Vapor smoothing for SLS nylon parts
Vapor smoothing exposes a finished nylon part to a controlled solvent vapor that melts and reseals its outer skin. The grainy SLS texture becomes smooth and closed, so parts feel closer to injection molded, shed dirt and clean easily. It costs $4 per part plus $0.02 per cm² of surface and adds one business day.
- Price
- $4 + $0.02/cm²
- Adds
- 1 business day
- Materials
- Nylon 12 · 11 CF pilot
- Cycle
- 1.5 to 3 hours
How it works
After printing and media blasting, parts go into a sealed chamber. A solvent vapor condenses on the surface, softens the outermost layer of nylon so it flows into the powder texture, then evaporates. Nothing is sprayed or sanded, so internal surfaces and fine features are smoothed too, as far as the vapor can reach.
We run a DyeMansion VX1, an entry-level vapor smoother built for PA12, PA11 and TPU. Its chamber holds 24.6 liters of parts, a cycle takes 1.5 to 3 hours, and each cycle uses under 1 kWh of power.
What changes
| Property | Media blasted | Vapor smoothed |
|---|---|---|
| Surface | Matte, slightly grainy | Smooth, sealed, satin to semi-gloss |
| Dirt and moisture | Porous surface holds dirt | Sheds water and wipes clean |
| Feel | Textured | Close to injection molded |
| Sharp edges | Crisp | Slightly rounded |
| Lead time | Standard | One extra business day |
When it's worth it
- Parts people hold, wear or see: handles, cases, wearables, consumer products.
- Parts that get dirty or wet and need to be wiped down.
- Short production runs that should look molded, not printed.
When to skip it
- Tight-tolerance mating features, threads and press fits, where edge rounding matters.
- Hidden internal parts nobody touches.
- Tiny, thin features under 1 mm, which can soften too much.
Design tips
- Keep walls even and 1.2 mm or thicker so every surface smooths at the same rate.
- Avoid knife-edge corners; a 0.3 mm or larger fillet keeps the shape you drew.
- Mark critical dimensions in your order notes and we'll measure them after smoothing.
What it costs
| Part | Material | Standard | Vapor smoothed |
|---|---|---|---|
| Mounting bracket, 60 × 20 × 40 mm | Nylon 12 | $8.78 | $13.94 |
| Electronics tray, 100 × 70 × 40 mm | Nylon 12 | $20.55 | $32.50 |
The tray has about 4× the surface of the bracket, which is why its smoothing costs more.
Questions
Does vapor smoothing change dimensions?
Only slightly: sharp edges round a little as the surface flows. Mark critical dimensions in your order notes and we measure them after smoothing.
Can dyed parts be smoothed?
Yes. We dye first and smooth second, which gives a deep, even black.
Is a smoothed part waterproof?
It is sealed and sheds water far better than raw SLS nylon. For pressure-tight parts, ask us to test a sample first.
Which materials can be smoothed?
Nylon 12 as a standard option. Carbon fiber Nylon 11 is a pilot, so we confirm the finish on your part first. Resin parts come off the printer smooth and don’t need it.