Note:
Formlabs has sunsetted this material, and it is no longer available for purchase. For information about other Formlabs materials, visit Choosing the right powder.
WHITE PAPER
Using Polypropylene Powder
Using Polypropylene Powder
Polypropylene Powder is a high-performance material ideal for producing works-like prototypes and durable end-use parts. Components printed with Polypropylene Powder have a high ductility that allows for repeated bending and flexing while demonstrating excellent resistance to a wide range of acids, bases, organic solvents, fuels, and alcohols.
Note:
To learn more about the performance or specific material properties of Polypropylene Powder, refer to the Safety Data Sheet (SDS) and Technical Data Sheet (TDS). Always consult the SDS as the primary source of information to understand safety and handling of Formlabs materials.
Recommended for:
- Housing, cases, packaging prototypes
- Orthotics and prosthetics
- Automotive components
- Fixtures, tooling, jigs
Formlabs recommends using a 50% refresh rate and an ambient air printing atmosphere for Polypropylene Powder to achieve consistent results. Formlabs does not recommend printing with an inert gas atmosphere as it provides no known benefit for this material.
Comparison with other materials
See the table below for a comparison of relevant material properties:
| Polypropylene Powder | Nylon 11 | Nylon 12 | |
|---|---|---|---|
| Ultimate tensile strength (MPa) | 29 | 49 | 50 |
| Tensile modulus (GPa) | 1.64 | 1.60 | 1.85 |
| Elongation at break (%) - X/Y | 34 | 40 | 11 |
| Elongation at break (%) - Z | 16 | - | 6 |
| Flexural modulus (GPa) | 1.33 | 1.40 | 1.60 |
To learn more about the performance properties of Formlabs materials, refer to the library of material properties data sheets.
Printing with Polypropylene Powder
For the best results, follow Formlabs design specifications for SLS printing. Refer to the support article Starting a print (SLS) to open the model in PreForm, orient it, and send it to the printer.
Parts printed with Polypropylene Powder may have a rougher surface than parts printed in Nylon 12. To avoid warping, orient parts according to Formlabs recommendations.
The Fuse 1+ surrounds each printed part with Surface Armor, a semi-sintered shell. This alleviates potential thermal inconsistencies which may adversely affect a part’s accuracy. Surface Armor improves surface finish and is discarded during post-processing.
Before using Polypropylene Powder, check that the firmware on your Fuse Sift is up to date.
Best practices for sifting Polypropylene Powder:
- Allow parts printed to cool to room temperature before sifting.
- Check the sifter mesh for clogs and clean it with compressed air and a brush.
- Sift Polypropylene Powder using the 300 micron sifter mesh.
Between prints
Accumulated powder and condensed airborne particulates can cause print failures in future print jobs if not properly cleaned out after each print. Clean the following areas between prints:
- Inspect and clean the optical cassette
- Inspect and clean the IR sensor
- Clean the IR sensor housing
- Clean any powder that fell below or around the build chamber
- Clean both powder troughs and the area around the recoater’s path using a compliant vacuum with static dissipative components
- Inspect and clean the recoater if necessary
Cleaning the top of the print enclosure
Powder can accumulate at the top of the print enclosure, particularly on the runways, the areas between the powder troughs and the top of the build chamber. This excess powder may fuse and be dragged into the build chamber during subsequent prints. Vacuum this area thoroughly to help prevent print failures.
Vacuuming the troughs
Between prints, clean both troughs and the area around the recoater’s path using a compliant vacuum with static dissipative components. Use the vacuum, fitted with a small brush attachment or the flexible hose attachment, to clean all powder out of the troughs. If needed, use compressed air or a gas duster to remove powder from hard-to-reach areas. Check in particular for powder buildup along the inner walls and corners of the troughs.
Close the print enclosure door and move the flipper motors to dislodge powder for cleaning.
To move the flipper motors:
- Close the print enclosure door.
- On the touchscreen, tap the wrench icon. The Maintenance menu appears.
- Tap Motor Moves. The Motor Moves screen appears, which allows you to manually activate various motors in the print enclosure.
Caution:
Unless specifically advised, do not select any of the options in the Motor Moves menu while the print enclosure door is open or any objects are in the path of the powder handling mechanisms at the top of the print enclosure. Moving parts present a crushing or tangling hazard. If necessary, tap the Stop button on the touchscreen to stop a motor movement.
- Tap the CW, CCW, and Home arrows under the Flipper (Left) and Flipper (Right) headers to rotate the left and right flippers clockwise, counterclockwise, or back to their home positions. Repeatedly move the flippers and vacuum the powder troughs until they are clean. In particular, ensure that the inner edge of both powder troughs as well as any adjacent components are free of powder.
Cleaning the recoater
Move and inspect the recoater. If it appears coated with semi-sintered powder, clean the recoater before running another print.
To clean the recoater:
- On the touchscreen, tap the wrench icon. The Maintenance screen appears.
- Tap Motor Moves. The Motor Moves screen appears.
- Tap the < (Left) or > (Right) button under Recoater until you can view the recoater assembly.
- If the recoater is covered with semi-sintered powder, clean it with a PEC*PAD or other lint-free microfiber cloth wetted with ethanol.
Changing materials
Fuse 1 generation printers, the Fuse Sift, and related accessories are designed to be used with only one powder type at a time. Make sure to clean each device thoroughly, following Formlabs instructions, before switching powder types. Mixing powders can lead to print failures or permanent damage to the machine.
Using a dedicated build chamber for Polypropylene Powder is highly recommended. If using a build chamber that has previously printed with a different powder, the print bed assembly should be replaced in order to prevent failures due to stuck print beds. Please contact Formlabs Support or your certified service provider for guidance on replacing this component. Swapping out the print bed is most important when the previously printed material has a lower printing temperature than the new material, for example when switching from Polypropylene to Nylon 12.
If you plan to regularly print in multiple different materials, Formlabs recommends dedicating a separate printer, build chamber, and Fuse Sift for each material type for an easier workflow.
Polypropylene Powder melts at a lower temperature than other Formlabs SLS powders. As a result, be sure to thoroughly clean your printer, Fuse Sift, and build chambers when switching materials to or from Polypropylene. Follow the procedure listed below as applicable.
Consult the following support articles for additional information: