DLS 3D printing uses light to harden liquid resin in layers and create parts. While this is a relatively new technology, it already has applications in many different industries, from footwear and automotive to dental. But how does it work and what exactly can you make using a DLS 3D printer? Let’s find out.
DLS is the acronym for Digital Light Synthesis. This, as the words imply, is a process where light is used to produce specific parts based on a digital or 3D computer model. A digital light is ideally produced by special optical devices consisting of microscopic mirrors specifically arranged to reflect and project light.
Digital light synthesis technology involves using these optical devices for manufacturing. This manufacturing process was originally developed around 2014 as a way of making parts on a 3D printer. Since then, the DLS has become one of the most innovative technologies for 3D printing.
DLS 3D Printing
As already mentioned, DLS 3D printing is the use of digital light synthesis to create parts on a 3D printer. The main component in this process is a photosensitive resin. This is a type of resin that can harden when exposed to UV light.
In order to understand how this works, let’s go through the parts that make a typical DLS 3D printer, the materials used, and more.
DLS 3D Printer
A DLS 3D printer is composed of these major parts: UV light engine or source, an oxygen permeable window (screen) and the build platform or plate.
- The light engine is where the light to trace the part outline originates. During the DSL 3D printing process, this light is projected onto a reservoir of liquid resin from beneath, through the oxygen window. The light will then harden just a thin layer of resin.
- The oxygen permeable window is a space between the part being printed and the light source. It allows small quantities of oxygen in and serves to create an area above its surface called a “dead zone.” In this area, the resin remains liquid while the resin above it hardens upon exposure to UV light.
- The build platform is the upper part of the DLS 3D printer that serves to hold the printed part until its manufacture is completed. It typically rises as the part is being 3D printed, thereby drawing the hardened section from the liquid resin.
Carbon DLS 3 D Printing
In the world of DLS 3D printing, you will usually find it being called carbon DLS 3D printing. This is because the process uses carbon materials to make products. Carbon offers several benefits, such exceptionally smooth part surfaces. It also provides parts with excellent mechanical properties through the entire structure. Here’s how it works:
- At the beginning of the DLS 3D printing process, the build platform or plate dips into the resin. The light source then projects the part’s outline through the oxygen, hardening just a thin layer above the “dead zone”.
- The build platform then slowly moves up to draw the hardened part from the liquid resin vat, progressively as the other layers of resin continue to harden.
- Once the printed is completed, the part is removed and cleaned to remove excess resin. The support structures are also removed.
- The cleaned part will the, if necessary, be taken to an oven where forced circulation is used to cure it for hardening. This can take from 4 hours to 13 hours.
- After the curing process, the part may be coated with a material of choice, although this is often not necessary.
Carbon DLS Materials
DLS 3D printing is a form of vat polymerization technique. That means it uses photosensitive materials to make parts or materials that react to light. Carbon DLS materials in use today include the following: rigid and flexible or elastomeric polyurethanes, epoxy, cyanite esters, and silicone.
- Some DLS materials can resist heat and chemicals or impact, while some are better at absorbing vibrations or resisting tears. Based on the properties of each, the best application is determined.
- Cyanite esters, for example, are best suited for parts that will be used in high temperature and corrosive conditions, as the material can stand up to heat and corrosive chemicals.
- Polyurethanes, available in both rigid and flexible versions, are among the most used materials for DLS 3D printing. They can resist impact, tearing and be flexible enough to absorb vibrations.
- Silicone, with its biocompatibility properties, is mostly used to produce wearables. It also resists tears and other conditions such as impact.
Carbon DLS Vs. SLA
Carbon DSL 3D printing uses a process that’s similar to SLA 3D printing called stereolithography. However, there exist a few subtle differences that make each 3D process unique and best suited for the making of different parts.
- First, unlike SLA, carbon 3D printing is a continuous process: the resin continually flows into the zone above the oxygen window, while the light source continually hardens the resin until the part is completely printed, without pausing.
- SLA, on the other hand, hardens the part being printed one layer at a time. This makes DLS 3D printing a faster method of printing parts. It also means parts with smoother surfaces and consistent mechanical properties all through.
- DLS 3D printing, based on the fact that it uses carbon materials, produces parts that are waterproof, among other benefits such as structure consistency. This is useful in many applications such as automotive and footwear.
Overall, DLS 3D printing has several advantages over SLA printing: it creates part with high mechanical strength and excellent finishes, which makes it suitable for any different applications, including the most demanding.
Being a continuous process, also, DLS printing is one of the fastest and accurate methods to 3D print objects. That being said, it has its downsides as well. One of them is that it remains a costly process, both in terms of materials and printer cost.
DLS 3D printing offers speed and accuracy when used to produce parts, whether prototypes or end user parts. That’s in addition to allowing for complex part designs. Today, its use cuts across several industries including automotive, medical, electronic, sports equipment, and more.