CASE STUDY: Taking the bite out of sandcasting CLIENT: Jason Christopher PROJECT: Crocodile Sculpture

FDM for Sand Casting An Objective3D Case Study

The team at Objective3D produced these parts flawlessly

using their Fortus Production systems. The FDM printing

process saved me hours of meticulous modelling work and

the parts themselves proved durable enough to withstand

the rigours of the foundry, as well as providing a great finish

for the mould surface. Jason Christopher www.jasonchristopherartist.com

The Aim: To produce a FDM pattern to be used for sandcasting a

complex metal sculpture (model) which will be bronze electroplated as

the piece de resistance in an art exhibition.

The 3D Printing requirements: As the Fused Deposition Modelling

(FDM) model was to be used as a mould for sand-casting, the parts had

to be strong enough to withstand the pressure of the moulding process,

able to be sanded to a high surface finish and cost effective to reduce

the overall expense of the project.

Jason Christopher designed the sculpture for manufacture - this ensured

the design could be split in half and cast effectively. With this in mind,

the same process was applied to the 3D Printed model. The team at

Objective3D Parts sectioned the build file to allow sections to be built

simultaneously across six in-house Fortus FDM 400 production systems.

This substantially reduce production time and costs, reducing the

estimated build time from 400 hours to only 180 hours. This also

drastically reduced material costs as no support material was required

due to the clever work of Objective3Ds engineers. The pattern was also

built with a T20 tip in sparse filled and ABS-M30 which lead to additional

time and cost savings.

After the 3D Printing: The 3D Printed model was meticulously

prepared for shipping and sent to the Client who assembled the parts,

filled and sanded the joins and applied several coats of primer and paint

filler to the entire model for a smooth surface finish. From here, the

pattern is complete and ready for casting.

At the foundry, the pattern is used to create a negative impression in

compacted sand. This is then carefully prepared for the pour by cutting

in runners and rises to allow for draw (metal shrinkage). The mould is

then closed ready for the metal pour.

The metal is left to cool in the mould before the sand is excavated

leaving the raw cast behind. The runners and rises are removed

manually, before the two casts are machined to allow for tapping screws

which will hold the two sides together. Once assembled, the cast is

cleaned of any leftover sand, grease and oil before being electroplated

in bronze, giving its final dramatic appearance.

OBJECTIVE3D, 33-35 YAZAKI WAY, CARRUM DOWNS, VIC AUSTRALIA 3201 www.objective3d.com.au

3D Printed Benefits:

The FDM pattern is reusable

ABS-M30 is stable over time

Production time was halved

Artists time can be spent

creating additional works and

not modelling just one