Skip to main content

3-D PRINTING WOKSHOP

WORKSHOP DOCUMENTATION

THIS DOCUMENT IS MEANT TO BE A GUIDE TO THE CONTENTS AND THE METHODOLOGY OF THE WORKSHOP, AND IS MEANT FOR INTERNAL PURPOSES ONLY

Goal of Session->

The idea and main goal behind this session is to introduce the attendees to the idea of 3-D printing as a viable and fun method of manufacturing certain items, while also extending the scope to understanding how it is a bigger part of creating a circular chain. A focus on in depth technical details is not necessary, but it is important to understand certain aspects that define the process and its parameter. Lastly, we also aim to get them started with a basic introduction into the designing process for models made out of this method of manufacturing.

Expected Outcomes of Session->

The attendees are able to->

  1. Understand how 3-D printing is an active part of the circular economy
  2. Basic understanding of the different materials used, and how they change with respect to certain design parameters
  3. Theoretical/little practical knowledge on slicing software and basic designing
  4. Understand benefits and flaws of this type of manufacturing process

Session Flow Plan->

  • Introduction
  • Getting Inspired: The idea behind 3-D printing and some examples
  • Getting Informed: Certain general and technical aspects of the Process
  • Design Process: Flow from design to deployment of the printer, to some other tips and tricks
  • Technical Demo: Technical demonstration of CURA(Slicing), and working with TinkerCAD

Part 1: Introduction

  1. Introduction to High Tech Labs-​

-Circular Makerspace for Locals to experiment, learn and make products

-We are also involved in educating the public through the means of workshops and sessions, which empower individuals to think in terms of circularity

- What is Circular economy? It is a model of reuse and reworking with existing materials in order to reduce overall resource consumption.

-Machines at HTL : Laser Cutter, 3D printer, Plastic Recycling machines (Show them the machines)

2. Introducing the Presenter​

- Name and photo on slides

- A small bit of educational background and reason why you are at HTL

- A small fun fact about yourself to connect with the crowd

3. Getting to Know the Crowd​

- Ask the participants to introduce themselves one by one, and add a fun question to break the ice and make them feel comfortable.

4. Introducing the Session​

-Introduce the session contents to the audience as on the slides

- Introduce the main goal of the session, which is to give the audience the basic understanding and application of 3-D printing, and to be able to wok with the idea and understanding of how this method of manufacturing operates

Part 2: Get Inspired

GOAL-> To inspire the audience into taking an active involvement in the workshop by showing them certain examples (pictures and some real manufactured parts) in different domains and themes, so as to emphasize on the versatility of the process, and also, about how it is a fun method!

Basic Information:

  • Explanation of how it is used in repair of items which emphasizes on circularity and life extension of products. Example taken- Dopper Bottle top (PLA)

  • Replacement part for an iron box- Emphasizes on the constraints with respect to heat, and that material has to withstand the level of heat. The usual material used is ASA.

  • Replacement of a camera battery cover- Emphasizes on the need for the material to be shock resistant and absorb a lot of force on impact. The usual material used is ABS.

  • Showing different examples of products, such as Zipper, Keyboards feet, handles, and other items, which shows the different applications of 3-D printing.

  • Inspiration can be drawn from already available databases, and different sites that exist with pre-made models available to print.

  • Cults 3D: Has action figures

  • Thingiverse: For everyday items and some quirky objects

Applications:

  • Applications: Games and Toys:
  • Can be used to create custom pieces in board games
  • Recreate damage/lost pieces instead of having to buy a new set
  • Movable toys can be made by making the design with ‘articulated’ joints-which are movable joints on the toy (Show them a piece with articulated joints available)
  • Application: Jewelry:
  • Earrings, bracelets, rings can easily be made
  • Empowers the community to start small scale businesses using this technique, including people who do not hold a technical background
  • Watch straps, and many other features that generally are complex in nature and its geometry is not easy to define, can be made by this process.
  • Application: Home Gadgets:
  • Day to day household applications can be modelled and made, which include corner shelfs, pen stands, organizers and many more.
  • Parts for custom purposes around the house that are not available in the market can be made using this process.
  • Application: Phone Gadgets:
  • Custom gadgets to make phone stands for a variety of situations, audio amplifiers, and many more attachments.
  • A very innovative and big market, considering the dependence on the mobile and it’s literally your life
  • Application: Other Purposes:
  • Christmas and many other decorations can be made, which can be reusable for multiple years
  • Small everyday objects like ear saver for masks, which many people find helpful, or a paint palate can be made
  • Swanky objects that you make as a showpiece or for fun, which are complex in nature, can be made.

