3. What is Rapid Tooling
Rapid tooling is a term used to describe a process which
either uses a rapid prototyping model as a pattern to create a
mould quickly or uses the rapid prototyping process directly
to fabricate a tool for a limited volume of prototypes.
The most common rapid tooling methods are
Keltool
Sprayed metal tooling
ACES
Investment casting
Selective laser sintering
Stereolithography
4. Background
The term Rapid Tooling was introduced in the mid 1990s
Used to describe any method that would replicate an
injection mould to manufacture a physical plastic or metal
part
In 1989 the program tomorrows world on the BBC showed
the first stereolithography machines to be installed at BAe
systems
1992 Tim Plunket, managing director of Formation Limited,
attempted to make a company from the new technology of
stereolithography
5. Examples of Rapid Tooling Products
(a) (b)
(a) Example of a porous metal mould made by rapid tooling
http://www.physorg.com/news176456761.html (b) Shows an example of a plaster
mould made by rapid tooling http://www.ultracast.com/mold-production.html
6. Examples of Rapid Tooling Products
(a) (b)
(a) An example of a case mould developed through rapid tooling
http://www.alibaba.com/product-gs/311652056/CD_container_mould_dvd_case_mould.
(b) Shows an example of a sand casting mould made by rapid tooling
http://www.objet.com/Misc/_Pages/Application_Notes_Left_Pane/Sand_Casting_Applica
7. Rapid Tooling Processes
Rapid tooling processes use CAD/CAM techniques to make
tools and moulds for product assessment, short production
runs and full production
Development cycles are shortened considerable and more
economic
8. RT Process Classification
Rapid tooling is classified in two different categories
Direct routes – uses the CAD file to produce the tool in the
final material
Indirect routes – uses a rapid prototyping model as a master
pattern or case to make the moulds by established, more
traditional, routes
9. Indirect Routes
Rapid prototyping moulds can be used as the master models for
several applications such as;
Silicone tooling to make wax models for investment casting
or cast plastic parts
Porous plastic moulds for pressure casting ceramics
Case moulds for bench casting
Patterns for sand casting metals
Wax rapid prototyping models for lost wax investment
casting
10. Rapid Tooling for Investment Casting
1. Pattern Creation 2. Tree Assembly
4. Fill with investment
3. Insert into flask
5. Wax melt-out6. Fill mould with
metal
7. Water-jet8. Finish
Simplest method of applying rapid-prototyping operations to
other manufacturing processes.
11. Rapid Tooling for Investment Casting
Rapid-Prototyping Operation
Stereolithography
• Used to create the pattern.
• Photopolymers are cured using UV light to build layers in a component.
• For investment casting the polymer must be able to melt and burn from the ceramic
mould.
12. Invisalign Orthodontic Aligners
These aligners are manufactured using a combination of rapid tooling and thermoforming.
They are an alternative to conventional orthodontic braces.
Rapid Tooling In Action
Polymer impression of
patient’s teeth
Aligner is produced by
thermoforming a
transparent plastic sheet
against the model
Model is produced on
stereolithography machine
of desired tooth profiles
Computer modelling used
produce CAD
representations of desired
tooth profiles
Patient uses aligner for two
weeks
Patient completes treatment
13. Injection Moulding is used in rapid tooling to produce moulds or mould inserts.
A CAD model is produced which can easily be edited.
A common use of this technique is producing moulds for the slip casting of
ceramics.
Rapid Tooling and Injection Moulding
Injection
Moulded
product
Mould
tool
created
using the
mould
insert
Slip
poured
into
mould
Slip
drained
from
mould to
attain
uniform
thickness
Removal
of excess
material
from
drainage
site
Finished
product
ready to
be fired
14. Rapid Tooling and RTV Moulding
Room-temperature Vulcanising (RTV) Moulding
The vulcanisation process uses a mixture of a polymer and a curing agent to change the
state of the polymer by forming crosslinking bonds between molecules.
Can be performed by preparing a pattern of a part by any rapid prototyping technology.
RTV rubber is poured over the pattern and allowed to set.
The mould is then used for injection moulding.
One of the main disadvantages of using this type of rapid tooling is that the mould has a
lesser mould life components within the rubber cause progressive damage.
Limited to as few as 25 parts.
15. Keltool Process
Keltool process starts by rapid prototyping a rubber mould,
which is then used to cast a steel powder and polymer binder
mixture which is left to cure into a green state.
Once cured, it is then fired, and copper is infiltrated into the
mould, resulting in a tool approx. 70%steel 30% copper.
This mould can then be polished or machined to increase
surface finish and good tolerances although finishing is
normally not required.
16. Keltool
Keltool Process created over 25 years ago by 3M
Process provides great accuracy and surface finish, made
primarily as a steel tool
Can be used to create accurate moulds
Mould life can range from 100,000 to 10,000,000 parts
Mould tools have limited size of volume, 150mm cubed
Companies sometimes join two keltool moulds together to
increase mould tool size.
