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Thinking About Purchasing an SLA Printer? Here’s What You Need to Know:

Thinking About Purchasing an SLA Printer? Here’s What You Need to Know:

Perhaps you’ve watched the mesmerizing videos of SLA printers pulling out perfect trays of shiny prints, or you’re becoming familiar with the technological variety of opportunities available to these types of printers. Either way, you’re now stuck with the question: how do they work? 

Stereolithography uses “photo-solidification”, which involves the hardening of liquid monomers and oligomers into polymers using some type of light source. A common type of SLA printing uses UV light and photosensitive resins, where the resin is exposed to UV light layer by layer as directed by uploaded CAD-made design files. Inverted-SLA printers have been more common recently, print by creating a thin layer of resin between the build-plate and the source of UV light, and as the print progresses, inching the build-plate up to create each layer. 


Specifications/Abilities: 


Of the variety of methods placed into the category of 3D printing, SLA printing has a significantly higher resolution and capacity to create intricate, highly complex parts and surface structures. Because SLA uses a laser to solidify parts, the only constraint of the resolution size is the size of the laser. This typically ranges between 30-140 microns. 

SLA printed pieces have uniquely smooth and watertight finishes, which are created by what has been called the isotropic effect of SLA printing. Isotropic materials have the same properties in every direction, which is incredibly useful for 3D printing that functions on x,y, and z planes. SLA prints have this property due to the uniformity of the surfaces when hardened as well as the chemical reactions between the layers as they are built, which continue to polymerize as the print is created, cross-linking the layers with covalent bonds. 


Cost:

With extremely high quality precision printing, the price tag tends to match. SLA 3D printers tend to be more cost demanding upfront due to the high price of the printers themselves. Additionally, the resins used for this type of printing tend to cost twice as much per unit as typical FDM plastic filament spools. However, there is promising development in accessibility to SLA manufacturing, which was once only available for large industrial uses when it was first developed but can now be operated tabletop. 

Project 3D Printers has some of the cheapest new SLA printer models listed for prices as low as $540 for the Anet N4 3D Printer, as well as higher end models such as the UNIZ Slash DJ2 3D Printer.

Perhaps you’ve watched the mesmerizing videos of SLA printers pulling out perfect trays of shiny prints, or you’re becoming familiar with the technological variety of opportunities available to these types of printers. Either way, you’re now stuck with the question: how do they work? 

Stereolithography uses “photo-solidification”, which involves the hardening of liquid monomers and oligomers into polymers using some type of light source. A common type of SLA printing uses UV light and photosensitive resins, where the resin is exposed to UV light layer by layer as directed by uploaded CAD-made design files. Inverted-SLA printers have been more common recently, print by creating a thin layer of resin between the build-plate and the source of UV light, and as the print progresses, inching the build-plate up to create each layer. 

 

Specifications/Abilities: 

 

Of the variety of methods placed into the category of 3D printing, SLA printing has a significantly higher resolution and capacity to create intricate, highly complex parts and surface structures. Because SLA uses a laser to solidify parts, the only constraint of the resolution size is the size of the laser. This typically ranges between 30-140 microns. 

SLA printed pieces have uniquely smooth and watertight finishes, which are created by what has been called the isotropic effect of SLA printing. Isotropic materials have the same properties in every direction, which is incredibly useful for 3D printing that functions on x,y, and z planes. SLA prints have this property due to the uniformity of the surfaces when hardened as well as the chemical reactions between the layers as they are built, which continue to polymerize as the print is created, cross-linking the layers with covalent bonds. 

 

Cost:

With extremely high quality precision printing, the price tag tends to match. SLA 3D printers tend to be more cost demanding upfront due to the high price of the printers themselves. Additionally, the resins used for this type of printing tend to cost twice as much per unit as typical FDM plastic filament spools. However, there is promising development in accessibility to SLA manufacturing, which was once only available for large industrial uses when it was first developed but can now be operated tabletop. 

Project 3D Printers has some of the cheapest new SLA printer models listed for prices as low as $540 for the Anet N4 3D Printer, as well as higher end models such as the UNIZ Slash DJ2 3D Printer.

Jewelry: SLA printing can be used for custom jewelry making, allowing designers to generate complicated surface designs using CAD that can then be used to create molds for different materials such as gold and silver. Additionally, fast prototyping using SLA can speed up the fitting process when creating custom jewelry.

Manufacturing: SLA prints have been used to create molds, custom prototypes, complex parts, and consolidated structures that help to speed up the ultimate build time of larger projects.

Film/Entertainment: SLA printers can be used to create some of the more complex props and pieces used in entertainment in a way saves time and prevents limitations in design.

Software:

SLA printers are compatible with the same CAD softwares that are used for FDM printing, and 3D model files can be exported as STL or OBJ files and fed directly to the printer (you can use the same files for an FDM printer and an SLA printer). SLA printers have specific software as well that is used to calibrate and adjust printing settings, which are used to break up the 3D OBJ or STL file into layers. However, while it may be easiest to use the same files from your FDM printer with your SLA printer, designing specifically for SLA has its advantages as it can save material and generate appropriate supports. 

Materials Used:

The variety of materials that can be used for SLA printed is unlimited when it comes to material properties. Depending on the type of effect desired, there is a large developing market for different types of resins. Dental resins are developed for use in the medical field or inside the mouth, while ceramic resins have material properties that create a hardened, ceramic finish. Variables such as high temperatures, durability, corrosion resistance and yield strength are all up for grabs. 

Finishing Prints:

 

Unlike FDM prints, SLA prints are submerged in resin and require some post processing, which typically involves an isopropyl alcohol rinse followed by a period of time for curing. Similarly to FDM, rough surfaces generated from support structures can be easily cleaned by sanding. 

SLA printers are make up the high end of 3D printing for quality and product in businesses. While they are an investment, they have an immense payback in quality and ability, as well as consistent repeatability. Stay tuned for future posts about troubleshooting typical SLA printing problems and deciding what level printer is right for you!

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