing error

Remove previous model

No magnet error

Replace cutting knife

Troubleshooting:

Printer power

Solid VC material feeding

Broken knives

AG pens

AG cassette

Glue application

Peeling

SD300 3D Printer – User maintenance

Clean printer after each build

Glue residues

AG residues

Plastic sheet particles

Test build in case the printer was not in use for a week

Clean bubbles – if necessary

SD300 3D Printer – Machine Safety

Electrical safety measures

Keep work area clear and free of clutter

Inspect the power cord periodically for cracks, kinks or any other signs of wear

Do not pull the Printer by the cords

Keep the area dry

Keep the area well lit

Do not touch any moving parts

Clean up any spills immediately. Good house keeping pays

Do not wear loose clothing or dangling jewelry while working with the printer

Keep all doors and panels closed during operation

Working with the tweezers