3d Printing - 101

Introduction 

A 3d printer is an additive manufacturing technique where 3D objects and parts  are made by the addition of multiple layers of material. It can also be called as  rapid prototyping. It is a mechanized method where 3D objects are quickly made  as per the required size machine connected to a computer containing blueprints  of any object.  

The additive method may differ with the subtractive process, where the material  is removed from a block by sculpting or drilling. The main reason to use 3d printer  is for 90% of material utilization, increase product life, lighter and stronger. 3D  printing is efficiently utilized in various fields such as aerospace, automobile,  medical, construction and in manufacturing of many household products. 

History 

The 3D printing innovation is not a new concept as many think. When FDM (fused  deposition modeling) licenses had expired in 2009, the 3D printing became a new  innovation topic. What's more, because of which it turned out to be more  

mainstream, individuals envisioned that FDM was the just a single added  substance producing system. Be that as it may, the initial 3D printing procedure  was SLA not FDM, and its first patent was recorded in 1980's. Here is the historical  backdrop of 3D printing innovation, from 1980 to today.  

In 1980's there was the introduction of 3 primary 3D printing systems. Dr. Kodana  was the first person to present layer by layer approach for assembling and  furthermore he was the principal individual to create fast prototyping strategy.  What's more, he made a progenitor for SLA. He polymerized a photosensitive gum  with the assistance of UV light, however, did not succeed. Shockingly for Dr.  Kodana, the full patent detail was not recorded by him before the one-year due  date after the application. the causes of 3d printing innovation can be followed  from 1983.  

In 1983 Charles hull was the person to do a patent on stereolithography. Frame  designed the term stereolithography in august 8, 1984 patent application for  "Contraption for creation of 3 dimensional questions by stereolithography".  Furthermore, was the main individual to make SLA-1 (stereolithography) machine  in 1987.

Charles hull was the founder 3D system Corporation (one of the biggest and more  propel association working in 3d printer division today). Hull characterized  stereolithography as the unique technique which is used for making solid objects  by printing successive layers of ultraviolet curable material on top of other. In  frame's patent, he clarifies, a concentrated light emission light is centered around  the surface loaded with a fluid photopolymer. The light ray which is controlled by  a computer draws each layer of the model on the surface of the liquid. wherever  the bright light strikes the surface, the photopolymer polymerizes and changes to  solid. Using the software CAD/CAM mathematically slices (converts into layers) the  models. then the process builds the models layer by layer. 

During the year 1999 3D printing sector had started to begin the demonstrate  distinct diversification with these two very specific regions emphasis that is clearly  defined today. They were very high end 3D printing and still they are very  expensive which were geared up towards the par production for high value and  complex parts. This are growing rapidly and ongoing but the results are now visible  in production applications across the automotive, aerospace, medical and in  jewelry sectors. 

At the lower end of market, the 3D printers that today are been seen. During this  term there, price was a war between the 3D printing companies with the increase  in improvement, accuracy, speed and materials. In 2007 the market saw the first  system under 10,000$ from 3D systems but it never hit the market as supposed to  be. This was due to the market influence of other companies. 

All through in 2000 3D printing technology kept on developing to make lower priced models with multiple features. In 2009, was the year where the FDM patents  fell into the public domain, giving an expansive wave for the development in FDM  printers and due to the drop of the price of desktop 3D printers, the technology  was more accessible and increased visibility. A French company named Sculpteo  was started in this year which had offered 3D printing cloud and online printing  services using stereo lithography or laser sintering. which was another step towards  3D printing. 

As the various additive processes developed. It is said that soon metal removal will  no longer be the only metal removal process done through a moving head  through a 3D work envelope converting the mass of raw material into desired  shape layer by layer. In 2010 there was a first decade in which metal end use parts  like engine brackets and large nuts would be made by printing instead of  machining.

Principle 

i.Modelling: The object or the model which has to be printed first it has to  designed or modeled using a CAD (computer aided drawing) tool like solid works  etc. By the 3D scanner or by the digital camera and a very unique  photogrammetry software. These 3D printed models were created with help of the  CAD results in the reduction of errors which were found and can be corrected  before printing. In manual modelling process of preparing geometric data for 3d  computer graphics is similar to plastic arts such as sculpting. Based on this data 3- dimentional models of the scanned object can be produced. 

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After modelling in CAD tool the model often be (in .skp, .dae, .3ds or some other  format) then it needs to be converted to either a .STL or .OBJ format, to allow the  printing software to be able to read it. 

ii.Printing 

After the model has been converted to STL, it must be first examined for “errors”,  this step is called the “fixup”. In most of the cad applications produce errors in  output STL files errors like sekf intersection, improper holes, face normal has to be  corrected. 

