Additive Manufacturing

1. Objective

2. Introduction to 3D printer

  • 2.1 Advantages of AM in Prodcution
  • 2.2 Disadvantages of AM in Production
  • 3.0 Principle of 3DP (3D Printing)

  • 3.1 How it works
  • 3.2 Pro
  • 3.3 Con
  • 4.0 Data exchange file formats for AM

  • 4.1 Characterisitcs of STL
  • Quality issues due ti tessellation
  • 5.0 Supports

    6.0 Robotic Arm

  • 6.1 Sketch Idea
  • 6.3 3D CAD
  • 6.3.1 Head
  • 6.3.2 Shoulder Join
  • 6.4 2D Drawing
  • 6.5 3D Print
  • 6.5.1 Cura
  • 6.5.2 Printing properties
  • 6.6 Assembly
  • 7. 3D Scan
  • 6.0 3D Scanner

    1. Objectives

    In this assignment, I have designed a robotic arm and then 3D print some of theparts that culd not be made subtractively. Moreover I tried a iSense 3D scanner.

    2. Introduction to 3D Printing

    Fig 1.0.1 : What is addictive manufacture? Resource: 3d hubs

    Additive Manufacturing is know by many names: 3D Printing, Rapid Prototyping, Rapid Tooling, Rapid Technologies, Rapid Manufacturing, Advanced Manufacturing, additive Fabrication, Additive Layer Manufacturing, Direct Digital Manufacturing and Direct Manufacturing. Today additive manufacturing focuses on features such as geometric freedom and speed is not he sole determining factor.

    Unlike most conventional manufacturing techniques, Additive manufacturing forms oject bz building matter up, rather than removing it.

    Additive manufacturing technologies are use to manufacture: Prototypes, tools and production parts.

    2.1 Advantages of AM in Production


  • Increased geometric freendom : under cuts, function integration and new deisgn possiblities
  • Production of individual parts (mass customization)
  • Spare part production "on demand"
  • Parallel production of different parts
  • Constant effort for set-up
  • Low maintenance costs
  • Tool free or non wearing operation
  • Reduction of storage costs and capital tie-up costs
  • 2.2 Disadvantages of AM in Production


  • Restrictions regarding wall thicknesses , hole diameteres and clearances
  • High surface roughness in raw state
  • Support structures necessary
  • Slow manufacturing process
  • High energy costs
  • Material selection is limited
  • (up to now) not suitable for mass production
  • parts qulities difficult to quantify
  • 3.0 Principle of 3D printing (3DP)

    3.1 How it works

  • A wire shaped material is melted in a high temperature nozzle
  • Plotter mechanism
  • Hard lazers of plastic or metal filaments can be created
  • 3.2 Pro

  • Low cost
  • Multiple jetting possible
  • 3.3 Con

  • Slow process
  • Inconsistent material due to construction in layers
  • Machine suppliers: Most common technology for desktop 3d printing.

    4.0 Data exchange file formats for AM

    This is a very common way to save your 3D CAD model and there are some charteristics and what can be wrong with this alogorithm.

    LMI, VERML, CS, RPI and STL,etc

    STL - orifinally STeroLithograpy, today Surface Tessellation Language also known as Standard Triangulation Language

    4.1 Characterisitcs of STL

  • Neutral data format
  • Developed in 1987 for 3D Systems
  • Orifinally developed for stereolithography applicatrions
  • Easy Mathematical description of the faceted surface
  • Simple slicing algorithm (operations on traigles)
  • Ability to splot models
  • Wide range of input ( nearlz all 3D representations acceptable
  • Not officially standradized
  • Widespread use
  • 4.2 Quality issues due to Tessellation

    After tessellation following erros can occur:

  • 1. Wrong proemtation of triangles
  • 2. Wrong contour
  • 3. Missing triangles
  • 4. Intersecting triangles
  • 5. Too fine/coarse triangulated
  • 5.0 Supports

    Supports are used when models have sttep ovehangs or unsupported area

    A general rule of thumb is that most printes can support ovehang angles less than 45 degrees

    6.0 Robotic Arm

    6.1 Sketch Idea

    First of all I sketeched my idea what I am going to 3D model and some of the feutures of the robotic arm.

    6.2 Part List

    I am planning to use a 3d print and laser cut a plywood to fabricate the robotic arm.

    Part list:

  • Arduino Uno
  • Cables
  • M3 nuts and screws
  • 3x Servo MG996R
  • 3 mm and 6 mm thickness plywood
  • PLA
  • 6.3 3D CAD

    3D CAD of the robotic arm that I am going to build.

    6.3.1 Head

    To model this is simple you have to design so that it can hold the servo motor and assembly this to another part.The feuture I used to model this head part is boss extrude, mirror, filet and cut extrude.

    6.3.2 Shoulder Join

    As you could see this object cannot be produced because the inside of the part should be cut and a CNC milling machine head tool might be to large to cut this.

    6.4 2D Drawing

    After I have modeled the 3D CAD using solidworks, I made a new 2d drawing and put all the parts that I want to laser cut.

    6.5 3D Print

    6.5.1 Cura

    Cura is the software to generate the g-code of a 3d printer and set the properties.

    6.5.2 Printing properties

    It is time to print two parts of the robotic arm, the head and he shoulder join and I was printing with Ulimaker 2+. Printing PLA is quite easy because it melts in a low

    Ultimaker 2+

    Print setup: Custom

  • Material:PLA
  • Nozzle : 0.6 mm
  • Layer height : 0.25 make sure that the layer height is less than the nozzle size and this will effect the surface roughness of the product
  • Wall thickness: 1mm
  • Top/ Bottom thickness : 1mm
  • Infill density 15 % depends how strong you want the material and the printing time is.
  • Enable reaction is to checked to make sure there is no extrusion when nozzle moves from one point to another.
  • Print speed : 60 mm/s how fast to print
  • Travel speed : 120 mm/s
  • Enable cooling
  • Gernerate support
  • Support patern Zig Zag
  • Support distance = 5
  • Start to print and it takes arround 3 hours to print.

    Remove the support from the material

    6.6 Assembly

    Assembly the 3d parts to the plywoods with m3 screws.

    Finally we have a robotic arm!

    7.0 3D Scan

    7.1 A Chair

    The assigment is to 3D scan an object.

    The 3D scanner that I use in our FabLab is called iSense which is attached to an Ipad.

    This is my first experience using a 3d scanner and the result is not that bad.

    We will have to rotate 360 degree and move up and down to scan the object.

    The result for shaded View.

    The result for x-Ray.

    The result for colour view.

    This is the overall view of my first experience of using a 3d scanner.

    7.2 My dad

    The harware I used to 3D Scan was actually my Iphone x with ScandyPro software in IOS.

    Then I tried to 3D print it and the following picture was the result

    8. References



    9. Download

    Robotic Arm 3D CAD

    3d Scanner file