Resin 3D Printers

3D printing with resin 3D printers creates objects by altering the chemical structure of a photopolymer resin liquid. This 3D printing technology allows the liquid to harden and turn into a solid structure. Similar to FDM 3D printers (Fused Deposition Modelling), the objects printed with resin 3D printers are constructed one layer at a time.

However, 3D models printed with a resin 3D printer do not have the distinctly visible layers that are usually present in objects printed with the filament used by FMD printers. Resin 3D printers create objects with smooth finishes and can accommodate highly intricate details in designs.

What is a resin 3d printer?

Resin 3D printers make use of a resin to produce 3D models or objects. The resin is a photopolymer that is held in a resin tank. When the photosensitive resin is exposed to light, it is activated (or cured) and becomes solid.

How does a resin 3D printer work?

Resin 3D printers work by building the object from the base up. Some resin 3D printers make use of a suspended platform. The object sits on the platform, and each layer is created on top of the one before by light that is pointed down into the tank. Once each layer is completed, the platform moves down incrementally. The liquid resin fills the space above the platform and gets cured by the light.

When the object is suspended from the building platform, it is built upside down. It is then attached to a building platform with supports. The building platform moves up after each layer has been completed to allow the liquid resin to fill the space between the previous layer and the bottom of the resin tank. Each new layer is added to the bottom of the object by a light sent up through the tank. This is the most popular method of 3D printing.

Different Types of Resin 3D Printers

There are different kinds of resin 3D printers: Laser Stereolithography (laser SLA), Digital Light Processing (DLP), and printers that use a Liquid Crystal Display screen to mask projected light (LCD-based).

Laser Stereolithography (SLA) makes use of UV lasers to cure the resin in the tank. In Laser Stereolithography 3D printing, a laser cures the resin spot by spot to create the object. SLA 3D printers can produce a print of any size and resolution. Because SLA 3D printers build up an object point by point, they can produce precise and extremely detailed objects. Prices for SLA 3D printers start at around $1,000, with industrial-scale models reaching several hundred thousand dollars.

Digital Light Processing (DLP) resin 3D printers cures the resin by using a light projector. The light is projected in a specific shape to print the object one entire layer at a time. The light is essentially projected in the shape required to print each specific layer. The shape of the light is manipulated by using a complex system of mirrors to reflect the exact shape needed for each layer.

Because a DLP 3D resin printer exposes and prints entire layers at once, it could potentially generate a specific image faster than an SLA 3D resin printer. The projectors are also easier and cheaper to change than the lasers used in SLA 3D resin printers.

On the other hand, a DLP 3D resin printer’s resolution depends on the projector and how many voxels or pixels the projector has. Most full HD projectors have 1080p. Because the projector has a fixed number of pixels, objects created with DLP 3D resin printers aren’t always able to print small details when building at full scale. DLP 3D printer prices start around $2,000 and go up from there depending on the features and level of precision.

Liquid Crystal Display (LCD) resin 3D printing is also sometimes called Masked SLA or MSLA. In this type of resin 3D printing, an array (or group) of LED lights shine through an LCD screen into the resin tank. The LCD works as a stencil or a mask that only allows a specific shape of light through. Similar to DLP, the object then gets printed one layer at a time. The shape of the light that shines through the LCD screen changes as the 3D printing progresses to accommodate changes in the shape of the object being printed.

The use of LCD screens has made this type of resin 3D printer more affordable and widely available. Many LCD 3D printers are available for under $1,000.

Steps Involved in Resin 3D Printing

3D printing is sometimes also referred to as additive manufacturing. It is the process of taking data created by specialized software, providing it to hardware (the 3D printer), and creating specific objects one layer at a time.

Design.

The first step to printing a 3D model is the design. Designs can be created on Computer-Aided Design (CAD) software or by making use of 3D scan data. The information is then exported in a 3D printable file format (like STL or OBJ). This is then inserted into the resin 3D printer. 3D resin printers have software that analyzes the data and creates print settings to create the 3D object one layer at a time. These printing instructions are then sent to the 3D printer.

Select your printing material.

Resin-based 3D printers can print objects from various 3D printer resin materials. 3D printing resin materials are different from the filament used by a filament printer. Standard resin is the most budget-friendly option. It is smooth and translucent while printing objects with a high level of detail. Mammoth resin can be used to print larger (mammoth) pieces. Transparent resin is ideal for smaller pieces that need to have a smooth surface and are transparent. Engineering resins produce objects that are strong while lightweight.

Print.

Once the print instructions have been checked and confirmed, the resin 3D printer will begin the printing process. The printer can be left unattended until the print is completed. In some cases, the printer will need to be manually refilled with resin. In contrast, others make use of a cartridge system that does this automatically.

Resin removal.

The cured objects printed with a resin 3D printer will be covered in a layer of uncured resin that needs to be removed. Uncured resin can be removed by dipping the object into isopropyl alcohol (IPA). You can then gently scrub away the layer of uncured resin.

If you plan on 3D printing large amounts of objects, you could invest in a resin washer or resin cleaner. These machines cut down the manual cleaning that you will need to do after removing each object from the resin tank. Remember that your resin 3D printer’s platform will also need to be cleaned.

Post-curing.

Some 3D models printed with a resin 3D printer could still be slightly soft and malleable. The object will need to undergo a post-curing process to obtain its highest possible strength and stability. This is done by exposing the object to either heat or light. In most cases, UV light is used. Most resin 3D printer manufacturers also produce dedicated UV curing chambers, which can be used for post-curing. You could also use a UV nail lamp (for smaller objects) or build your own UV curing chamber.

Post-processing gives strength to 3D printed objects. This is essential for parts used in engineering, and in many cases, mandatory for parts used in dentistry and jewelry making.

Removing the supports.

The final thing to do is remove any supports from the object. These areas will then need to be sanded down to give the object a clean finish.

The Benefits and Limitations of Resin 3D Printers

3D printing with resin allows you to build small objects with a lot of fine and complex details. A variety of materials can be used, including colored or transparent resin, ceramic, and metal. The objects printed with resin 3D printers have smooth finishes – unlike the visible layers produced by the filament used by FDM 3D printers (Fused Deposition Modelling printers).

However, objects printed with resin 3D printers require post-processing. Both the model and the printer (including the resin tank) need to be cleaned after the printing is complete. Resin printing requires specific safety precautions when handling the material to avoid inhaling toxic fumes that the 3D printing process could produce.

When looking for a 3D resin printer, you need to consider the build volume. The build volume of a 3D printer is the maximum size that you can print any specific object. If you need to print objects larger than your printer’s build volume, you may need to print several parts that can be assembled afterward.

Resin 3D printers let you print objects from resin. They are ideal for objects that have intricate details. The finished product requires some processing after it is printed to remove uncured resin and remove any supports, but in the end, you will have a 3D model that is detailed with a highly smooth finish.