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SLS nylon parts,
prototype to production batch.

Primofort runs a climate-controlled SLS floor in Dongguan — Formlabs Fuse and Farsoon large-format systems, seven SLS nylons in regular production, and engineers who answer with a real quote within 24 hours.

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9 production nylons up to 910 × 430 × 400 mm^CONFIRM Founded 2019 NDA on request

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Is SLS right for your part?

The honest version. SLS is excellent at a specific set of things and wrong for others — if your part belongs on a different process, we would rather tell you now than after you have paid for it.

Choose SLS when…

The part has to work, not just look right. Sintered nylon is a genuine engineering material — hinges, clips and housings survive real use.
The geometry is awkward. Unfused powder supports the part as it prints, so undercuts, internal channels and lattices need no support structures.
You need one now and hundreds later. The same process and the same material carry a prototype through to a production batch.
The part is large. Single-piece envelopes up to 910 × 430 × 400 mm^CONFIRM — sizes most bureaus have to split and bond.

Look elsewhere when…

You need full colour. SLS nylon prints in its natural grey or black. Full-colour models are a PolyJet job.
You want a glossy, sealed finish straight off the machine. Raw SLS is matte and slightly porous — vapor smoothing fixes this as a second step.
You need HP's published per-material tolerance tables. That is MJF, where the numbers are documented by the machine maker.
The part is tiny and needs very fine surface detail. Powder-bed processes have a practical floor on feature size; ask us and we will say so.

The process

How SLS actually works.

Three steps, repeated a few thousand times. No supports, no tooling — which is why the geometry can be as awkward as your design needs.

Spread a layer of powder

A recoater lays down a thin, even layer of nylon powder across a heated build chamber, held just below the melting point.

Fuse the cross-section

A laser traces your part's cross-section into the powder and sinters it solid. The platform drops one layer and the cycle repeats.

Cool, then unpack

The finished block of powder cools under controlled conditions, then parts are excavated, de-powdered and blasted clean. Loose powder is sieved and reused.

Farsoon polymer powder management system workflow diagram

Where the powder goes. Overflow and unfused powder are recovered, sieved, blended with new material and returned to the machine — which is why powder-bed printing wastes so little. Diagram by Farsoon, who build the large-format systems on our floor.

Diagram: Farsoon Technologies · farsoon-gl.com

Cutaway render of a top powder feed system above a build platform

Inside the build chamber. Powder is fed from above and levelled across the platform before each pass of the laser.

Image: Farsoon Technologies · farsoon-gl.com

Formlabs Fuse Sift powder recovery station

Recovery and sieving. Parts are excavated and surplus powder is reclaimed in a sealed station rather than swept up by hand.

Image: Formlabs · formlabs.com

The Fuse series, shown by the people who build it

Video: Formlabs · Fuse series Watch ↗

Materials

Seven SLS nylons, with the real numbers.

Published mechanical data from Primofort's material datasheet — not "contact us for specifications". Three of these open doors most buyers do not know they have:

Large format

910 × 430 × 400 mm^CONFIRM

Single-piece parts most bureaus would have to cut and bond. Housings, ducts and full-scale rigs, printed whole.

Biocompatible

YP120 white PA 12

Bright-white, biocompatible nylon — opens wearables and medical models, and rare at production scale.

Carbon fibre

110 MPa / 10 GPa

FS-YC6130CF carbon-fibre Nylon 6 — stiffness in metal-replacement territory, at nylon weight.

