Complex patterns for investment casting cannot be drawn out of a mould and they have to be destroyed. An alternative is to use the Rapid Prototyping machine but this is a slow process. Therefore, a process created using Layered manufacturing to solve this problem and a physical model was obtained for further analysis.

1. High productivity layered manufacturing of complex patterns for investment casting
Arvindsing Seewoosungkur I.D Number: 000 39 38 43-3 BEng (Hons) Mechanical Engineering 2008/2009
1.Complex patterns for investment casting cannot be drawn
out of a mould and they have to be destroyed. An
alternative is to use the Rapid Prototyping machine but this
is a slow process. Therefore, a process created using
Layered manufacturing to solve this problem and a
physical model was obtained for further analysis.
1.1 Aim
To develop a method for obtaining a high productivity,
maintain good surface quality, dimensions accuracy and
low cost solution.
1.2 Objectives
• Investigate, design, implement and test the technique
adopted.
• Comparison of productivity rate, dimensions
accuracy and surface quality of the new technique to
an existing one.
0
2
4
6
8
10
12
14
16
18
Numberofhours
FDM 16.5
LMM 2.1
0
1
2
3
4
5
6
7
8
Numberofpounds£
•The layered manufactured mould designed was highly productive with a
time of 2.1 hours compared to the FDM three dimensional printing
“Thermojet” with time of 16.5 hours to obtain a model ready for use after
post processing.
•The dimensional accuracy minor errors varying between 0.5
mm to 0.75 mm in certain regions.
•The quality from the layered manufactured mould was not as good as the
one from the FDM machine.
• The process is very cost effective ,LMM £0.2 and FDM £7.35.
Figure 12:The dimensional
accuracy for FDM model
Figure 13:The dimensional
accuracy for LMM model
LMM 0.2
FDM 7.35
Future works
• Improvement on quality and slicing process.
• Full automation of the system.
Time
lead-time is too
long for large
quantities < 1000
Cost very high
Quality
Service to
customers
Time(s)
0
+25
+30
+55
±75
165
Total time
~ 2.1 mins
2. Problem Analysis
3. Idea generation and Solution
Complex
Model
4. ImplementationIntroduction
5. Results and discussion
6.Conclusion
Acknowledgements
Special thanks to my project supervisor Dr.Dele Owodunni for his support.
Figure 2: The subtraction
Figure 3: The internal features
Figure 4: The slicing with planes
Figure 5: The layered manufactured mould
(L.M.M)
Figure 6:The layer
Separate bodies on the
same plane The joining process
Figure 8:The use support material
Figure 7:An overhanging part
Liquid wax does not
hold
Before
After
Figure 9:The working principles
Figure 10:The manufacturing time Figure 11:The material cost
Figure 14:The magnified view FDM
model 1:70
Figure 15:The magnified view for
FDM model 1:50
Figure 1:The model to be reproduced as the key element