3D printing, also known as additive manufacturing technology, gains its momentum in most recent years. Based on digital model files, 3D printers are capable to use some cohesible materials like alloyed powder or non-metal stuff to construct a 3D model through layer-by-layer printing method. First, 3D printers will analyze the online digital model files while processing them into slice pieces, and then according to the systematic route the printing head will move while extruding fused filaments out of the nozzle, and the machine will start constructing. FDM (Fuse Deposition Modeling) and SLA (Stereolithography) are the two most common printing technologies in this marketplace.
For the beginners, FDM and SLA are the most appropriate method for them entering the 3D printing wonderland. And as for those professional personnel, FMD and SLA are also the most welcomed ones popping up in this ever-developing technology. Although the different technologies are able to print out the same models, components, or let’s say, the same finished products as we wish, the further details of the models out of different printing technologies still exist. Let’s just check out the differences between these two technologies.
FDM
The working principle of FDM is that the Filament will be extruded by the extruder onto the platform, and then starts the printing process through piling up the melted filaments layer-by-layer till the final model is shaped. Various filaments can be adopted using this technology, like ABS, PLA and other compounded materials mixed with multiple enhanced powder. So 3D printers adopting FDM possesses a super wide range in this market with a broad application.
Advantages of FDM:
Compared with SLA, FDM 3D printer owns a far more bigger constructing size, besides it can design and print some practical components and models, it can implement a mass production in a small scale. A single type of 3D printing material generally has low resistance, low friction, high strength and certain anti-corrosion properties, while composite materials generally refer to materials containing reinforced material powder or chopped fiber mixture in the main material, such as poly Carbonate and carbon fiber can be used to print stronger, lighter and dimensionally stable parts. FDM 3D printing ranges from model display, small replacement parts for automobiles to tooling fixtures for aerospace companies, making it a stronger choice for objects that require mechanical functions and performance. Some FDM 3D printers have high-precision printing characteristics, so that the surface of the printed parts is smooth and uniform, which can meet the general use test requirements.
Downsides of FDM:
Confined by its low resolution power, finished products or models made by the conventional 3D printers of FDM will sometimes come with some unavoidable lines on their surfaces. And these sorts of “flawed” models require some additional polishing process to remove the residues. Besides, temperature fluctuation is also the most common problem existing in FDM 3D printing process, which might cause a clumsy and slow-down action on cooling down the filament.
Promising Side of SLA:
Compared with FDM, the most promising factor that SLA prevails is that it can realize a 25 microns resolution power at its least, in result it makes the product smoother with a more delicate detail. In this sense, it can totally rival and compete with the traditional injection molding, while bearing a great resemblance with it on their finished products. This kind of application is quite suitable for producing some certain products for displaying, concept model producing, organic structures, components with more complex geometric configuration, other sculptures and unique gadgets and novelties. Adopting the UV light as its core aligning component, SLA 3D printers possess a minor error in printing proces.
Shortcomings of SLA:
Owing to the fact that cured resin materials feature brittleness, only some certain formulas of industrial SLA resin can be applied to bear the mechanical stress or the components of cyclic loading. Besides, most standard resins are quite suitable for producing any model products with fine structure and high surface smoothness. Speaking of solidity and mechanical properties, there still exists no SLA resin materials which can rival with polycarbonate, nylon and other solid FDM materials currently. In addition, when it comes to the prime cost, resin material will cost much more than other sorts of materials. Plus, compared with FDM 3D printers, SLA printers can only produce models of smaller size and can’t be applied to mass production.
