In this week’s article we will continue with our discussion about 3D manufacturing, which is the process of contrasting a three dimensional object from a CAD (computer aided design) model. Last week, I introduced you all to 3D printing, talked about its origin and some historical facts and explained one of the most popular type of additive manufacturing, FDM (Fused deposition modelling). In this week’s article we will enrich our understanding and knowledge on 3D printing by introducing the rest of its types and maybe suggesting some reliable 3D machines you can all buy and start experimenting by yourself.

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Other types of 3d printing:

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2) SLA (Stereolithography) is a form of 3D printing technology used for creating models, prototypes, patterns, and production parts in a layer by layer fashion using photochemical processes by which light causes chemical monomers(a molecule that can react together with other monomer molecules to form a larger polymer chain) and oligomers (a molecule that consists of a few similar or identical repeating units which could be derived, actually or conceptually, from copies of a smaller molecule) to cross-link(bond that links one polymer chain to another) together to form polymers, a substance or material consisting of very large molecules, or macromolecules, composed of many repeating subunits. In other words, Stereolithography works by focusing an ultraviolet (UV) laser on to a vat of photopolymer resin. With the help of CAD software, the UV laser is used to draw a pre-programmed design or shape on to the surface of the photopolymer vat.

 

SLA printers were actually the first ever 3D printers to enter the market (in the late 1980s). The world's first 3D printing company, 3D Systems, commercialized it. Chuck Hull patented stereolithography as a method of creating 3D objects by successively "printing" thin layers of an object using a medium curable by ultraviolet light, starting upside down, from the bottom layer to the top layer.

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3) Selective Laser Sintering (SLS) is an Additive Manufacturing process that belongs to the Powder Bed Fusion family. In SLS, a laser selectively sinters the particles of a polymer powder, fusing them together and building a part layer-by-layer. The materials used in SLS are thermoplastic polymers that come in a granular form.

SLS 3D Printing is used for both prototyping of functional polymer components (typically nylon or polyamide) and for small production runs, as it offers a very high design freedom, high accuracy and produces parts with good and consistent mechanical properties, unlike FDM or SLA.

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How does the SLS fabrication process work:

I. The powder bin and the build area are first heated just below the melting temperature of the polymer and a recoating blade spreads a thin layer of powder over the build platform.

II. A CO2 laser then scans the contour of the next layer and selectively sinters (fuses together) the particles of the polymer powder. The entire cross section of the component is scanned, so the part is built solid.

III. When the layer is complete, the build platform moves downwards and the blade re-coats the surface. The process then repeats until the whole part is complete.

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2)Creality Ender 3 V2 (award for the Best FDM 3D printers under $300)

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Currently one of the world’s most popular 3D printers, the Ender 3 V2 costs under $300 yet brings sturdy reliableness and good quality 3D printing.

It’s a 3D printer kit, but it takes less than 45 mins to assemble and even most beginners will find the building process simple enough.

The Ender 3 V2 works great for printing the odd useful piece and any standard projects.

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What’s Great

• High-quality prints

• Excellent price-to-performance

• 32-bit board with TMC2208 drivers (read: it’s quiet)

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