SLA 3D Printing Services
XC Machining provides SLA 3D printing for US product teams. A UV laser cures liquid resin at 25 to 100 μm layers. Parts reach Ra 0.5 to 2 μm and hold ±0.1 to 0.2 mm. First parts ship in 1 to 3 business days with no tooling.
- All uploads are secure and confidential
What Is SLA 3D Printing at XC?
Stereolithography (SLA) cures liquid thermoset photopolymer resin in a vat. An ultraviolet laser traces each layer, 25 to 100 μm thick, and the part rises out of the resin one layer at a time.
The cure fuses each layer into a solid. That gives the smoothest surface of any polymer process at XC, Ra 0.5 to 2 μm as printed, with sealed walls.
Online SLA Quotes for US Teams
Upload a design on the site and get a quote back within 12 hours. XC Machining prints SLA parts in Dongguan for US teams. Engineers pick the resin, orientation and finish with you, and parts ship worldwide by express courier.
SLA 3D Printing Tolerances
Accuracy depends on part size and layer height. The table lists the limits XC works to.
| Item | Specification |
| Precision tolerance | ±0.1 mm up to 100 mm in XY, then ±0.2% of nominal |
| Z-axis tolerance | ±0.1 to 0.2 mm, set by the layer height |
| Layer thickness | 25, 50 or 100 μm |
| Minimum wall thickness | 0.5 mm |
| Minimum part size | 10 × 10 × 1 mm |
| Maximum part size | 335 × 200 × 300 mm standard, 736 × 635 × 533 mm large format |
| Production volume | Prototyping 1 to 100 pieces, low volume 101 to 10,000, high volume above 10,001 |
| Lead time | 1 to 3 business days for prototypes, 3 to 7 days for batches or multi-step finishing |
SLA Wall and Size Limits
Walls decide whether a resin part survives cleaning and holds fluid. Size decides whether it prints in one piece. Use these limits when you model the part.
| Goal | Limit | What happens |
| Printable part | Wall of 0.5 mm or more | The absolute floor. DFM flags anything under 1.0 mm |
| Watertight seal | Wall of 1.5 mm or more | Confirmed by pressure testing |
| Pressurized fluid | Wall of 2.0 mm or more | Adds margin for leak-tight flow paths |
| Fine detail | Features under 1.0 mm | Resolve at 25 μm layers, including logos and textures |
| Cosmetic faces | Face the build away from supports | Support-side faces run Ra 1.5 to 4 μm |
| Parts over 335 × 200 × 300 mm | Large format or split and bond | Splits are bonded and seam-sanded |
If the part is a strong nylon bracket and not a smooth model, SLS 3D printing suits it better.
Why Choose XC for SLA Printing
XC SLA parts reach Ra 0.5 to 2 μm and hold ±0.1 to 0.2 mm at 25 to 100 μm layers. Six resins cover display, functional, clear, flexible, high-heat and casting jobs. DFM review takes 12 hours, and parts ship in 1 to 3 business days.
As printed, SLA beats FDM at Ra 6 to 16 μm and SLS at Ra 6 to 12 μm. It also beats MJF at Ra 4 to 8 μm. After sanding and priming it reaches Ra 0.1 to 0.4 μm, close to molded ABS. Use it for investor demos, product photos and master patterns for silicone molds.
UV curing fuses each layer into a continuous solid, so there is no gap between layers. Walls of 1.5 mm or more seal under pressure testing. Teams use SLA for fluid models, microfluidic prototypes and waterproof enclosures where FDM or SLS parts would leak.
The six resins span brittle display models to 220°C mold inserts. Engineers recommend one during DFM review, based on load, heat, optics and casting needs. The Materials section below lists each grade.
Upload an STL or STEP file. Engineers check wall thickness of 1.0 mm or more and plan supports to protect cosmetic faces. They also set build orientation, pick the resin and plan the sanding, painting or clear coating needed to hit your target Ra and color.
Finishes for SLA Printed Parts
SLA parts leave post-curing with a smooth, slightly matte surface. Most display work needs no more. The table lists the steps XC adds. Our surface finishing page has the wider list of coatings and finishes.
As printed to Ra 0.5 to 2 μm. Smooth, slightly matte. Faces that touched supports run Ra 1.5 to 4 μm from witness marks.
Sanding to Ra 0.1 to 0.4 μm. Progressive grits from 120 to 2000 remove layer lines and support marks. Wet sanding at 2000 gives a semi-gloss finish.
Priming and painting to Ra 0.1 to 0.4 μm. Automotive primer and polyurethane or epoxy topcoat, 80 to 140 μm in total, in RAL or Pantone colors. Adds ±0.04 to 0.07 mm.
