<. <br>
It was fascinating to see how clearly pulse pattern shown in the oscilloscope tells you "A" in ASCII code. If you are fluent in machine language (or if not by just making a reverse-engineeing program), you can basically decode what's being communicated from change of current/volatage.
####Objective <br>
Make (design+mill+assemble) something big (~meter-scale)
####Metrics <br>
**A. Designing part** <br>
* Base design: Shelf. I followed [this](https://www.youtube.com/watch?v=VZU_Jpyyc5M&t=1086s "this") tutorial as my reference and changed parameters a bit.
* Software: Fusion 360 (most 3D design), Rhino (converting 3D design to 2D design), and Aspire (converting dxf to shopbot extention).
**B. Milling part** <br>
* Milling machine: Shopbot
<br><img src="./shopbot_still.JPG" alt="laser_module" width="500"/>
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* Endmills: 1/8 endmill
* Material: OSB (Oriented Strand Board)
* Software: Shoptbot's standard software
####Protocols and results <br>
**A. Design part** <br>
1. Determine a basic design. I decided to make a shelf (, risking myself considered least creative). Reasons:
* I wanted to focus on learning how to make something *big* instead of how to design some cool complex stuff on Fusion, which is nice but not the objective for me. I would experiment the latter on laser cutter.
* I want to make a beehive box for my final project for/with the communities in the Amazon. Thus, testing and understanding how easy it is to cut and assemble these simple box structure was important to experience.
<br><img src="./3D_shelf.JPG" alt="laser_module" width="500"/>
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2. Draw a 3D shelf design on Fusion.
3. Introduce dogbones.
<br><img src="./dogbones.png" alt="laser_module" width="500"/>
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4. Introduce fillets for smooth edges.
5. Export the data as dxf and edit the tool paths on Aspire. It did not work, because the data was still 3D. I had to use Rhino in between for the 3D-2D conversion (with a great help of Joon).
<br><img src="./rhino_2d.png" alt="laser_module" width="500"/><br>
6. Use different setups for countours, inner holes and inner pockets. Export the data as shopbot extention (.sbp).
**B. Milling part** <br>
1. Use the above-mentioned sketches.
2. Set up an OSB.
3. Put plastic nails using the air gun.
4. Set up the parameters (i.e. rpm=18000). Adjust the XY origin. Do a dry run with Z = 2 inches. Calibrate the Z position using the steel plate. Hit the run button.
5. Overall it went well, but when the machine was cutting the last few parts, the board was shaking a bit as I had cut out most of the parts (even though there were tabs). I stopped running the machine, and put several additional plastic nails around the remainder part.
6. Finish and clean up.
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**C. Assembly part** <br>
1. After milling, I first removed the residuals on the edges by sand paper + hammer. Then I smoothened all edged using a machine grinder (sander?).
2. I assembled them. I had to use hammer to git the joint part, but I did not struggle much. Was that because of the dogbone joints or because I grinded the edges?
3. I realized that on the 3D model, I did not take the surface assymetry (one side is smoothier while another side is rougher) into consideration. As a result, the right side of my shelf became a bit rough on the exterior side. Other than that, I am happy with the shelf.
<br><img src="./shelf_and_takeo.JPG" alt="shelf_and_takeo" width="500"/><br>
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[original files](https://hu-my.sharepoint.com/:f:/g/personal/ttokunari_mde_harvard_edu/Eo_MW5iJhp1GvL7Oqn-jOrYB6G4nvFlrPQ0QWN5hT0okVg?e=J0TZIo "original files") <br>
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