Pre-FAB Academy

Week 4

 

Day 1

 

We have approached our final week of the Pre-Fab Academy Workshop. This week evolves in applying the knowledge gained so far to develop a main project. Franc left to fab lab cochin and Luciano is going to be guiding us through the process. Luciano began today's session with introduction to design thinking concepts.

 

Product design at fab lab must be such that the product is not available in the market at a low cost, the product must solve a personal problem even if it doesn't solve big problems. Luciano asked to come up with ideas to solve your day to day problem or some product ideas that are executable in a week time frame. Also, the project must use atleast three processes in the fablab.

 

I had a few ideas which I liked to try:

 

1) Vertical Farming - A modular farming method making use of Hydroponics, upcycling and Automation.

2) Personalised Wrist watch - I am a big fan of customized products, to be able to design a watch from scratch would be great.

3) Juke Box - A small musical Juke Box with a simple rotation piece and dancing light with music.

 

Designing the product

 

Mass manufacturing is loosing it's grip as mass manufacturing does not design product's to represent each individual and is designed to represent an imaginative person. So, product designing to represent each individual is gaining momentum. With in a week, the product might not be developed. But, the process of developing the product is more important that the final product. The first prototype won't be perfect but keep adding and perfect the product as you go.

 

I have decided to make a wrist watch.

 

Design Cycle:

 

Luciano told that Design thinking process should be:

 

 

Ask: Asking includes doing personal research on the problem for the solution, asking friends and tutors for gaining more knowledge to solve the problem.

 

Imagine: Different solutions are sought out using brainstorming and divergent thinkings. Think in different angles and break down the main problem into smaller problems to generate ideas.

 

Plan: Here, comes the actual thinking process of how to solve the problem identified. Time frame is set and the problem solving is planned.

 

Create: The first prototype is created. The prototype won't be perfect or the final product.

 

Improve Cycle: The product design doesn't end at creating the product. The first prototype is further improved and new features are added out.

 

Brainstorming:

 

Brainstorming session is important in idea generation and problem identification. Luciano, conducted a short brainstorming activity of “What's missing in the Lab”.

We came up with a few problems we had at the lab, including storage issue of vinyl rolls, low light at soldering stations, video equipment's not set up, etc.

The problems were accessed and the solutions were found out. Few problems had solutions which could be brought from outside (like the sandblasting not working situation). Other's like storage issue of vinyl roll could be resolved with solutions made at fablab facility.

 

Fabrication of Fabduino

 

Fabduino is a Fabable Arduino Compatable Board.

Download the eagle board and schematic files along with the png files of top, holes and outline. Mill the top, holes and outline using roland modela. Stuff the components (atmega 328p, push button, resistors, capacitors, resonator, FTDI headers and connectors). Soldering the Atmega 328 pins is a hectic job if each legs are tried to solder one by one, so instead after placing and fixing the chip, short the legs all together with solder. Later, remove all the solder at once using a copper braid to get a clean soldering of each legs.

 

Programming the Bootloader

 

This is done with the Arduino IDE. Connect the ISP pins (5V, GND, SCK, MISO and MOSI) from FabISP to Fabduino board. Also, solder a wire from RESET pin of Fabduino to RESET pin on the FabISP or hold the wire there during the programming. Once this is done, plug FabISP into the computer and open Arduino IDE from the terminal using Sudo. Go to Tools and select Arduino Pro or Pro Mini as the Board, pick the external clock option also. Since we have external resonator too, there is no need to install board.txt file. And then Burn Bootloader.

 

 

Day 2

 

Today, Luciano introduced Rhino Software. Also, we learnt to operate Shopbot.

 

Rhinoceros is 3D modeling software that can be used in a variety of ways and for very different purposes. It is primarily a surface modeling tool, but has many related functions as well. It is an easy to use software. I learnt how to create surfaces and 3D objects from 2D objects. Rhino has objects that consists of two or more surfaces bound to form 3D objects, this is called poly surface. Solids formed by Rhino has surfaces with zero thickness just like a shell. There are four views in the Rhino workspace (top, botton, side and perspective). It is easy to switch between the views or see all the views at a time. A few exercises were done to familiarise with Rhino software.

 

ShopBot

 

Shopbot is a large milling machine for cutting, phrasing and shaping wood and plastic in various 3D sizes.

ShopBot Steps:

 

1. Open Partworks and Create a new file

   Define material size and units

2. Import file to Partworks or make your design there.

3. When the design is ready you should make toolpaths for the machine.

   Selecting Tool paths.

    

   1. 1. V-Carve: V-Carving Tool path form which is used to specify the type of carving required, tooling details, cutting parameters and name for the tool path.

          

      2. Profile: Profile Machining options provide the flexibility for cutting shapes out with optional Tabs / bridges plus an Allowance over / undercut to ensure perfect edge quality.

          

      3. Pocket: Pocket Tool path form for machining pockets. These tool paths automatically compensate for the tool geometry - diameter and angle.

