Tooling

Graphite Additive Manufacturing Offers 3D Printed Mandrels

Tuesday, 25th September 2018

0 comments
Reading time: about 2 minutes

Compcut 200 Exceeds Expectations at the NCC

9th August 2019

Benefits of 3-D Woven Composite Fabrics

18th July 2019

Haydale at Goodwood Festival of Speed

17th July 2019

Graphite Additive Manufacturing’s stereolithography (SLA) process produces 3D printed mandrels suitable for manufacturing complex composite parts.

It has traditionally been difficult to provide high quality interior surfaces of traditional complex components made using aerospace and motorsport-grade autoclave-cured carbon fibre prepreg composites. Solutions have included moulding in two halves and bonding afterwards, dissolvable cores, soft inflatable bladders, and low-definition printed filament tooling. However, these processes have problems with leaks, questionable internal face control and consolidation of the finished composite part, or excessive, costly mandrel preparation.

The benefits of Graphite Additive Manufacturing’s SLA process are said to include:

Production of fully air-tight, high-definition printed hollow mandrels.
Mandrels are rigid at room temperature for accurate lay-up and material de-bulks.
Material softens at 80°C to allow mild inflation under pressure – providing
consolidation against external mould for excellent moulding quality.
Demoulding is quick and safe – can be removed by pulling out when warm and deformable without the need for chemicals.
Suitable for 135°C (and even 180°C) cure cycles with autoclave pressure applied.
Machine build volume of 500 mm x 500 mm x 580 mm, allowing large pipes and complex geometries to be built in one or two sections.
The process can produce composite parts up to 1.5 m long.

A high-flow intake pipe forming a visual and high-performance under-bonnet upgrade to a special edition model from a high-end automotive OEM has been produced. Graphite reports than an exceptionally smooth internal surface for improved airflow even with the challenging geometry was achieved with its mandrel technology. Excellent material consolidation and overall part quality means there is no risk of boost-pressure leaks and no external finishing required. SLA technology helped produce a premium component with low weight, high strength and stiffness and was cost-effective for the relatively low volumes required.

Image provided by Graphite Additive Manufacturing

For more information visit: