Manufacturing Tools: Modular Fixtures
A modular fixturing system is a versatile alternative to a single–purpose, dedicated fixture.
Constructed from a kit of interchangeable components, the modular fixture is easily reconfigured
for any workholding application. When not in use, the fixture can be dismantled for convenient
Modular systems are ideal for intermittent or one–time use. They are commonly used to:
- Stage parts for CMM inspections
- Hold work pieces during machining
- Position parts when bonding or assembling
For these applications, the modular system saves time and reduces cost.
While the majority of the modular fixture is constructed from standard components, the interface
is custom made with FDM technology on a Fortus 3D Production System. At each support point,
an FDM contact element acts as the transition from the part’s surface to the fixture’s grid plate,
pillar or beam. These contact elements can be manually designed in CAD, but this design effort
may take more time than that to construct the FDM elements.
The Magics RapidFit module provides a faster and easier way to create the STL files for the
custom FDM elements. This software, created by Materialise, automates the digital design
process. With just a few mouse clicks, the files are ready for building on a Fortus system. Just a
few hours later, the fixture is assembled and ready for use.
1. Design Fixture:
Option A - Use CAD program
Option B - Use Materialise RapidFit
- 1. Import the STL file of the part to be fixtured into Magics RapidFit. Also, import or create
the files for the modular components of the fixture.
- 2. Begin the design by positioning the part, grid plate, pillars and beams in the desired
- 3. To create the custom contact elements, select the fixture support points and specify
the type of contact to use and the direction to the grid plate. The RapidFit software will
automatically create the contact elements and label each with a location and part name.
RapidFit also documents the assembly plan.
2. Manufacture Fixture Components:
Import the STLs of the contact elements into Insight and prepare them for building. All Fortus
materials and build styles may be used. However, ABS–M30, PC, PC-ABS with soluble supports
and a solid fill are recommended.
When the build is complete, simply remove the support structures and proceed to assembly.
3. Construct Fixture:
Gather the grid plate, pillars, beams and FDM components. Following the assembly instructions,
place the FDM components on the beams and pillars, and connect the beams to the grid plate.
The modular fixture is now ready for its inspection or manufacturing application.