---
title: "Protolabs: Flame-Retardant UL94 V-0 Parts | AMT PostPro"
description: "How Protolabs combines HP MJF with PostPro vapor smoothing to make flame-retardant automotive parts with UL94 V-0 compliance and a refined surface."
canonical: https://amtechnologies.com/resources/case-studies/flame-retardant-3d-printed-parts/
updated: 2026-10-06
type: case-study
---
Case study · Automotive & motorsport

# Flame-retardant 3D-printed parts with UL94 V-0 compliance

Making flame-retardant 3D-printed parts for demanding automotive uses takes more than the right material. Protolabs combines HP Multi Jet Fusion with PostPro vapor smoothing to produce flame-retardant components with UL94 V-0 compliance and a surface that suits end use.

[Read the full case study (PDF, opens in a new tab)](https://6983077.fs1.hubspotusercontent-na1.net/hubfs/6983077/Website/Case%20Studies/AMT_CS_Protolabs.pdf) [Test your parts, free](https://amtechnologies.com/test-your-parts/)

Published Jun 3, 2026 Free download

![Protolabs production floor: a row of HP Multi Jet Fusion printers under extraction ducts](https://amtechnologies.com/img/resources/cs-protolabs-800.webp)

Protolabs production facility with HP MJF printers.

- **Customer**: [Protolabs](https://www.protolabs.com/)
- **Industry**: [Automotive & motorsport](https://amtechnologies.com/industries/automotive/)
- **Application**: Flame-retardant automotive components
- **Printing**: HP Multi Jet Fusion
- **Material**: HP 3D HR PA 12 FR
- **Finishing**: [PostPro vapor smoothing](https://amtechnologies.com/products/vapor-smoothing/)
- **Published**: Jun 3, 2026

## The requirement

Components often need UL94 V-0 compliance together with airtight performance and a high-quality surface finish. This application called for parts that withstand internal pressure and strict automotive safety requirements, with a surface comparable to injection-molded parts.[1]

## The approach

Protolabs validated HP 3D HR PA 12 FR printed on [HP Multi Jet Fusion](https://www.hp.com/us-en/printers/3d-printers/products/multi-jet-technology.html) together with [PostPro vapor smoothing](https://amtechnologies.com/products/vapor-smoothing/). By reducing surface porosity and improving overall surface integrity, vapor smoothing helped unlock performance that as-printed parts alone could not reach.[1]

The full case study covers the testing process, the surface improvements and how vapor smoothing helps enable certified end-use additive manufacturing applications.

Result

Reduced surface porosity on UL94 V-0 flame-retardant parts[1]

Full case study

The complete story as a PDF. Free, after a short form.

[Download the PDF (opens in a new tab)](https://6983077.fs1.hubspotusercontent-na1.net/hubfs/6983077/Website/Case%20Studies/AMT_CS_Protolabs.pdf)

Related

- [PostPro vapor smoothing](https://amtechnologies.com/products/vapor-smoothing/)
- [Automotive & motorsport applications](https://amtechnologies.com/industries/automotive/)
- [All case studies](https://amtechnologies.com/resources/case-studies/)

Test your parts

## Send us a part. See it smoothed.

We vapor smooth your own parts and send them back with the results. No cost to evaluate · Parts returned · Typical turnaround 2–3 weeks[2]

[Test your parts, free](https://amtechnologies.com/test-your-parts/) [See the systems](https://amtechnologies.com/products/vapor-smoothing/)

## Sources

1. [Flame-retardant 3D-printed parts with UL94 V-0 compliance (Protolabs case study)](https://amtechnologies.com/resources/case-studies/flame-retardant-3d-printed-parts/) · AMT · Jun 3, 2026
2. [PostPro benchmarking: send us your 3D printed parts](https://benchmarking.amtechnologies.com/) · AMT · read Oct 6, 2026