Large-Format SLA 3D Printing: Design Considerations

Large-format SLA 3D printing opens up new possibilities for engineers working on enclosures, housings, covers, and complex one-piece components. A build volume of 750 x 750 x 550 mm changes what is possible.

But designing for large-format SLA is not simply a case of scaling up a smaller part. The physics and post-processing realities require a different mindset.

Wall thickness behaviour at scale

As parts grow larger, wall thickness becomes more critical.

Thin walls may distort during curing. Excessively thick sections can introduce internal stresses. Uneven wall thickness increases the likelihood of:

• Warping
• Sink-like surface variation
• Dimensional movement during post-cure

A balanced, consistent wall thickness is usually more stable than heavily varied sections.

Orientation affects surface finish

In SLA printing, part orientation influences:

• Support placement
• Surface quality
• Post-processing effort
• Optical clarity

Large parts often require more supports. Strategic orientation reduces support scarring on cosmetic surfaces and simplifies finishing. Planning this at the design stage can significantly improve the final appearance.

Internal features and trapped resin

Large hollow sections must be designed carefully. Drainage holes and access points may be required to prevent trapped resin. Without proper escape routes, internal cavities can create curing inconsistencies or structural weaknesses. This is particularly important for enclosed housings or aesthetic display components.

Optical clarity vs visual clarity

For applications using clear resin, there is an important distinction:

• Optical clarity refers to true transparency through the material.
• Visual clarity refers to surface appearance and uniformity.

Layering, orientation, and finishing processes influence both. Large-format clear parts, printed using Matrix Clear (our large-format resin), often require sanding and polishing to improve transparency.

If transparency is not required, parts can still be printed in Matrix Clear and painted during post-processing, providing an opaque, production-style finish. This offers flexibility to achieve the desired look without changing material or adding extra cost.

Managing scale and stability

Large-format SLA 3D parts behave differently during curing compared to smaller components.

Considerations include:

• Thermal behaviour during post-cure
• Support density
• Structural reinforcement in flat areas
• Handling and transport after printing

Designing reinforcement ribs or subtle stiffening features can improve dimensional stability without compromising aesthetics.

When large-format SLA is the right choice

Large-format SLA is particularly effective for:

• Large cosmetic enclosures
• Display models
• Functional housings
• Complex shapes that would be costly to machine
• Parts requiring smooth surface finish

It bridges the gap between concept modelling and production tooling, offering speed and flexibility without committing to mould tooling.

As with any manufacturing process, early design input improves outcomes. Understanding how scale influences behaviour, and selecting the right material and post-processing approach, is key to achieving stable, high-quality large-format SLA parts.

Ready to explore how large format SLA 3D Printing could benefit your next project?

Visit our SLA 3D Printing page or contact us on 01763 249760 to discuss your requirements with our team.