Clear coating to Ra 0.1 to 0.2 μm. Restores clarity on clear resin after polishing. Light transmission runs 85 to 92%, depending on the resin.
Optical polishing to Ra 0.1 μm or less. Diamond paste from 3 μm to 0.5 μm on clear parts under 50 mm. Adds 1 to 2 business days.
Dyeing and tinting (color only). White resin soaks in heated dye 0.1 to 0.2 mm deep. Clear resin takes amber, blue, green or red tints.
Clear coating suits lens prototypes, light guides and headlight covers. Dyeing suits medical mockups and consumer color studies.
SLA Resins We Print
XC prints six resin families. Ask for the resin datasheet before you design to a strength figure. Our materials page covers every process and grade.
The display model resin. It reaches 65 MPa tensile and 5 to 10% elongation, and it is brittle.
Built for snap fits and functional enclosures. It reaches 55 MPa tensile and 25 to 35% elongation.
Optical-grade clarity for lenses and fluid models. It reaches about 60 MPa tensile.
A soft grade at Shore A 80 with 70 to 130% elongation. It suits gaskets and living hinges.
Heat deflection temperature of 220°C makes it the pick for mold inserts.
Burns out with 0% ash. It makes investment casting masters for jewelry and precision metal parts.
Our Stereolithography (SLA) Prototype Manufacturing Capabilities
Provides injection molding for prototypes and custom parts, emphasizing expert support, competitive pricing, and faster production cycles.
Get reliable vacuum casting services for high-quality prototypes and production parts at competitive prices. XC Machining offers highly detailed casting parts with consistent quality.
Uses cutting, bending, and forming techniques to produce precision metal components suited for industrial, commercial, and manufacturing applications.
Specialist Industries
Bring Your Designs to Life with XC Machining
Experience precision engineering with XC Machining. From detailed prototypes to high-volume production, we’re here to turn your concepts into reality. Contact us today to discuss your project needs!
- 50+ CNC machines in-house
- 60+ materials in stock
- 120+ countries shipped
- 15+ DFM engineers on staff
- All uploads are secure and confidential
SLA 3D Printing FAQs
What tolerance does XC hold for SLA 3D printed parts?
XC holds ±0.1 mm on SLA parts up to 100 mm in XY. Above 100 mm, tolerance is ±0.2% of nominal. Z-axis tolerance is ±0.1 to 0.2 mm, set by a layer height of 25, 50 or 100 μm. UV post-curing adds 0.3 to 0.6% shrinkage, so XC pre-scales critical dimensions to offset it.
What is the smoothest finish SLA can reach?
As printed, SLA reaches Ra 0.5 to 2 μm, the smoothest of any polymer process XC offers. Sanding from 120 to 2000 grit and priming brings it to Ra 0.1 to 0.4 μm, close to molded ABS. Diamond polishing on clear resin reaches Ra 0.1 μm or less. FDM prints at Ra 6 to 16 μm and SLS at Ra 6 to 12 μm.
What resins are available for SLA at XC?
XC prints standard resin at 65 MPa for display models, and tough ABS-like resin at 55 MPa and 25 to 35% elongation for snap fits. Clear resin gives optical clarity for lenses. Flexible resin is Shore A 80 for gaskets and hinges. High-temperature resin holds 220°C for mold inserts, and castable resin burns out clean.
Does SLA 3D printing produce watertight parts?
Yes. SLA parts with walls of 1.5 mm or more are watertight, because UV curing fuses each layer into a pore-free solid. Use walls of 2.0 mm or more for pressurized fluid. Teams use SLA for microfluidic prototypes, waterproof enclosures, fluid models and biomedical flow-path tests, where porous FDM or SLS parts would leak.
What is the maximum part size for SLA at XC?
The standard SLA build volume is 335 × 200 × 300 mm. Large-format SLA builds up to 736 × 635 × 533 mm. Parts beyond that are split into sections, bonded with structural adhesive and seam-sanded into one smooth piece. Splitting is routine for architectural models, large display models and full-scale industrial design mockups.
What is the lead time for SLA parts at XC?
Prototype quantities of 1 to 10 parts in standard or tough resin ship in 1 to 3 business days. Batches of 10 to 50 or more parts, or parts with sanding, priming, painting or clear coating, take 3 to 7 days. Rush delivery of 24 hours covers simple standard resin parts. DFM review and quote return within 12 hours of upload.
When should I choose SLA instead of SLS or FDM?
Choose SLA when surface finish matters most, such as for demos, photos or casting masters. Choose it for ±0.1 mm tolerance against ±0.3 mm for SLS, for clear parts, for watertight walls, or for fine detail under 1.0 mm. Choose SLS or FDM when the part must be tough, heat resistant or large.
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