Jekyll2018-07-06T16:21:15+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/Andrew Sleigh—Fab Academy 2018Andrew Sleigh20 — Should you do Fab Academy?2018-07-06T00:00:00+01:002018-07-06T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/podcast/2018/07/06/podcast-20<p>To wrap up the series, I reflect on the whole experience, and give my verdict: would I recommend Fab Academy to others? I also talk about why coding is so hard, learning how to learn, and how useful it is to be uncomfortable. I hope you enjoy this episode, and enjoyed the series. I’ll see you on another podcast soon.</p>
<audio src="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep20.mp3" controls="" preload=""></audio>
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<p><a href="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep20.mp3">Direct link to mp3</a></p>
<p>Subscribe: <a href="https://itunes.apple.com/gb/podcast/unreliable-devices/id1340450476">Apple Podcasts</a> / <a href="http://fab.academany.org/2018/labs/fablabbrighton/students/andrew-sleigh/podcast.rss">RSS</a></p>
<hr />
<p>Podcast artwork uses an <a href="https://thenounproject.com/term/hand/930971/">illustration</a> by <a href="https://thenounproject.com/analalora/">Ana María Lora Macias</a>, licensed as Creative Commons CC-BY.</p>Andrew SleighTo wrap up the series, I reflect on the whole experience, and give my verdict: would I recommend Fab Academy to others? I also talk about why coding is so hard, learning how to learn, and how useful it is to be uncomfortable. I hope you enjoy this episode, and enjoyed the series. I’ll see you on another podcast soon.Week 20 - Project Development2018-06-20T00:00:00+01:002018-06-20T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/assignments/2018/06/20/wk20-project-development<p>Presentation slide and video for my <a href="/2018/labs/fablabbrighton/students/andrew-sleigh/final-project">final project</a>
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<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/presentation.png" alt="Presentation draft" /></p>
<p><a href="/2018/labs/fablabbrighton/students/andrew-sleigh/presentation.png">Open image ></a></p>
<video src="/2018/labs/fablabbrighton/students/andrew-sleigh/presentation.mp4" controls="" preload=""></video>Andrew SleighPresentation slide and video for my final project19 — What I’ve learned about podcasting2018-06-06T00:00:00+01:002018-06-06T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/podcast/2018/06/06/podcast-19<p>I started doing this podcast as an experiment, a different way to engage with Fab Academy, and a learning exercise. As we get to the end of the series, here’s what I’ve figured out.</p>
<audio src="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep19.mp3" controls="" preload=""></audio>
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<p><a href="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep19.mp3">Direct link to mp3</a></p>
<p>Subscribe: <a href="https://itunes.apple.com/gb/podcast/unreliable-devices/id1340450476">Apple Podcasts</a> / <a href="http://fab.academany.org/2018/labs/fablabbrighton/students/andrew-sleigh/podcast.rss">RSS</a></p>
<hr />
<p>Podcast artwork uses an <a href="https://thenounproject.com/term/hand/930971/">illustration</a> by <a href="https://thenounproject.com/analalora/">Ana María Lora Macias</a>, licensed as Creative Commons CC-BY.</p>Andrew SleighI started doing this podcast as an experiment, a different way to engage with Fab Academy, and a learning exercise. As we get to the end of the series, here’s what I’ve figured out.Week 19 - Dissemination2018-05-30T00:00:00+01:002018-05-30T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/assignments/2018/05/30/wk19-disemination<p>My dissemination plan, and drafts of my final project presentation</p>
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<h2 id="dissemination-plan">Dissemination plan</h2>
<p>My project is primarily for my own personal use, however, I’d like to make use of sharing platforms so that others can build on it and perhaps help me improve it.</p>
<p>I’ll write up a version of my project notes as an Instructable, to be posted on <a href="https://www.instructables.com/member/Andrew%20Sleigh/?publicView=true">my Instructables profile</a>.</p>
<p>If we can get the Fablab gang together for a Maker Faire trip, it would also be great to take it to Maker Faire UK.</p>
<p>## IP and licensing</p>
<p>I have no intentions for this to be a commercial project. It also draws heavily on previous work shared under open source licences. I would also like others to be free to develop it under simple non-restrictive terms. The code includes many parts shared under explicit licences (included in the header sections of the Arduino sketch files, for example), but also snippets posted to the Arduino forum.</p>
<p>The bulk of the non-original code is taken from the MP3 library I’ve used (<a href="https://mpflaga.github.io/Sparkfun-MP3-Player-Shield-Arduino-Library/index.html">SFEMP3Shield</a>), which includes the following licence:</p>
