Large-format 3D printing is traditionally the remit of fused filament fabrication (FFF) 3D printers, which extrude plastic in layers with a mechanical print head. However, stereolithography (SLA) advancements now let you accurately create big models and put small series runs into production with liquid resin.
Large format SLA is a different type of solution to FFF, highly suited to small series production runs and manufacturing detailed, intricate models. SLA offers the best resolution and accuracy with a more refined surface finish.
The best 3D printer for the job is the Form 3L, which uses a proprietary technology called Low Force Stereolithography (LFS). LFS reduces peel forces and has a smaller laser dot size, enabling a support structure that is easier to remove.
This article reveals the top 10 benefits of large format SLA 3D printing, using the Form 3L as the benchmark for quality and ROI.
Let’s jump in!
1. Unlock rapid, small series production
The Form 3L’s large build platform enables the production of many smaller parts simultaneously, letting you print a series in around half the time of the Form 3. This unlocks time savings and lets you scale production.
Additionally, LFS creates supports that provide all the additional stability of regular supports without the long post-processing time.
You can speed up print times by orienting parts parallel to the build platform and hollowing out models, but you might not need to – the Form 3L is around twice as fast as standard SLA printers and fits more on the build platform.
2. Manufacture large parts in one go
With its 33.5 × 20 × 30 cm (13.2 × 7.9 × 11.8 in) build volume, the Formlabs Form 3L lets you additively manufacture large models in one sitting.
It has two 250 mW lasers that work independently, building layers with incredible precision to create true-to-design 3D models.
Unlike smaller printers, large format SLA printers let you produce large seamless parts rather than multiple smaller parts that join together to make a large model. This lets you simplify designs and reduce points of mechanical failure.
3. Print with unbeatable accuracy
It is no exaggeration to say that stereolithography offers unbeatable accuracy. SLA printers consistently produce high-resolution objects and are more accurate than FFF printers because the laser has a smaller focus size than a nozzle.
For example, the Form 3L has an XY resolution of 25 microns (this describes how precisely the printer can draw in the XY (horizontal) plane) with a laser spot size of 85 microns – ten times smaller than most FFF printer nozzles.
4. Harness multiple materials
SLA 3D printers use a UV laser to cure liquid resin into hardened plastic. There are over a dozen resins available, with Formlabs providing a library of over twenty materials spanning general-purpose to engineering and medical.
The mechanical properties of resins are distinct from thermoplastics, yet many are designed to mimic common plastics like ABS, PLA, Polycarbonate and TPU.
With a large volume SLA printer, you can produce complex, intricate models with similar mechanical properties to well-known hard and soft plastics. Additionally, you can use ESD-safe and high-temp materials for speciality projects.
5. Print around the clock
The only maintenance required during an SLA 3D printer operation is the manual swap out of resin cartridges. With the Form 3L, this takes less than two minutes – the resin cartridges clip in and out from the side.
Swapping out resin cartridges does not impact the printing process and only pauses a print for a few minutes.
Additionally, SLA 3D printers have no mechanical arms that can be affected by external movement, instead utilising a laser that bounces off mirrors. This is ideal for 24/7 printing in uncontrolled environments.
The Form 3L is built for 24/7, continuous 3D printing, with automated software, cloud monitoring and controls, and the ability to swap out replacement parts in-house. You do not need any specialised technicians to run the show.
6. Produce highly complex models
SLA offers several advantages over FFF, including speed, flexibility, and precision. However, the most significant advantage is that no mechanical print head restricts potential geometries – this unlocks new geometry and overhang opportunities.
LFS takes this one step further with a fast optics engine called the Light Processing Unit (LPU). The LPU emits a crisp laser spot with a spatial filter to catch stray light and a series of mirrors, ensuring the beam is delivered perpendicular to the print plane.
The result is a linear path for the laser, enabling more detail than ever before, as this photo shows (the Form 3 and Form 3L produce identical print quality):
Large format SLA 3D printing has the advantage over FFF when complex shapes and geometries are required. You can give models hollow spaces and complex internal structures that are impossible to produce with FFF.
7. Produce transparent parts
SLA has the unique ability to create transparent objects with few visible layer lines, which you can polish to produce optically clear models.
The Form 3L takes clear 3D printing further, with a flexible resin that significantly reduces peel forces for a more refined surface finish.
For example, the camera lens below was printed with LFS technology:
To create 100% clear prints, you need to use Clear Resin, which is engineered for optics and lighting applications. Printed parts also need sanding, polishing, and finally sealing with a spray clear coat (general purpose or automotive).
8. Achieve a smooth surface finish
If the rough surface finish and clear layer lines of FFF are not ideal, large format SLA 3D printers produce visibly smooth parts right out of the printer.
SLA parts have sharp edges, a smooth surface finish, and minimal visible layer lines – providing the correct print settings are chosen.
In some cases, unprocessed parts have a perfectly smooth finish with no requirement for post-processing. This surface quality is ideal for parts that require a flawless finish and parts that will be painted and polished.
9. Automate post-processing activities
While FFF parts need sanding, SLA and LFS printed parts require washing and curing with UV light to transform them into strong, stable, and long-lasting parts.
If you choose the Formlabs ecosystem, you can purchase the Form Wash L and Form Cure L, two post-processing units that take care of washing and curing to automate post-processing activities and free up your time.
The Form Wash L is an automated wash station designed to accommodate printed parts with LFS and SLA. The tank is a millimetre perfect fit for the Form 3L build plate, so you can insert your models attached to the build plate. Or, if you prefer, you can remove them. You fill it with Isopropyl Alcohol (IPA).
The Form Cure L is a UV post-curing station with an adjustable heat chamber. Models bathe in a 405 nm UV light source courtesy of multi-directional UV LEDs, and there are two 500W heaters. The Form Cure also has a rotating turntable for constant UV exposure and pre-programmed settings for all Formlabs resins.
10. Snap away support structures (with LFS)
Low Force Stereolithography solves SLA’s challenge of high peel forces with a flexible resin tank and linear illumination to reduce print forces.
The Form 3L produces parts that let you pull away at the support structure, and it snaps off cleanly. Compare this to SLA – where support structure can damage parts, leaving behind traces of plastic – and you can see the benefits.
The issue of high peel forces in SLA is that peel forces introduce limitations around materials and parts that require sturdy support structures to print successfully. These structures are hard to remove from printed parts without damaging them.
Snapping away support structure and leaving behind no mess never gets old, especially when you are printing intricate parts with that large build volume. LFS significantly reduces the post-processing challenges of large format SLA.
Summing up
Large format SLA is the perfect tool for producing large, complex models and scaling up small series production. The ability to print one series in half the time of smaller printers unlocks incalculable efficiency improvements. Time is money, so it makes sense to use every square inch of desk space when possible.
Formlabs takes things further with Low Force Stereolithography with the Form 3L, which is faster than traditional SLA and much higher quality. You can print models that are more accurate than ever without adding to production time.
Find out more
You can call us on 01765 694 007, send us an email at team@additive-x.com or book a discovery call with our Formlabs specialists Elaine Rutledge or Tammy O’Neill.
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