Material	Type	Tensile	Modulus	Elong.	HDT @0.45 MPa	Build size (mm)
Formlabs FYC110	Nylon 11	49 MPa	1.6 GPa	40%	182 °C	160×160×300
Formlabs FYC120	Nylon 12	50 MPa	1.85 GPa	12%	171 °C	160×160×300
Formlabs FYC120GF	Nylon 12 + glass fibre	38 MPa	2.8 GPa	7%	170 °C	160×160×300
FS-YC3201	Tough Nylon 12	42 MPa	1.45 GPa	20%	145 °C	910×430×400^CONFIRM
YP120	White PA 12 · biocompatible	46 MPa	1.84 GPa	13%	180 °C	420×420×450
YP120GF	Grey PA 12 + fibre	41.7 MPa	2.3 GPa	6.8%	168 °C	420×420×450
FS-YC6130CF	Nylon 6 + carbon fibre	110 MPa	10.0 GPa	2.5%	214 °C	420×350×350

Manufacturer-published figures from Primofort's material datasheet. Two further nylons (FS-YC220GF and FS-YC6140GF) are available on request. Full flexural data and datasheet downloads live on the materials page.

Tolerances & design rules

What SLS can actually hold.

There is no single industry tolerance standard for SLS, and the major bureaus disagree with each other by roughly 20%. So here is the honest position rather than a confident-sounding number.

Typical achievable: about ±0.3% of nominal, with a lower limit around ±0.3 mm — for well-designed parts, as commonly quoted by major service bureaus. Materialise publishes ±0.3% / ±0.3 mm; Protolabs quotes ±0.25 mm + 0.1% for SLS. These are service-bureau conventions, not machine specifications, and Formlabs publishes no tolerance figure for the Fuse series at all.

Tolerance for your geometry depends on part size, wall thickness, orientation in the build and the material. We confirm it against your drawing at quote — ask our engineers, and we will tell you if your tolerance is not achievable in SLS.

Design rules for SLS nylon

Published by Formlabs for the Fuse series. Follow these and your part prints first time.

0.6 mm

Minimum unsupported wall

Vertical walls. Horizontal: 0.3 mm. Thinner walls may warp or detach.

1.0 mm

Minimum hole diameter

Smaller holes may close off during printing. Design a pilot hole and ream it.

0.8 mm

Minimum pin diameter

Thinner pins risk snapping during powder recovery. Fillet where they meet the part.

3.5 mm

Escape holes

At least two per enclosed cavity, or it stays packed with unsintered powder.

Design rules: Formlabs — Fuse Series SLS Design Guide · formlabs.com

Proof, not promises

Not a broker. Our own SLS floor.

These two photographs were taken on our production floor in Dongguan. When you send us a part, these are the machines that print it — no outsourcing chain, no middlemen.

Formlabs Fuse SLS printer fleet at Primofort

Formlabs Fuse series — our production floor, Dongguan

Farsoon large-format SLS systems at Primofort

Farsoon large-format SLS — our production floor

The platforms we run

Manufacturer photography of the machine platforms on our floor — shown so you know exactly what your part is printed on.

Formlabs Fuse series

Compact SLS running Nylon 11, Nylon 12 and glass-filled Nylon 12, with a 160 × 160 × 300 mm usable envelope. The workhorse for prototypes and small batches.

Image: Formlabs · formlabs.com

Farsoon FLIGHT HT1001P large-format SLS system

Farsoon large-format SLS

The large-format side of the floor — where single-piece parts up to 910 × 430 × 400 mm^CONFIRM are printed whole rather than cut and bonded. That envelope is Primofort's own operating limit, not a figure Farsoon publishes.

Image: Farsoon Technologies · farsoon-gl.com

Machines on our floor

HP Stratasys

Primofort · 元城科技 — Room 303, Building 3, Huakecheng, Guanchang Rd, Dongcheng, Dongguan, Guangdong 523128, China

Get a quote

An engineer replies within 24 hours.

Real engineer, real quote. Not an auto-mailer — a person who has read your requirements and looked at your part.
Your IP stays yours. We send a secure link for CAD files; nothing is shared outside the project team. NDA on request.
We will tell you if SLS is wrong for your part. If MJF or PolyJet suits it better, we would rather say so at quote than after you have paid.

Prefer direct? service@primofort.com · +86 158 9991 6661 (WhatsApp)

SLS nylon parts,prototype to production batch.