Thus, the ‘Get Inspired’ section gives the audience an idea of the scope of 3D printing.

Part 3: Get Informed

GOAL-> To equip the audience with some basic principles and features of the technique and the 3D printer, which would be essential in making an informed decision on when and how to utilize this process.

Why 3D Printing (Advantages):

  • Complex objects that have intricate designs and features like holes and multiple rounded edges are difficult to manufacture using traditional techniqus and require a lot of processes, but 3D printing can manufacture them as easily as any other non-complex part.
  • Before the molds for a large-scale product for an industry is made (which is usually made with aluminum blocks and are expensive), a prototype can first be 3D printed and tested. This allows for quick prototyping with minimal costing and wastage of material, and can still allow for changes to be made in the design process. Give example of bottle opener for company(Product at HTL)
  • Since the machine handling itself does not need too much in depth technical knowledge, it is very easy to learn and make models using this and 3D modelling. The physical knowledge to operate the printer is much lesser than to operate a lathe or a milling machine.
  • It is indeed very cheap when looked into the material cost per unit and running costs of the printer per unit. This is another reason why it is preferrable, especially for industrial prototyping, as edits can be made to the design and re-printed for cheap.
  • The parts and the process is very customizable, by simply changing the 3D model, the design can be changed, and the material used can be customized to fit the application of the part.
  • There is a huge advantage of material saving, as this process ONLY prints the material that is required for the part (sometimes with supports), but no other material that needs to be cut out. This leads to very minimal wastage of material, which is a more sustainable method of manufacturing.

Why Not 3D Printing (Disadvantages) :

  • The process is very slow, as the parts are made in layers and those layers are formed slowly. Most prints with larger volumes could take an entire night, which means that manufacturing a part in large scale via 3D printing is not possible (At least for now). HTL offers overnight prints to be done!
  • There are certain problems related to the machine itself which could happen, which are not foreseeable, but are still pretty rare. For example, a blocked nozzle could lead to a print being stuck, whereas other problems like software issues or failed prints could occur. We have people at HTL who will help with this, and people who come in here are not expected to know how to solve these issues.

FAQs about 3D printing:

  • Where do I start? : This workshop was designed to be a starting point for all beginners to gain the basic understanding, an they can start printing already. There are also resources available on the internet which can explain the basics.
  • Is it expensive? : The method itself is not expensive(as explained above), and even for home applications, smaller desk printers are available which are affordable (In the range of 200-300 euros), which could be used for activities at home.
  • Is it difficult? : As seen above and will be referenced in the next few slides also, it is not a difficult process, and anyone can learn and implement this.

Hence, 3D printing can be seen to be an accessible and sustainable method of manufacturing, which is the greatest incentive for any person to use this method!

Technological Aspects:

