3D printing is a manufacturing technology that was invented in the 1980s. It has since evolved from being a rapid prototyping tool to full-fledged manufacturing technology. The evolution has been revolutionary leading to its adoption in a variety of sectors from automotive to aerospace, from healthcare to sports and from defense to fashion. The industrial term for 3D printing is additive manufacturing since the material is continuously added to manufacture an object (as opposed to subtractive processes like cutting, milling, and machining). We introduce you to this rapidly growing revolutionary manufacturing technology.
In this section, we will share the answer to the question: “what is 3D printing?” As mentioned, 3D printing is a manufacturing technology that converts a CAD design into a three-dimensional solid object by successively laying down thin layers of materials one on top of another. In simple terms, it converts a virtual design into a physical object.
But 3D printing is not a single technology. It has several technologies that operate on the principle of additive manufacturing.
The 3D printing workflow includes a series of steps that are essential to manufacturing an object. Below is the 3D printing workflow:
CAD Model: This is the first step towards 3D printing. It is the most vital element for 3D printing without which an object cannot be manufactured. A CAD model is created in a 3D modeling software (like Solidworks, Onshape, Rhino, etc.). Alternatively, a CAD model can also be obtained through reverse engineering by using a 3D scanner or through an online resource such as Thingiverse or GrabCAD. This CAD model is required to be compatible with 3D printing design rules to be able to be used for 3D printing.
Slicing Software: This is the second step in the 3D printing process and involves converting the CAD (or more often an STL file) into a file the 3D printer can read. The CAD model is imported into slicing software. The slicing software controls a range of parameters that can result in better 3D printing output. In most “slicers” you’ll find a visual representation of how the print will appear on the build plate so that you can properly orient it for best results. Some of the parameters that can be controlled are layer height, speed, temperature, raft layer adhesion, etc.
Original slicers were basic, but today slicers such as MakerBot CloudPrint are cloud-based and allow for not just print prep, but also remote monitoring of print process, job queuing, and reporting.
3D Print: This is the final step to complete the 3D printing process. The sliced file from the slicer software is sent to the 3D printer. Now with just the press of a button, the 3D printer will start printing the object in a layer by layer form until the object is complete and ready for retrieval or “harvesting”.
The ASTM classifies all 3D printing technologies into seven categories namely material extrusion, vat photopolymerization, powder bed fusion, material jetting, binder jetting, directed energy deposition & sheet lamination. As we continue down the road of “what is 3D printing” here are some of the most popular technologies:
Fused Deposition Modeling (FDM) or Fused filament fabrication (FFF)
This is a material extrusion type of 3D printing technology. MakerBot is one of the leading manufacturers of FDM 3D printers and filaments. FDM 3D printers use thermoplastic polymer material in a filament form that is heated and deposited onto a build platform in a layer by layer form to form the complete object.
Stereolithography (SLA) & Digital light processing (DLP)
Stereolithography (SLA) was the first-ever patented 3D printing technology to be developed and commercialized. It falls under the vat photopolymerization category of 3D printing technology. It uses a photosensitive liquid resin material that is cured by a laser. The laser cures the resin point by point in a continuous process to ultimately form the entire object. Digital light processing (DLP) is a similar technology that uses projected UV light in place of a laser which can result in faster printing.
Selective Laser Sintering (SLS)
Selective Laser Sintering (SLS) is a powder bed fusion 3D printing technology that uses powdered polymer materials to form solid objects. This technology also uses a laser to sinter or melt the powder particles and fuse them to form the entire object.
Other technologies like Direct Metal Laser Sintering (DMLS), Selective Laser Melting (SLM), and Electronic Beam Melting (EBM) operate on a similar principle of powdered materials being fused with lasers (electron beam instead of a laser in case of EBM).
To understand the question of what is 3D printing, one must understand the materials that can be used in 3D printing. MakerBot manufactures a wide range of FDM materials catering to all sorts of applications right from basic concept prototyping polymers like PLA to manufacturing-grade composite materials like carbon fiber. Let us take a look at some of these materials:
Polylactic acid (PLA): PLA is the most common FDM material. It is a biodegradable polymer material made from corn starch. PLA is a great material for early concept models because it is easy to use, office-friendly, and works great with breakaway supports which print faster and can be removed faster than dissolvable supports.
Acrylonitrile Butadiene Styrene (ABS): ABS is one of the most popular materials for injection-molded consumer products due to its clean surface finish, durability, and heat resistance. METHOD X can print manufacturing-grade ABS without warping and without weakening additives thanks to its 100°C heated chamber.
Nylon: Nylon is an excellent material for replacement parts in a manufacturing facility due to its high degree of abrasion resistance. It also has a relatively high impact strength and heat resistance further adding to its popularity with professionals. One drawback of Nylon is it may absorb moisture readily from the air which can lead to difficulty with both the filament and the printed part.
Nylon 6 Carbon Fiber: Nylon 6 Carbon Fiber has the strength and lightweight benefits of other carbon fiber composites. The main thing about Nylon 6 that sets it apart from others in that category is its ability to withstand higher temperatures. The heat deflection temperature is significantly higher than many of the popular base polymers. In the case of MakerBot Nylon Carbon Fiber, the HDT is 100°C higher than that of ABS and 93°C higher than regular Nylon 6.
Nylon 12 Carbon Fiber: Much like Nylon 6 Carbon Fiber, the Nylon 12 variant has the benefits of strength, stiffness, and lightweight. Unlike Nylon 6, Nylon 12 has a better resistance to moisture uptake, making it somewhat easier to print and giving the printed part a cleaner final appearance without the need for post-processing. One drawback of Nylon 12 compared to Nylon 6 is it will generally have a lower HDT - so you really just need to weight what is most important for your specific application.
Polyvinyl alcohol (PVA): PVA is a water-soluble support material that is compatible with many lower temperature model materials such as PLA and PETG. Because PVA is water-soluble it is very office-friendly and is a great option for printing the most complex geometries in a prototyping environment.
SR-30: SR-30 is a proprietary material developed by Stratasys to work seamlessly with ABS, ASA, and various other high-temp materials. Because of this focused development, using SR-30 with these typically more challenging materials can yield exceptional results that wouldn’t be possible with something like PVA, which is very difficult to use with ABS.
3D printing has developed into a powerhouse technology that has applications in wide-ranging fields. We see some of the popular applications as we continue to answer the question ``what is 3D printing?”
The ideal approach to new product development is through the design thinking principle but that cannot be applied as our current manufacturing methods do not allow us to iterate multiple ideas economically. It becomes difficult to spend huge amounts of money on the iteration phase. But 3D printing helps in rapidly and affordably iterate multiple product ideas. This helps in building a better customer-centric product.
In-house Manufacturing Aids
3D printing is the ideal technology to create customized manufacturing aids to improve in-house efficiencies in production and assembly stages. Customized aids like jigs & fixtures, guides, test gauges, maintenance tools, fit for purpose tools, etc., can be rapidly developed.
Companies always have to be on their toes and the latest trend in manufacturing is on-demand manufacturing. 3D printing has significantly boosted this new approach to manufacturing. This not only delivers the product to the customer on time but also reduces the load on its warehouses and the associated investment in inventory.
Digital manufacturing is an extension of on-demand manufacturing wherein products can be manufactured right on-demand but through a website. The customer has to upload his CAD file and the 3D printer can use that file to rapidly 3D print the object as per the customer requirements.
Want to find out which is going to be the best fit for you and your organization? Talk to a MakerBot 3D printing expert today!