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Once the file is converted to STL, the file has to be processed by a software called  “slicer” which will convert the model into series of layers and produces a G-code  file containing instructions to a specific type of 3D printer. This G-code file can be  printed by using 3D client software (which loads the G-code and uses it to instruct  the 3D printer during printing. In practice the client software and the slicer program  exist, including Cura, Slic3r, repetier host, pronterface and skeinforge as well as  closed source programs like simplify 3D and KISSIicer3D. 3D printer follows the G 

code instructions to lay down successive layers of liquid, powder, paper or sheet  material to build model from a series of cross sections. The such as plastic, sand,  metal etc can be \used through a print nozzle. These layers, which correspond to  the virtual cross sections from the CAD model, are joined or automatically fused  to create the final shape. Depending on what the printer is making, the process  could take up to minutes or hours. Printer resolution describes the layer thickness  and X-Y resolution dots per inch (dpi) or micrometers(μm).The layer thickness  which can be found can be around the 100gm mark, although some of these  machines such as the object connex series and the 3D Systems ProJet series can  be very much printed as thin layers as 16µm. These resolution of X-Y is comparable  to that of laser printers. The particles (3D dots) are around 50 to 500µm (510 to 250  Dpi) in diameter.  

The method of Construction of models can take away from several hours to  several days, depending how big the model is, method used, printing speed, and  complexity of the model. Typically, the time can be reduced to few hours  depending on the type of machine used and size. 3D printers give designers and  concept models using a desktop size of 3D printer.

iii.Finishing 

The printer produced resolution is very much sufficient for many of the applications  but the printing will be a slightly oversized version of these desired object which  can be the standard resolution and then the process of removing material can  give greater precision. Some printable polymers allow the surface finish to be  smoother and improved using chemical vapor processes. There are some of the  additive manufacturing techniques which are very capable of using multiple  materials in these course of constructing parts. These techniques are very much  able to print in multiple colours and colour combinations simultaneously. Some  printing techniques require internal supports to be built for overhanging features  during construction. These supports must be mechanically removed or dissolved  after completion of the printing. The commercialized metal 3D printers which very  much likely to involve in cutting the metal component of the metal substrate after  deposition. The very new process for the GMAW 3D printing which will allow for  substrate surface modifications to remove many aluminum components manually  with hammer. 

Applications

i.Education: New learning material: often you must want new teaching  materials but may not be able to afford to budget for them. Now their resources  can be made using a 3D printer, saving  money on your department budget.  When we will be Printing our own  learning, materials is not only cheaper  but it will be almost always quicker too.  Even though students are traditionally  taught through books and theory,  kinesthetic learners prefer to learn  through using aids and materials. 3D  printing which also allows you to bring  any of the subject matter to life as the  physical aid to engage all of your students for a very long period of time increasing  that their learning and improving their problem solving and critical thinking  capabilities.

ii. Apparel: 3D printing has spread into the world of clothing with fashion  designers experimenting with 3D-printed shoes, and dresses. When we talk about  the commercial production, Nike is  using 3D printing to prototype and  manufacture the very same football  shoe for the American football players  and the company New Balance is 3D  manufacturing custom fit shoes for all  the athletes. 3D printing has come to  the point where companies are printing consumer grade eyewear with on  demand custom fit and styling (although they cannot print the lenses). On  demand customization of glasses is possible with rapid prototyping. 

iii. Construction: With the help of 3D printers, we are able to build civil models  like prototype of building or plan structures. So that the customers can easily  visualized the models. 

iv. Dental: With the help of 3D printers, we are able to print jaws it can be a  prototype or it can be a jaw bone which can be transplanted as per the needs.  An 83-year-old British woman recently underwent the first-ever custom transplant  of a lower jaw made by a 3D printer. 

v.Medical: Medical applications for 3D printing are expanding rapidly and are  expected to revolutionize health care. Medical uses for 3D printing, both actual  and potential, can be organized into several broad categories, including: tissue  and organ fabrication; creation of customized  prosthetics, implants, and anatomical models;  and pharmaceutical research regarding drug  dosage forms, delivery, and discovery. The  application of 3D printing in medicine can  provide many benefits, including: the  customization and personalization of medical  products, drugs, and equipment; cost effectiveness; increased productivity; the democratization of design and  manufacturing; and enhanced collaboration. However, it should be cautioned  that despite recent significant and exciting medical advances involving 3D  printing, notable scientific and regulatory challenges remain and the most  transformative applications for this technology will need time to evolve.

vi. Domestic Use: The domestic market of the 3D printing was mainly  practiced by hobbyists and enthusiasts and was very little used for many of the  practical household applications which are inapplicable. A working clock was  made and gears were printed for home woodworking machines among other  purposes. 3D printing was also used for ornamental objects. Websites associated  with home 3Dprintins include coat hooks, doorknobs etc. 

