What are the advantages of SLA?

With five different 3D printing technologies in-house, we are well aware of the pros and cons of each. We often recommend SLA (stereolithography) to customers, so we are frequently asked ‘What are the advantages of SLA?’

Versatility

SLA is a very versatile 3D printing technology thanks to the inherent high accuracy and good surface finish, choice of materials and range of finishing options – all of which are discussed in more detail below. Also, because of the way SLA builds parts by curing a liquid resin, parts are not porous.

SLA’s versatility means it is suitable for a broad spectrum of additive prototyping applications including concept models, functional prototypes, presentation models and master patterns for vacuum casting. In certain circumstances, SLA can also 3D print end-use parts, sometimes referred to as additive manufacturing.

We have seven SLA machines and the largest has a build envelope of 508 x 508 x 534 mm, so we can 3D print anything from small to relatively large parts.

Accuracy and surface finish

We quote a general tolerance of ±0.5 mm on SLA parts, though the tolerance achieved is often tighter. Our Neo SLA 3D printer has a beam size of 80-750 µm, and our Projets have a beam size of 75-750 µm. Layer thickness is usually 0.1 mm but we can 3D print with 0.05 mm layers if required.

This combination of excellent resolution and fine layer thickness results in highly detailed parts with a very good ‘as printed’ surface finish that is ready for painting if required. Compared with other 3D printing technologies such as SLS or FDM, the accuracy and surface finish of SLA parts are considerably better.

Material choices

Today you can buy dozens of different materials for SLA but we have selected four, with AMX-300, that suit most of our customers’ requirements (and we offer alternative 3D printing technologies if customers need different material properties). All our SLA materials have good strength and rigidity, with better isotropy than SLS or FDM 3D printed materials.

By offering four materials, we can offer a fast turnaround because it would be time-consuming to switch between materials on the SLA 3D printers. Furthermore, every material behaves slightly differently, so by becoming very familiar with four, we can be confident of getting parts right first time.

The materials we use are Accura ClearVue (a water-clear material with properties similar to polycarbonate), Accura 25 (similar to polypropylene), Accura Xtreme (similar to ABS) and AMX-300.

Depending on the material, finish and operating environment, these materials have good long-term performance, which makes them suitable for end-use parts.

Approved for patient contact

One of the materials we use with our SLA 3D printers, Accura ClearVue, has been tested and certified to USP Class VI. This means it is approved for patient contact applications – but talk to us first if this is a requirement for your parts.

Finishing options

The finish specified for SLA parts will depend on the application and, to some extent, the material. Parts can be supplied as-printed, or with a light bead blast finish, sanded, polished, or painted. We can also apply a soft-feel rubberised coating, and a blackout/EMI/RFI coating to internal surfaces. Accura ClearVue parts can be polished to give a glass-like appearance, and subsequent vacuum metallisation results in a mirror-like surface – such as for prototype car lamps.

In addition, SLA parts can be drilled and tapped to accept threaded fasteners, or we can install inserts for smaller screws or for joints that need to be assembled and disassembled multiple times.

Speed

SLA is fast enough that we can ship parts the next working day by means of our Express 3D printing service. We do not compromise on quality to achieve this rapid turnaround but we do restrict the range of finishing options.

Alternatively, we offer a Standard service, with parts shipped in three working days, which allows time for other finishes to be applied. If budgets are tight, our Economy 3D printing service ships parts in eight working days.

What are the disadvantages of SLA?

We like to give a balanced view of the services we offer. As well as the many advantages that SLA offers, there are also some disadvantages. Read our blog article on the disadvantages of SLA to find out more.

Talk to us

If you want to discuss your requirements for SLA 3D printed parts, contact us on 01763 249760 or request a quote.