SAMPE Journal - November/December 2016 - 60

Feature Article
Table 1. Direct costs of AM process.

Table 2. Direct costs of traditional process.

Other Benefits of AM Tooling
In addition to the direct cost savings that can be
achieved using AM to produce tooling, AM offers
additional significant advantages. Current lead times
for composite tooling often span weeks or months if
tooling is not produced in-house. AM offers the ability
to drastically decrease lead times, which translates
to shorter delivery times and accelerated product
development cycles. In fact, lead time reductions
of up to 90% have been reported as a result of AM
made tooling1. For companies that produce tooling inhouse, purchasing a large scale AM machine could still
drastically reduce tool manufacturing times. Current
tool making processes require many material inputs and
extensive labor. If a tool was to be made from Invar or
tooling boards, it may take weeks for the correct sized
blocks to arrive. An AM machine can readily print any
shape with little to no set up time and supervision.
The high cost of composite tooling restricts
composites to expensive or high volume applications.
The cost savings and reduced lead times achievable with
large scale AM could drastically alter the economics of
composites manufacturing. New applications previously
not financially feasible could suddenly emerge as
contenders for composites. Economic order quantities
could greatly decrease if tools cost 1/10th the price,
making low volume applications attractive, even down
to individual custom parts. The high-mix low-volume
composites environments would thrive if this paradigm
shift in tool making could take place.

Temperature gradients that develop during printing
give rise to sometimes detrimental residual stresses
when printing large parts4. An ideal solution would
involve designing smart print paths in a way to lessen
these effects. Models are under development and must
advance in order to make smart print path generation a
reality.

Current Limitations of AM Tooling
As with any emerging technology, problems still remain
to be solved prior to acceptance beyond early adopters.
The extrusion of fiber-reinforced polymers in this AM
process typically results in significant fiber orientation in
the direction of deposition. Thus, the final CTE of the
extrudate and the tool are highly anisotropic. This can
present issues when matching tooling CTE to that of
the part being manufactured. In the future, tools may
be printed in multiple sections, such as printing backup
structure first and then a tool surface of varying bead
orientations on top of it. The A-frame tool made from 30
weight percent carbon fiber-reinforced PPS experienced
slight expansion through thickness during the cure
process. Where tight tolerances are required, greater
fiber content materials and increased backup structure
should be used.
60

Conclusion
The cost savings that can be achieved by utilizing
AM in the production of composite tooling were
demonstrated and estimated to be 50% for a small tool.
The savings are expected to become greater as tool
size and complexity increases. The current materials
that large scale commercial machines can print are
likely suitable for indirect rapid tool making, or making
masters that will be used to make tools. The technology
is advancing quickly and the commercial machines will
soon be moving to third generation customized AM
extruders. These machines will likely be printing high
fiber content and high temperature polymers suitable
for autoclave tools in the near future. The objective of
this paper is to motivate both early adopters in industry
and researchers around the world to continue to uncover
new applications and contribute to this exciting field with
much promise and potential.
References
1. Cotteleer, M., Neier, M., & Crane, J. (2014). 3D
Opportunity in Tooling. Deloitte University Press.
Retrieved from http://dupress.com/articles/additivemanufacturing-3d-opportunity-in-tooling/
2. Celstran LFRT Automotive [PowerPoint Slides].
Retrieved from http://www.celanese.com/engineeredmaterials/products/Celstran-LFRT/media-literature.aspx
3. Macy, B. (2011). Rapid/Affordable Composite
Tooling Strategies Utilizing Fused Deposition Modeling.
SAMPE Journal, Volume 47, No. 4. Retrieved from http://
www.stratasys.com/~/media/Main/Secure/White%20
Papers/2011_SAMPE_Journal.ashx
4. Kunc, V. (2015). Advances and Challenges in Large
Scale Polymer Additive Manufacturing [PowerPoint
Slides]. Retrieved from http://speautomotive.com/
SPEA_CD/SPEA2015/3d.htm
5. Big Area Additive Manufacturing. Retrieved from
URL http://www.e-ci.com/baam/
SAMPE Journal, Volume 52, No. 6, November/December 2016

ttp://dupress.com/articles/additive-manufacturing-3d-opportunity-in-tooling/ ttp://dupress.com/articles/additive-manufacturing-3d-opportunity-in-tooling/ http://www.celanese.com/engineered-materials/products/Celstran-LFRT/media-literature.aspx http://www.celanese.com/engineered-materials/products/Celstran-LFRT/media-literature.aspx http://www.stratasys.com/~/media/Main/Secure/White%20 Papers/2011_SAMPE_Journal.ashx http://www.stratasys.com/~/media/Main/Secure/White%20 Papers/2011_SAMPE_Journal.ashx http://speautomotive.com/SPEA_CD/SPEA2015/3d.htm http://speautomotive.com/SPEA_CD/SPEA2015/3d.htm http://www.e-ci.com/baam/

Table of Contents for the Digital Edition of SAMPE Journal - November/December 2016