Moulds are strong enough to withstand typical injection
mould temperatures in use
17. ACES (Acetal Clear Epoxy Solid)
ACES mould tool parts can be used as inserts in a standard
injection moulding machine, easing material handling and
integration to existing processes, as well as simplifying
logistical measures.
Mould created using Stereolithography method, providing
cavity on underside of mould. Two mould halves put
together which is then filled with epoxy, ceramics, low melt
metals or thermoplastics
Has a low tool life of 10 – 100 parts,
with the tool having a dynamic failure,
gradually degrading with each use.
18. Sprayed-metal Tooling
Rapid prototypying is used initially to create the baseplate
and part pattern with alignment tabs for the tool part. The
base pattern must be hand finished to ensure the mould has
the best quality to the specification required. This base is
then coated using a zinc-aluminium alloy. This alloy coating
and base are placed within a flask or tank which is then filled
with an aluminium powder-filled epoxy. Once cured, the
baseplate and pattern are removed and a second mould half is
created for injection moulding, completing the mould tool.
19. Sprayed-metal Tooling
• The mould tool is process dependant, so can be used
between 100-100,000 uses, as low pressure processes yield a
greater tool lifespan.
20. Direct Routes
The CAD file is used directly to produce the part without need
for further operations
Can be used for;
Selective Laser Sintering
Produces porous metal moulds by CAD/CAM
Plaster moulds made by CNC machining
3D printing
Uses a wide variety of material – steel, copper polyamide
etc.
21. Selective Laser Sintering
This method was introduced in 1999. It produces plastic parts,
of increasing size for a growing number of applications.
22. Selective Laser Sintering
Used in every stage of the product development cycle
One shot models
Functional test parts
Small production series
Series of 50 to 100 pieces or more
Engine block built on the EOSINT
P700 machine with a build volume of
700x380x580 mm
23. Fused Deposition Modelling
This process fulfils the growing demand for functional models.
Constructs three-dimensional objects from digital CAD data
Layers - +/- 0.127 - 0.254 mm thickness
FDM Center at Materialise
HQ in Leuven
24. Laminated Object Manufacturing
The first commercial LOM system was shipped in 1991
Produced in layers of thickness of typically 0.002-0.020 in
Solid sheets of material
Thermoplastic material used
Applications;
Form/fit testing
Less detailed parts
Rapid tooling patterns
25. Rapid Tooling Equipment
(a)
(a) A picture showing a stereolithography machine in operation
http://www.rtejournal.de/ausgabe4/index_html/1163/ (b) A selective Laser Sintering
machine http://www.directindustry.com
(b)
26. Rapid Tooling Equipment
(a)
(a) Vacuum casting Prototyping machine http://www.directindustry.com (b) The
latest development in Rapid tooling
http://www.ferret.com.au/c/Industrial-Laser-Services/New-rapid-tooling-technology-Lase
(b)
27. A New Rapid Tooling Process
1. A three-dimensional computer model of the mould is designed
on the computer
2. A plastic pattern with complementary shape to the mould is
fabricated using a RP process, such as Stereolithography
3. A thin metal layer is deposited onto the cavity side of the plastic
pattern using an electro-chemical process to form a metal shell. Then,
the metal shell is separated from the plastic pattern
4. Metal ribs are added to the back of the metal shell to increase the
strength of the metal shell
5. The backside of the mould is sealed to prevent leakage of the
metal powder. The tool is finished and ready for moulding operations
Shorter lead times
Low cost
Environmentally friendly as the metal powder used in the backing is
fully recyclable
28. A New Rapid Tooling Process
http://www.intechopen.com/articles/show/title/a_new_rapid_tooling_process
29. Advantages
-Reduced manufacturing time
-much less expensive
-Effective communication
-decreases development time
-removal of redundant features
-early viewing of the product
-early market testing
-early testing (assembly, functional)
30. Disadvantages
shorter tool life
-less accurate tolerances
-not suitable for large sized applications
-fail in product replication
-cost is debatable
-lacks an obvious stopping point
-Usually does not produce reusable batch code
31. Future Developments
tooling will become faster
reduced cost
reduced development time
more accurate (product testing will be more accurate to the
testing of a final completed product)
faster market testing
products can be optimised and released quicker
35. According to a report from manufacturing
consultancy Wohlers Associates, demand for
products and services from the rapid
manufacturing industry has been relatively
strong for most of the technology’s 22-year
history. Also, a report from Frost & Sullivan
found that the rapid prototyping and rapid
tooling market earned revenues of $300
million in 2006, but total worldwide revenue
is forecast to reach $859.4 million in 2013.
36. Summary
A process which uses rapid prototyping in the fabrication of
tools
Introduced in the mid 1990s
Commonly used to create moulds from various materials
Indirect routes
Rapid Tooling for Investment Casting
Stereolithography
Rapid Tooling for Injection Moulding
RTV Moulding
Keltool
ACES
Sprayed Metal Tooling
37. Summary
Direct routes
Fused Deposition Modelling
Laminated Object Manufacturing
Selective Laser Sintering
Produced by many forms of rapid prototyping technology
Becoming more popular with industry, interest is
continuously growing
Speeding-up the manufacturing process
