Few years back 3D printing or additive manufacturing was just suitable for prototyping but now it encompasses many forms of technologies and has metamorphosed almost every vital industry. The process of creating 3D solid objects from a digital file has become a prominent product development tool across jewellery, manufacturing, dentistry and much more.
Now that printers have improved, have become more affordable and easy to-use, it has increased the dilemma among the people to select the best 3D printer.
The most popular and commonly used variants specifically refined for the desktop are:
Ø Fused Deposition Modelling (FDM)
Ø Stereolithography (SLA).
Many factors are considered when considering FDM and SLA printers such as their build volume, cost, printing speed, design and much more. But before moving ahead with the 3D printer FDM vs SLA comparison, let’s begin with the basics.
Introduced in the year 1980, these innovative technologies have improvised with better material, resolution capabilities, speed and size. Though both are good at their own phase, let’s take a closer look at FDM and SLA Printers to help you choose the technique ideal for your needs.
WHAT IS FDM 3D PRINTER?
Invented and patented by Scott Crump, the Fused Deposition Modelling (FDM) uses a thermoplastic polymer in the form of filament to make 3-D objects.
It is also known as FFF (Fused Filament Fabrication), the term was coined by the members of the RepRap project. These printers build a platform by squeezing thermoplastic filament via heated nozzle. Filament such as Acrylonitrile Butadiene Styrene (ABS), Polylactic Acid (PLA) is heated first. Later when the material melts it lays down one layer over the other until the process is complete.
FDM 3D printing is quick at work and works well for basic proof-of-concept models and prototyping of simple parts at low cost.
WHAT IS SLA 3D PRINTER?
World’s first ever patented 3D printing technology, SLA (Stereolithography Apparatus) is still one of the most widely used technologies for professionals. These printers work according to the process of Vat Photopolymerization where SLA uses liquid resin material to print articles/objects.
Here the powerful laser is used to create a 3D object. The process where liquid resin cures (hardens) plastic by using a laser is called photopolymerization. In this technology, the vat is filled with liquid thermosetting resin and the laser source sits at the bottom of the vat selectively flashing onto the liquid photosensitive resin. This exposure to the laser hardens (cures) the material. The process continues until each and every layer is exposed to the laser and cures. Once this is completed, it moves from one layer to the other until the entire model is cured and the 3D print is ready.
SLA resin 3D printers are better known for their ability to create precise, isotropic and watertight prototypes and parts. Well-suited for highly detailed prototypes that require smooth surface and tight tolerance. From engineering and product design to dentistry, jewelry, education and manufacturing, Resin 3D printing forms a great option.
FUNCTIONALITY OF FDM and SLA 3D PRINTING
Both FDM and SLA 3D printing follow the same workflow i.e. designing, 3D printing and post processing. But how do they differ?
3D PRINTER FDM vs. SLA
When comparing the two 3D Printing Technologies, following factors should be considered:
1. MATERIALS AND COST
FDM 3D printing uses a range of standard thermoplastic filaments and their several blends. Other engineering materials such as Nylon, PA and other high-performance thermoplastics like PEEK are also available but are limited to a few FDM printers only that support them.
Cost: FDM can be considered as an inexpensive technology available. Not just the whole machine but the materials used in the operations are inexpensive too resulting in affordable products manufactured through FDM 3D printers.
The base thermoplastic materials are cheap, quite affordable and are easily available at comparable prices.
Making FDM printers an affordable choice for small business owners to try if 3D printing is worth it if added in their template.
SLA printers use a limited range of materials. As the technology uses photosensitive thermosetting plastics in a liquid resin form, these are quite expensive and are usually manufactured by the SLA printer manufacturers.
These distinguished materials are used for particular applications like dental, jewelry etc.
Cost: An expensive machine that uses expensive parts such as laser source and scanning mirrors resulting in expensive 3D printed output.
2. COLOR & BLENDS
The traction of FDM 3D printing has led to plenty of color options. During production, whichever type of material is used, dyes can be easily mixed with the material to create a full range of colors offering engineers flexibility.
On the other hand, SLA does not have a variety of color options. Infact, usually they are available in black, gray and transparent colors. As the SLA materials are the blended form of the primary base material, they are usable as the application-based materials
3. PART STRENGTH
When it comes to producing durable and long-lasting parts, FDM printers tend to have an upper hand. These printers are capable of printing in known polymers and composites.
SLA printers comprise cured resins which tend to be fragile. Hence, they are more into the creation of intricate and detailed parts instead of strong ones. Unlike FDM prints, SLA prints would result in print failure and cracking when printed solid.
4. PRINT QUALITY & PRECISION
The process of layer formation during the manufacturing process largely affects the surface quality and the level of accuracy, accordingly changing the overall print quality.
Here the layers are formed by settling lines of molten material. Depending on the size of the nozzle, voids stay in between the rounded lines. Due to which layers do not stick to one another leading to inability to create complex details.
Well known for its outstanding features, smooth surface finish and accuracy these printers use a highly precise laser that cures the liquid resin to form each layer. Further creating much finer details and achieving high-quality results frequently.
5. EASE OF USE
Hassle free process is what FDM printers can be considered for.
FDM printers are relatively easy and simple to use. All that should be done is insert plastic filament at one end and extruder at the other. Even when the printing process is over, parts come out dry which does not require cleaning.
To facilitate 3D printing, both FDM and SLA processes use support structures.
Further, the remaining material gets stored in hard plastic material for the next print. Unsupported finished parts are ready for the process whereas supports on the FDM parts should be removed manually or dipped in water (depending on the support material).
However, supported FDM prints where high-quality finish is the prerequisite inculcates lengthy manual post-processing.
Though, SLA printing parts look good but need extra efforts. This is a chemical-loaded process due to which these are usually found in closed labs.
Once the printing process is over, the parts come out sticky. Hence, you need to remove the parts from the building platform first and later manually dip those in the solvent to get rid of the excess resin.
Note: Resin can be highly toxic, do wear gloves, goggles and other protective equipment for protection.
The supports on the SLA parts require clippers to clip those off. Later, a few SLA materials may require post-curing to achieve highest stability. Hence, a UV lamp is used to finish the part.
Whether you choose FDM or SLA, if you want to keep your machine working smoothly and decrease the likelihood of unexpected failure, invest time in your 3D printer maintenance service.
Both FDM printers and SLA printers have proven records across various industries. It’s up to the requirement of the designer or an engineer whether they need the strong part printed in regular materials or want to have highly detailed designing that is appealing.
If you want a sturdy and usable part like a FDM printer or an attractive, detailed option like the SLA printer – the choice stays yours. Either way, you’ll get the benefit of achieving quick digital design.
Conclusively, do not forget about regular 3D printer maintenance service for a smooth-running experience with your printers!