Motion Configuration in 3d Printer 

i. Cartesian Configuration 

ii. Delta Configuration 

iii. SCARA Configuration 

iv. Polar Configuration

Materials used in FDM 3d Printing

Electronics 

i.Controller 

The controller is the brains of our 3D Printer. Almost all 3D Printer controllers are  based on the of the Arduino microcontroller. While a lot of variations exist. they  are exchangeable and basically all do the same thing. Now and then the  controller is a remain solitary circuit load up with chips on it, in some cases the  controller is an Arduino Mega with an extra board (called a "shield').  

ii.Stepper Motor 

A stepper motor (or step motor) is a brushless DC electric motor that partitions a  full pivot into a numerical of equivalent advances. The motor's position would then  be able to be instructed to move and hold at one of these means with no criticism  sensor, as long as the engine as deliberately measured to the application. Stepper  motor moves a known break for each beat of vitality. This beat of vitality is given  by a stepper driver and is suggested as a stage. As every movement moves the  motor a known partition it makes them helpful gadgets for repeatable arranging.  We will utilize stepper motor to move the bed carriage and different gatherings in  their individually X - Axis, Y - Axis, Z-Axis. 

iii.Heatbed 

A heated build platform HBP improves in the printing quality of the 3d model by  helping prevent warping. As extruded plastic cools it shrinks slightly. When this  shrinking process does not occur throughout the printed part evenly, the result is  the warped part. This warping is very commonly seen as corners being lifted off of  the build platform. Printing on a warmed bed permits the printed part to remain  warm amid the printing procedure and permit all the more notwithstanding  contracting of the plastic as it cools underneath softening point. The warmth bed  prompts higher complete quality that works with materials, for example, ABS and  PLA. A HBP can likewise enable clients to print without rafts.

iv.Endstops 

Mechanical switches are less complicated to implement and cheaper than  optical end stops because they do not require a circuit board and only use 2 wires  for connecting the switch. Resistors Pull up and down can put close to the main  board. Contact-less magnetic switches are called read switches. They are  proximity switches that close (or switch over) if a magnet comes close enough  (usually 1 mm or less) and open if the magnet moves away. Reed switches are  utilized as sensors in home caution frameworks to identify open windows and  doors. 

v.Stepper Driver 

A stepper driver is a motor that acts as the kind of intermediate between a stepper  motor and the controller. It streamlines the signs that should be sent to the stepper  motor keeping in mind the end goal to motivate it to move. Here and there the  stepper drivers are on independent circuit sheets that are connected to the  controller through links. Now and then the stepper drivers are on little circuit sheets  that connect straightforwardly to the controller itself. For this situation, the  controller will have space for no less than 4 of these little circuit sheets (one for  every stepper motor). Finally, sometimes the stepper drivers are soldered right onto  the controller itself. 

Hardware 

i. Linear Rods 

ii. Threaded Rods 

iii. Linear Ball Bearings 

iv. Pulley 

v. Rigid Frame 

vi. 6mm Gt belt 

vii. Couplers 

viii. Motor Mounting Brackets 

ix. X-y-z axis Carrier

Software 

i. CAD Tools 

Computer Aided Design are used to design 3D parts for printing. Computer aided  design (CAD) is where we use the computer system to assist in the creation  modification , analysis or optimization of a design. Computer aided design software  is utilized to expand the efficiency of the creator, enhance the nature of  configuration, enhance interchanges through documentation, and to make a  database for manufacturing. Computer-aided design files in the most genuine  sense are intended to enable you to effectively change and control parts in view  of parameters. Now and then CAD files are alluded to as parametric records. The  parts which are being represented as a tree of Boolean operations which are  performed on primitive shapes such as cubes, spheres, cylinders, pyramids. 

ii.CAM Tools 

Computer Aided Manufacturing, or CAM, tools handle the intermediate step of  translating CAD files into a machine-friendly font used for our 3D printer electronics.  Here we will be using a software which will be an integration of object slicing,  Generation of G codes and M codes, Object Placement and other printer  settings. Usually to turn a 3D part into a machine format, CAM software needs a  STL file. The machine friendly format that is used for printing is called G-code. 

iii. Firmware 

3D Printer electronics are controlled by an inexpensive CPU such as the Atmel AVR  processor. Atmel processors are what Arduino-based microcontrollers use. These  processors are exceptionally weak contrasted with even the normal 10 to 15-year old PC you find in the landfill these days. However, these are CPUs so they do run  primitive software. This primitive software they run is the firmware. The entire  software chain that makes the 3D Printer work, the firmware portion of it is the  closest you get to actual programming. In fact, the term for what you are doing  with firmware is called cross.