  • The flow of processes for the manufacturing of a 3-D part occurs primarily in 3 steps (The steps will be explained in detail in the next section)-
  • Modelling
  • Slicing
  • Printing
  • We will go in explaining the process during the course of this workshop in the other direction, which is from printing to designing.
  • Print Materials classification:
  • Plastics, Metals or Ceramics can also be the base material to 3-D print a part.
  • Metals and ceramics are expensive to use and manufacture, which make it not too widely used. However, it is application based, and if the part demands the material, that can be made using specific printers (We at HTL do not have those printers)
  • The most common materials used for 3D printing are plastic based materials. There are 2 methods of printing these, which are Filament Printing (FDM), or Resin printing.
  • Resin Printing (SLA), is a process wherein the plastic is in a basin of liquid, and as the liquid is deposited, UV light cures 1 layer at a time, which will make the product.
  • The most widely used is the Filament printing (FDM) technique, which is also what we have at the HTL.
  • Fused Deposition Modelling (FDM) Printing:
  • It utilizes a plastic spool with the plastic material on it (represented by the colored unit)
  • The spool has the material type, color and temperature properties to run the machine in written onto the spool.
  • This spool is mounted onto the 3d printer, either on the side or on the back.
  • The plastic is heated up to about 200 degrees Celsius, by the nozzle, which turns the plastic into a liquid.
  • The nozzle then layers the liquid in the shape of the part, as it is deposited onto the build plate.
  • The build plate is made via a rigid construction, and is heated to about 50 degrees Celsius. This creates a sticky attachment to the plastic, which will prevent warping of the plastic part).
  • The part, after completion can then be taken out and removed from the build plate.
  • The objects that are made, are made from the bottom to top, and layers are constructed horizontally.
  • The printer can only move in the X,Y and Z axis, making it a 3-axis movement. This movement is depicted in the G Code of the part when it is developed by the slicing software.
  • Materials Used in FDM (At HTL, we only have PLA and ABS)
  • PLA (Polyactic Acid): This is the most commonly used material, as it can be printed at relatively lower temperatures. It can be biodegradable (in a A20-year span) as it is an organic component. PLA can be made from anything that is starchy in nature, like corn flour. This is recyclable, as it can be melted and then reused again for the process, although it might incur minor changes in properties every time it is melted and reused. It has a low heat resistance, and is also slightly brittle (can be broken with force).
  • ABS ( Acrylonitrile Butadiene Styrene) : This is a relatively tougher material, and has a pretty high impact resistance, so it can be used in applications where there is rough use. It also has a very high heat resistance, so it can be exposed to higher temperatures. However, it is not good in cold temperatures, and might break easily when exposed to low temperatures. Since it contains styrene, whose vapors can be toxic, this does provide a certain health risk when manufacturing. This is why you always have circulation of air in and out of the room when printing with ABS.
  • TPU (Thermoplastic Polyurethene): This is a specialty plastic, which can be stretchy and can be deformed in the elastic region pretty easily, and can be used as a replacement for hard rubber. It has good shock absorption capabilities and vibration damping, which is why it could be useful for something like mobile phone covers. However, the print speed for such a plastic is low, and it absorbs a lot of moisture over time, which may make the part get ‘clogged’ over a period of time.
  • PET (Polyethylene Terephthalate): This material can be derived from recycling plastic bottles, as they are made from PET. This has a decently high temperature resistance, so it can be used in applications that are probably used in regions of moderate operating temperature.
  • ASA (Acrylonitrile Styrene Acrylate**):** This is a high impact, high heat/chemical resistant type of plastic, and can commonly be found in applications with very high operating temperatures, like iron boxes and other items. This material is more costly however, and since it also contains styrene, has the problems of being a health risk. It could also warp during the printing phase, which makes the final product a little distorted from the model.

Thus, in this section, we have seen some of the technological aspects relating to the process, especially the materials used, and its different use cases. This will give the audience an idea of what materials to use depending on application.

Part 4: Design Process

GOAL-> To equip the audience with a basic understanding of how a part is designed to be 3-D printed from the model conception phase, and to give them certain tips and tricks that they can utilize when making the part.

We have already seen the flow chart of how a model is conceived, which starts from the modelling phase, then slicing, and finally printing the part. To understand what they look like->

  • Modelling : Where the model is created on a computer using a 3D modelling software. There are multiple software that can be used depending on the level of complexity of the designer. For starters, most models of general parts are already available in open-source databases. These files are then converted to an STL format for slicing.
  • Slicing: This is a separate computer software that slices the model that is made into different layers, through which the parameters such as temperature to print, material and many more can be changed to get different integrity of the print. This is an important part, as the slicing will determine the printing process. The output of this is the part written as a G-CODE (It is a code rendered by the software automatically by the slicer, which contains the coordinates of all 3 axis during each step).
  • Printing: Finally, the G-code of the sliced part can be sent to or inserted into the 3-D printer, which will automatically print the part. Not much intervention needed here, apart from keeping an eye on the printer in intervals to make sure that there is no problem.

