Filament vs Resin 3D Printer – Difference Between FDM and SLA 3D Printing | CNCLATHING


There are two primary techniques used in 3D printing services: Fused Deposition Modelling (FDM) and Stereolithography Apparatus (SLA), respectively utilizes filaments and resins to build the 3D models. Filament 3D printer vs resin, which one to choose? In this post, we are going to focus on the difference between FDM and SLA 3D Printing, so that you can determine it rightly.

What is Filament 3D Printer?

The filament-based 3D printer, also known as the FDM 3D printer, typically works with plastic filament, which is the thermoplastic feedstock for the technique called Fused Deposition Modeling (FDM) or Fused Filament Fabrication (FFF). In an FDM printer, a long plastic filament is fed from a spool to a nozzle where the material is liquefied and drawn, then hardens immediately. The nozzle moves to place the material in the right position to build the model layer by layer.

What is Resin 3D Printer?

SLA is an additive manufacturing technique like FDM, what differs is the material. The resin-based 3D printer or SLA (Stereolithography Apparatus) printer uses resin. A resin 3D printer applies a UV light to harden a liquid resin or curable photopolymer, the machine builds the object layer by layer from top to bottom, with the platform lifting out of its resin bath. The powerful and precise laser in SLA 3D printing makes the tiniest of movement count, allowing for a high print resolution and overall quality.

Filament vs Resin 3D Printer - Difference Between FDM and SLA 3D Printing (FDM vs SLA)

FDM and SLA printers are both common types of machines used in 3D printing, when you want to choose one between them, you should consider the factor with top priority, including cost, quality and more. Here we compare FDM and SLA 3D printing in different aspects, to help you find the more appropriate option fast when FDM vs SLA. 

1. Material. FDM 3D printing usually uses plastic filament such as PLA, ABS and PETG, most FDM printers can also work with nylon, PVA, and PLA blends. 3D printer filaments are available in a wide range of colors. SLA 3D printing uses curable photopolymer or resin materials, these are proprietary and cannot be exchanged between printers from different manufacturers, there are also more limitations on the color options. 

2. Principle: SLA printer irradiates the resin material by laser to make the photosensitive resin solidify at the irradiating spot, while FDM heats the material by the nozzle to make the melted material contact the printing platform at the nozzle and cool down.

3. Speed: Although both SLA and FDM printing makes three-dimensional objects from lines and surfaces, the laser movement speed of SLA in the plane is faster than that of FDM to the nozzle, so the forming speed of the SLA printer is much faster than that of FDM.

4. Cost: Various types of FDM printers have different prices, but they are generally cheaper than resin 3D printers, the structure is relatively simple, and the consumables are also cheap. The SLA is generally more expensive, relatively cheap printers use the LCD screen as a light source, which leads to low life, and the screen will burn soon. 

5. Precision: In FDM 3D printers, the precision and smoothness of the printed parts will be affected by many factors, such as the nozzle size, extruder precision and bonding force between layers. While SLA 3D printers can consistently produce models with a higher resolution. In resin 3D printing, the resolution is primarily determined by the size of the optical spot, both the laser and projector pixels are very small, the part surface is smoother in SLA printing. The minimum layer height is also much smaller for SLA printers than FDM, contributing to better quality and detail.

6. Adhesion: the work after printing is also important, such as maintenance and cleaning. In FDM printing, the 3D printed parts can be relatively easily removed, while with SLA printers, it’s difficult to remove the model from the print platform, there are often lots of resin remains on the platform and you have to clean and remove it. 

7. Strength: Due to the inherent properties of filament, FDM offers stronger parts than ordinary SLA 3D parts, strong filaments like Polycarbonate makes the FDM is a preferred choice, while resin prints are fragile. 

8. Applicability: In resin 3D printing, you need to wash the resin off by immersing the part in isopropyl alcohol, filament print is more manageable and does not need further processing. 


In a word, choose the printer based on your most urgent needs. For example, when the precision and smooth surface finish is critical to you while cost does not matter much, you should use an SLA 3D printer, while if you want to build low-cost models or require solutions for rapid prototyping, an FDM printer can be considered, it is also a better choice for hobbyists. Both resin and filament printers pose health and safety risks. So use both types of 3D printers in well-ventilated spaces.