          

      4. Drilling: Drilling allows the centers of selected closed vectors to be drilled to a specified depth. The Tool database includes an option to specify the Drill diameter and cutting parameters.

          

      5. Texturing: 3D Texture Machining functionality makes carving stunning sculpted surfaces very simple and perfect for making custom panels and interesting signage. Textures can be calculated inside any selected vector boundaries or if nothing is selected the complete job size.

          

      6. Clearance: The "save" height for the Z-axis.

         Select Depth: Start Depth (D) specifies the depth at which the tool path is calculated, allowing Engraving to be machined inside a pocket region. Cut Depth (C) is the depth of the pocket or profile tool path relative to the Start Depth.

Do not cut deeper than the material thickness.

1. 1. • Select tool

      • Clicking the Select button opens the Tool Database from which the required Tool can be selected.

All 4 of the cutter types (V-Bit, End mill, Ball nose, Engraving) are supported and the toolpaths will automatically compensate for the geometry of the selected tool.

1. Save the tool paths (.shp file)

2. Save the project. (.crv file)

 

I found the following video tutorial helpful to know how to Set up the machine, Change the Bit and turn on the shopbot.

 

ShopBot - How to Use

 

Luciano used Rhino to create a design to be milled in ShopBot and as a group taught us how to set up and mill the piece in Shopbot. The final piece is shown in the image.

 

 

Day 3

 

Diwali Holiday, doing documentation was the catch up plan.

 

Day 4

 

Today, we poured Oomoo 25 silicone rubber for mold into the milled mold we created during week 2. It has a convinent feature of one is to one by volume mix ratios. Also, it has a pot life of 15 minutes and cure time of 75 minutes. These materials are highly toxic and can cause allergies. So, while handling them always wear apron and gloves. The oomoo part A and part B are mixed in 1:1 ratio by volume. Take care that the mixing is done thoroughly. Also, a black dye was added to the mixture. While mixing take care that air bubbles are not trapped. After mixing transfer them to the molds. Tap the molds to remove the air bubbles that are trapped in the bottom. The silicone rubber was not curing after 75 minutes. So all the mold are just trash now.

The reason might be either the silicone rubber stayed in the shelf for too long or the dye added might have changed the properties of the material leading to not getting cured.

The material has a shelf life of only 4 to 6 months and with the temperature and humidity the shelf life gets reduced.

Later, Luciano explained design guidelines with the mold created by him in rhino. They are

1. Draft Angle – By providing a draft angle it becomes easier to remove the material from the mold by providing certain draft angle to the design.

2. Clearance area from edges and top of the mold – Providing a clearance area is necessary since there is a chance of the mold melting off if the edges and tops are thin.

3. Bit selection – The Bit type should be flat head if more flat surfaces are involved. For curved surfaces, the bit type should be ball headed.

 

 

Day 5

 

During the brain storming session earlier this week, problem with sandblaster not working was brought forth. So, Luciano was figuring out the problem with the sandblaster and trying to set up the sandblaster. Luciano told that in a standard inventory we have a smaller compressor for sandblaster and he have never seen this compressor in any other inventories. He suggested to replace the compressor with a smaller compressor. He also suggested that the Dimension 3D is not necessary in the lab and we could buy 10 ultimakers with the same cost !!! So he suggested to replace that too to get enough resource to buy other necessary commodities for the lab. I think something like a tailoring station would attract more ladies into the fablab. It's unfortunate that the one month journey is coming to an end. I would definitely keep in touch with Luciano and Franc. In such a short span of time, I must say that I have gathered so much of knowledge. I would love to continue the journey and inspire more people (especially women) to make and tinker.

 

 

Final Project

 

My final project was to make a wrist watch custom made and designed. The processes involved was computer aided designing, 3D printing, Electronic fabrication and production. Even though I could not complete my project, I'm pretty happy that I did try out all the processes to create the final product.

 

Strap: The strap was a series of chains linked together. My Goal was to print it as a piece inorder to avoid assembling the pieces individually. I was pretty successful in designing the chain as such printed using ultimaker instead of dimensions. I gave enough clearance space between links and the casing so that the printing doesn't make them stick together. The whole designing was done using Rhino software. I found it pretty good to toggle between different viewpoints. The case had a dimension of 3.5cm by 3.5cm.

Initially to check out whether the links are coming up pretty good and movable, I did a test print of a small section of the strap. I found out that the links were stiff and needed more clearance space between the links.

 

Electronic Fabrication and production: I used eagle software to make the pcb. I took reference of a few projects already done and uploaded in instructables. The idea was to make use of 24 led's to indicate Hours and Minutes. Also to include 4 led's to indicate one to four minutes. I was not successful in milling the board, since the smd package used were really small (not 1206) and close by. I tried to re-mill the board after increasing the trace width and milling with 0.01 sized bit. Even this was not successful. Later, I also tried designing a smaller version of wrist watch where time is indicated using 2 led's and binary concept. But I couldn't bring up the idea into reality.

 

 

 

Check out my Sketch fab Account for the .stl files

 

Nisha-elsa SketchFab