Supports:

  • Let us assume that there is a part designed with sharp angles or additional fittings that have to be printed on one side vertically. There is a high chance of the printer printing in the air if there is no base support on which it can stand, which will create problems like failed prints, and a lot of filament will be unnecessarily wasted.
  • To counter this, extra supportive material (known as supports) is given, and especially when there are sharp angles between surfaces that are greater than 45 degrees.
  • This is of different material that can be removed from the main part after the product is completed. The supports are usually of different color and material also, which make them distinguishable post printing.
  • There are different materials used for supports, so they can be extracted easily. Some of them include a water-soluble material, which makes it very easy to remove it.
  • The supports are automatically made and constructed by the slicing software, and does not need any intervention from the designers side to add them into the model.
  • As an alternative to using supports, we can change the orientation of the way we print this can be changed to not have the need for supports. We could also redesign the parts to not have angles greater than 45, by using rounded fillets.

Design Tips and Tricks:

  • Not making parts with bridges higher than 1cm without supports
  • The minimum diameter of holes must be 2mm
  • The minimum diameter for any pins used must be 3mm
  • The minimum diameter wall thickness must be 0.8 mm.
  • The minimum values are kept to allow for the tolerance and the allowance of the process itself. It can be explained by taking into mind the thickness of material the nozzles spew out, and the range with which it spews out.
  • Depending on the resolution(The smallest thickness that can be printed), there are other design considerations that are specific to that printer that must be kept in mind.
  • All these constraints are mainly to avoid the technical problems as stated above, and to avoid the waste due to 3D printing which may occur from failed prints and waste filament.

Practical Information on HTL:

  • Free Open labs: Every Thursday and 1st Saturday of the month from 18:00 to 22:00
  • Reservations can be made for 10 euro an hour
  • 3-D printer cost: 0.1 euro per gram, with a minimum of 5 euro.
  • Document is available with practical information!
  • Email ID is given (give them time to note it)
  • Make a small pitch for donations to the HTL on the basis of our projects and the idea behind which we operate, along with a call for volunteers.

Part 5: Technical Demo

GOAL-> To give the audience a small technical demonstration and equip them with the basic skills to use both the slicing and the modelling software themselves.

Slicing Software: Ultimaker Cura

  • This is a free software, that is made by Ultimaker, It is an open-source software that can be accessed by anyone.
  • Explain basic interface, and how to open a model in it.
  • Explanation of:
  • Adding a printer (adding printer model base on which printer is being used). The printer at HTL is Dreamer NX
  • Controlling material of print: This will give us presets on which temperature the process will be controlled at
  • Once the ‘Slice’ button is clicked, it will slice the structure into layers. The time taken to print and the weight of the model will be shown.
  • We can change In Fill percentage, which is the grid like structure that the model is filled with. It is possible to change the density, pattern of the infill. The average infill used is about 70%.
  • Special setting can be optimized, to change the wall thickness, number of layers, print speed also (lower print speed will endure a much better precision, faster speed will give a lesser accuracy). Supports can also be turned on and off, and there are many more features that can be edited.
  • All we have to do is save the G Code(automatically generated) on a USB and insert it into the machine, or even wirelessly.

Modelling Software: TinkerCAD

  • This is another free software by Autodesk, which is a very basic software with preset shapes, and only the size can be changed to get the specific dimensions.
  • Basic demonstration of how to use shapes, use the group function, subtract and hole functions
  • Working with the audience on creating a model of a wrench, which is easy to create. Step by step process would be shown via a projector, which the audience would follow, to get a familiarity of the software.

Thus, the audience is able to grasp the idea of a slicing software and a modelling software, and the different parameters that go into it.

The workshop ends with a feedback session of 4 things

  • Content of Workshop
  • Presenter and their way of presenting
  • Any changes to any aspect of the workshop, or any other sort of content they were expecting
  • General feedback on High Tech Labs

Questions asked during sessions->

  • Can PLA be recycled from failed prints?
  • How do you calculate the correct level of Infill that is required for a part?

PAGE 1