3D Printing - Display Parts Finishing Solutions - Sealing FDM Parts
FDM (Fused Deposition Modeling) 3D Printing technology is one of the most cost effective and time saving processes on a manufacturing market for many applications. FDM is an additive manufacturing process which builds parts or models layer by layer on a 3D printer's platform based on CAD files. Having an FDM part will enable significant performance improvements since they eliminate all geometrical restrictions. Using FDM parts in functional prototyping and direct digital manufacturing processes is no longer an impossible. A number of different sealing methods have been developed and validated for FDM parts, such as taking advantage of the Fortus Smoothing Station, Epoxy Coating, Epoxy Infiltration, Dipping, Painting and Filling.
How it works
There are many methods to seal an FDM part and many characteristics to consider when choosing the best approach. To assist in selection, Stratasys evaluated the cost, time, difficulty, geometry limitations, maximum part size, viscosity, accuracy retention, maximum pressure, chemical resistance and temperature sensitivity of five common sealing methods.
The Finishing Touch Smoothing Station seals a part’s surfaces by exposing them to a vaporized smoothing agent inside a chamber. The Smoothing Station is very easy to use and preserves dimensional integrity. Its use is limited to applications with no higher than atmospheric pressure and temperatures at or below 212 °F (100 °C). The Smoothing Station is often selected when electroplating parts, using them as patterns for investment casting or producing functional prototypes of liquid-holding geometries such as bottles or cooling lines in molds.
Hysol E-20HP is a two-part epoxy that is dispensed with a mixing gun and brushed onto the part in small sections. This method does not require an investment in equipment, and the end result is ideal for harsh operating conditions. The coating will maintain an airtight seal up to a pressure of 65 psi (448 kPa), can withstand temperatures that match or exceed those of FDM materials and is resistant to many chemical agents. It can be difficult to seal large or intricate parts with epoxy. Inaccessible features such as internal channels cannot be sealed. The thickness of the epoxy combined with the manual application reduces dimensional accuracy of the part. Hysol E–20HP may be used on any of the currently available FDM materials.
BJB epoxy resin (TC–1614) penetrates the surface of porous and semi-porous parts. FDM parts are immersed in the resin and a vacuum is drawn to infiltrate the epoxy into the part. In addition to a vacuum chamber, an oven is needed to pre-heat and cure the epoxy. Epoxy infiltration offers an airtight and watertight seal up up to 65 psi (448 kPa). Parts sealed by this method also withstand high temperatures and are chemically resistant. The sealing process is straightforward and can be completed in less than three hours but is somewhat expensive due to the cost of the epoxy. When care is used in the infiltration process, there is little change in the part’s dimensional accuracy. BJB TC–1614 may be used on any of the currently available FDM materials.
Dipping FDM parts in solvent can substitute for using the Smoothing Station when it is unavailable or the part exceeds the chamber capacity. All characteristics are similar to those of the Smoothing Station except that dimensional accuracy is lower. The solvent melting action is quick and aggressive, so dimensional accuracy is difficult to control. As with the Smoothing Station, the use of this method should be limited to low–temperature, atmospheric-pressure applications. Dipping is suitable for all ABS-based FDM materials.
Painting and Filling
When FDM parts need only partially sealed surfaces, a few coats of paint and a little body putty can be an inexpensive option. Since this is a manual operation, the accuracy and quality of the end product is influenced by the skill and care of the technician. The advantages of this option include low cost, short cycle time and ease of application. Its disadvantages are lack of an airtight seal and inability to resist high temperatures or chemicals. This method can be used to reduce the porosity of FDM tooling used in thermoforming, for example.
The Proto3000 Advantage
The Proto3000 manufacturing facility is equipped with the Fortus Production Series 3D printers to create FDM materials. Our manufacturing technicians are capable of creating high-quality FDM parts which require different 3D printing solutions. Call the Proto3000 Services Team NOW for your display part finishing projects. Contact us for further information on how we can help you with this solution. If you want to speak to a LIVE PERSON - CALL 1-888-88-PROTO (77686).
The Technology Used for Our Display Part Finishing Solutions
Fused Deposition Modeling (FDM) Technology
Using FDM technology allows affordability and durability by printing concept models with production-grade thermoplastics.
FDM 3D Printers are office friendly and they produce small models in hours and large models in days. The FDM printed models can be drilled, sanded and painted according to your preference to create a perfect finishing of your prototype.
PolyJet 3D Printing Technology
As a 3D printing process, this technology produces amazingly realistic models. The printing technology builds accurate models by incorporating multiple materials into one automated part to create prototypes that look and feel like finished products. With fine details, smooth surfaces, rigid housings, soft-touch buttons, lettering, rubberlike seals and even clear components, your models can look the part at a trade show, a presentation or even during a sales pitch.