Xometry’s vapor smoothing service provides low-cost finishing for additive-manufactured parts, resulting in a surface finish that rivals injection molding.
3D printing is one of the best ways to get low-volume production goods. However, plastic 3D printing tends to have one significant trade-off: parts with coarse surface finishes. Powder bed fusion processes like selective laser sintering (SLS) and HP Multi Jet Fusion (MJF) leave a matte, sugar cube-like surface finish. Fused deposition modeling (FDM) shows distinct layer lines. For the last 30 years, post-process surface finishing like abrasive media tumbling, hand finishing, or coatings have minorly improved the surface finishes of 3D printed parts. If cosmetics are a priority, engineers may choose other processes entirely like injection molding, machining, or urethane cast parts.
With the introduction of chemical vapor smoothing, a technology that smooths the surface of 3D prints and enhances mechanical performance via vaporized solvents, 3D printed plastics are now more suitable than ever for low-volume production. Chemical vapor smoothing works on most 3D printed polymers and elastomers, including over twenty 3D printing materials available through Xometry. Read on to learn more about chemical vapor smoothing, its benefits, and its applications.
Xometry has adopted AMT’s PostPro3D chemical vapor smoothing technology. Unlike physical smoothing processes such as sanding or media tumbling, vapor smoothing does not remove material on the workpiece. Instead, a solvent vapor is introduced into a sealed processing chamber with the parts. Although the solvent is the same, different processing parameters are used for different materials and geometric features. Parts are racked, or hung, in a 600 x 400 x 400 mm chamber to maximize the surface exposure to the vapor. The vapor clings to the part surface where it creates a controlled chemical melt. This melt reduces the surface peaks and valleys by redistributing material and evening the surface. The melt also has the effect of enhancing shine.
Once the parts are finished, the chamber is heated to evacuate the chemical vapor to a collection vat. No residue is left on the parts. Smoothed parts are then ready for shipping or for another secondary process such as dyeing.
|Material Name||Process||Quoting Process|
|Nylon 12||SLS, HP MJF||Instant Quote|
|Nylon 12, Glass Bead||SLS, HP MJF||Instant Quote|
|Nylon 11||HP MJF||Instant Quote|
|Thermoplastic Urethane, TPU 88A||HP MJF||Instant Quote|
|Polypropylene (PP)||HP MJF||Requires Review|
|Nylon 11 EX||SLS||Requires Review|
|Nylon 12, Carbon-Filled (CF)||SLS||Requires Review|
|Nylon 12, Aluminum-Filled (AF)||SLS||Requires Review|
|Nylon 12, Mineral-Filled (HST)||SLS||Requires Review|
|ABS-M30 (6 colors)||FDM||Requires Review|
|ASA (10 colors)||FDM||Requires Review|
|Nylon 12||FDM||Requires Review|
|Polycarbonate (PC)||FDM||Requires Review|
|ULTEM 1010||FDM||Requires Review|
|ULTEM 9085 (2 colors)||FDM||Requires Review|
The table above shows every Xometry material that can be chemically vapor smoothed, including those which may require a manual review. You can get an instant quote on these materials by selecting "Vapor Smoothing" under the "Finishes" drop-down menu.
You can get instant pricing and lead times on vapor smoothing in the Xometry Instant Quoting Engine℠ based on the process, material, quantity, and part geometry for the most popular HP MJF and SLS materials. Because the process is batch-based, costs are relatively low per part and will decrease with increased order volumes. Xometry typically adds between 1-5 business days to lead times for vapor smoothing.
Xometry will manually review vapor smoothing orders for fused deposition modeling and specialty materials like SLS high-performance blends, Nylon 11 EX, Nylon 12 AF, Nylon 12 HST, and Nylon 12 CF. Please select "Custom" as your finish option and submit the quote for an expert review.
Vapor smoothed parts have improved cosmetics and are comparable to injection molding surface finishes. Standard SLS parts typically have a surface roughness greater than 250uin Ra, but with chemical vapor polishing can improve to below 125uin Ra and as low as 40uin Ra. In some studies, chemical vapor smoothing improved material surfaces by 800%-1000%. It is important to note that chemical vapor smoothing re-distributes surface material to provide a sealed, smooth surface but it does not create a polished surface. There will still be visible surface topology and minimal layer lines.
Chemical vapor smoothing can significantly increase the viability of 3D prints in food processing, medical devices, and consumer products, and is recommended for end-use applications in these industries. Notably, vapor-smoothed nylon 12 3D prints effectively reduce bacterial attachment and growth compared to standard nylon 12 3D prints. Studies have shown that vapor-smoothed SLS and HP MJF parts conform to and pass multiple biocompatibility and safety tests.
Other benefits of chemical vapor smoothing include:
Surface roughness of chemical vapor smoothed SLS part (left) next to a standard finish part (right)
|Food Contact Test||PASS||SLS printed PA-12 parts chemically vapor smoothed with PostPro3D does not affect the consumer health nor influence the quality of food.||According to regulation (EC) 10/2011 Annex V, Chapter 3, Table 3, OM 3, 2 hours at 70°C. DS/EN1186-01:2002 DS/EN1186-03:2002 DS/EN1186-14:2002|
|Skin Irritation Test||PASS||SLS printed PA-12 parts chemically vapor smoothed with PostPro3D did not cause a skin-irritating effect.||ISO 10993-10 (2013); ISO 10993-1 (2018); OECD TG 439|
|Cytotoxicity Test||PASS||MJF printed PA-12 parts chemically vapor smoothed with PostPro3D did not cause a cytotoxic effect.||ISO 10993-5 (2009); ISO 10993-1 (2010); ISO 10993-12 (2012)|
|Microbiological Test on MRSA Bacteria||PASS||MJF printed PA-12 parts chemically vapor smoothed with PostPro3D show a reduction of bacterial growth quantified as 99.88% against MRSA||MOD ISO 22196: 2011|
|Microbiological Test on E. coli Bacteria||PASS||MJF printed PA- 12 parts chemically vapor smoothed with PostPro3D show a reduction of bacterial growth quantified as 99.78% against E. coli.||MOD ISO 22196: 2011|
The chemical used for vapor polishing is safe and the closed-loop process of AMT’s PostPro3D system ensures that there is no extra residue left on the parts after smoothing. In fact, studies have shown that vapor-smoothed SLS and HP MJF parts conform to and pass multiple biocompatibility and safety tests concerning food contact, skin irritation, cytotoxicity, and bacterial growth. The results are summarized above and more details can be found in this AMT PostPro3D document on safety certifications.
Enhanced cosmetics, better coloration, and sealed surfaces can make vapor smoothed 3D prints showstoppers.
Vapor smoothing does not significantly increase lead times, allowing for highly functional parts in record times.
Vapor smoothing is a bulk finishing process for production 3D printing, making it an ideal way to build large quantities of customized parts.
Free shipping on all 3D printing
Choose from millions of possible combinations of materials, finishes, tolerances, markings, and certifications for your order.
Get your parts delivered right to your door without the hassle of sourcing, project management, logistics, or shipping.
We back every part we ship with the Xometry Quality Guarantee. Job One at Xometry is making your custom parts to your specifications.