What is Fused Deposition Modeling?

Fused Deposition Modeling (FDM) is a 3D printing/additive manufacturing technology used for modeling, prototyping, and production applications. FDM technology works with production-grade thermoplastics to build durable parts that are accurate, repeatable, and stable over time.

FDM fixtures, tools, and prototypes can withstand constant use on the production floor and perform well in punishing applications such as parts on the manufacturing floor and auto racing.

Monikers: Fused Filament Fabrication (FFF), filament extrusion, fused filament deposition, material deposition, FDM


How does FDM work?

3D printers using FDM technology extrude a heated thermoplastic filament through a nozzle, building the part layer-by-layer from the bottom up. The 3D printer heats the thermoplastic to a semi-liquid state and deposits the ultra-fine material along the extrusion path. FDM can deposit thicker or thinner layers to decrease build time (thicker layers) or decrease hand finishing time (thinner layers) due to the smoother surface. After each layer, the build platform indexes down to automatically prepare for the next layer.

To build angles, overhangs, and holes, FDM uses removable support material that acts as scaffolding to support the intricate build areas. Once completed, the support material can be broken away by hand or dissolved in detergent and water. The part is then ready to use.

How is FDM used?

3D printed FDM Airplane InteriorFDM materials offer many specialized properties including, but not limited to, toughness, electrostatic dissipation, translucence, biocompatibility, UV resistance, VO flammability, and FST ratings. This makes it perfect for demanding designers and engineers in aerospace, medical, electrical, consumer goods, and other industries.

FDM is commonly used to build aircraft interior components and ducting, and medical, consumer, industrial, and transportation prototypes and products. FDM can also be used for sacrificial tooling and internal mandrels.

What file format is used to process a part on an FDM system?

3D printing processes typically begin with a 3D CAD model that is then exported as an STL file. Other data inputs are possible through CT and MRI scans. There are also a variety of 3D scanners that can capture data and output STL files. The STL file is uploaded to the printer’s software program. From there, the user can hit the print button to grow the part or can use more advanced features for specialized parts.

What tolerances are Stratasys FDM 3D printers capable of holding?

Stratasys F123 series of 3D printersTolerances are a function of the system producing the part and the overall size of the part.

The F123 Series of 3D printers produce parts within an accuracy of ± 0.008 in. or ± 0.002 in./in. (± 0.200 mm or 0.002 mm/mm), whichever is greater.

The Fortus 380mc and 450mc large and small systems deliver an accuracy of ± 0.005 inch or ± 0.0015 in./ in. (± 0.127 mm or ± 0.0015 mm/ mm), whichever is greater.*

The Fortus 900mc parts are produced within an accuracy of ± 0.0035 inch or ± 0.0015 in./in. (± 0.089 mm or ± 0.0015 mm/ mm), whichever is greater.*

*Note: Accuracy is geometry dependent. Achievable accuracy specification is derived from statistical data at 95% dimensional yield.

What is the minimum thickness Stratasys FDM machines can print? (Also know as resolution)

The minimum thickness is 0.005 inches (0.127mm). The minimum layer thickness varies between material and machine. The layer thickness can vary between 0.005 inches (0.127mm) and 0.013 inches (0.330mm). The user can choose the desired thickness based on the printer, the application, part intent, and material capabilities.

What types of materials are available in FDM?

FDM uses the same materials aerospace, automotive, medical, and industrial sectors have relied on for injection molding with the ability to build complex geometries and the lower material consumption associated with 3D printing.

Stratasys offers 14 different types of thermoplastics that are dependent on the 3D printer. Some of the materials include ABS, ASA, PLA, ABS/PC blends, Polycarbonate, Nylon, Ultem. Each material has unique properties to fit the need of a variety of applications. Some even offer specialized properties like toughness, electrostatic dissipation, translucence, biocompatibility, UV resistance, VO flammability, and FST ratings.

FDM materials can be opaque to semi-transparent in multiple colors including blue, red, yellow, white, black, and tan.

3D Printed FDM ABSi Tailight Are there translucent materials available for FDM systems?

Stratasys offers two options for translucent materials called ABSi, PC-ISO, ASA, and PLA that are great for conceptual modeling, functional prototyping, and direct digital manufacturing.

Can I print a model with multiple colors?

FDM can accommodate multiple colors throughout a single part. Stratasys’ Insight software can pause the print job between any layers of the build so the user can load a canister of a different color and resume building on top of the previous color. This can only be done with various colors of the same material, and only on 3D printers that use the Insight software. Insight software comes with the purchase of a Fortus 3D Production System.

Can hollow or partially-filled models be printed using FDM materials?

3D Printed FDM box Users seeking to reduce cost/weight can use Stratasys’ Insight software to create different internal properties to allow for less material to be used.

Insight software allows a user to modify the interior model with solid and sparse fills as well, creating a custom fill by using advanced tools within the software.

For the F123 series, which comes with GrabCAD Print, users can choose the model’s interior make up. Three options are available: solid, sparse – high density, and sparse – low density.

Where can I get a prototype or small quantity produced without purchasing a 3D printer?

Easy, just contact the 3D printing experts at GSC. Get a quote within two business days by contacting 3dparts@gsc-3d.com today!