<blockquote>
<p>This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.</p>
</blockquote>
<p>According to the <a href="https://www.arduino.cc/en/Main/TermsOfService">terms of the Arduino forum</a>, contributions there are shared under the <a href="https://www.arduino.cc/en/Main/ContributorLicenseAgreement">Contributor License Agreement</a>. This agreement includes the following clause:</p>
<blockquote>
<p>You hereby grant to Arduino and to recipients of software distributed by Arduino a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Your Contributions and such derivative works.</p>
</blockquote>
<p>I want to maximise others’ ability to make use of my work in whatever form they wish, including commercial, unattributed form. So for my needs, a permissive licence such as the <a href="https://opensource.org/licenses/MIT">MIT Licence</a> is the best option, and one which I believe meets my obligations for code I have used myself. I plan to use this license for all design files and source code:</p>
<blockquote>
<p>Copyright 2018 Andrew Sleigh</p>
</blockquote>
<blockquote>
<p>Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:</p>
</blockquote>
<blockquote>
<p>The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.</p>
</blockquote>
<blockquote>
<p>THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.</p>
</blockquote>
<h2 id="draft-presentation">Draft presentation</h2>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/files/dissemination/draft-presentation.png" alt="Presentation draft" /></p>
<p><a href="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/files/dissemination/draft-presentation.png">Open image ></a></p>
<video src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/files/dissemination/draft-presentation.mp4" controls="" preload=""></video>Andrew SleighMy dissemination plan, and drafts of my final project presentationWeek 18 - Applications and Implications2018-05-30T00:00:00+01:002018-05-30T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/assignments/2018/05/30/wk18-applications-implications<p>My plan for a final project.</p>
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<h2 id="my-proposal">My Proposal</h2>
<p>A music playback device that incorporates the rough industrial aesthetics of 1970-80s sci-fi set design, with the ‘slow’ user interface of physical music media. The device is in part a love letter to sci-fi prop design, and a response to the choice-paralysis and devaluing of music caused by ubiquitous, immaterial, on-demand music.</p>
<h3 id="what-will-it-do">What will it do?</h3>
<ul>
<li>Play back music from physical ‘media’, in which one album or playlist is represented by one piece of media.</li>
<li>The media will be ‘keys’, with an identifying pattern of holes that can be read by the device to identify which piece of media has been inserted.</li>
<li>Music will be stored not on the media, but on an SD card in side the device, pre-loaed with directories of MP3s corresponding to each media ‘key’</li>
<li>There will be basic playback controls on the device to allow pausing and skipping of tracks, but not the selection of albums</li>
<li>There will be screen showing basic information such as artist name and album title</li>
</ul>
<h3 id="whos-done-what-beforehand">Who’s done what beforehand?</h3>
<p>Many projects exist to use platforms like Raspberry Pi to build MP3 players.</p>
<p>There is a commercial project, Qleek, https://www.qleek.me/#/about which uses a similar idea of artificially tying digital music back to a piece of physical media
There are many DIY projects to incorporate MP3 players into old casings, such as vintage radios</p>
<p>However, I’m not aware of a project that uses this punchcard-style method to key the media, or of a project based around an industrial/sci-fi style casing.</p>
<p>The project uses a breakout board (for the SD card reader and VS1053 chip) and MP3 playback library, which handles much of the low-level file handling and audio playback work.</p>
<h3 id="what-will-you-design">What will you design?</h3>
<ul>
<li>A casing for the project</li>
<li>Physical media</li>
<li>An internal mechanism to hold the electronic components, controls and circuit boards</li>
<li>Circuit boards for the media identification components (photo-interrupt sensors), playback controls, and microcontroller board</li>
<li>Software to control media identification, music playback, user controls and screen interface</li>
</ul>
<h3 id="materials-and-components">Materials and components</h3>
<p>Where I’m buying components or raw materials, a price is given below. Otherwise, parts will be made in the lab.</p>
<p><strong>Casing</strong></p>
<ul>
<li>2mm x 600mm x 400mm Anodised aluminium sheet (£8 from sheet metal supplier, made in the lab)</li>
</ul>
<p><strong>Media</strong></p>
<ul>
<li>Laser-cut acrylic, IR-opaque (lab supplies, made in the lab)</li>
</ul>
<p><strong>Physical controls</strong></p>
<ul>
<li>Volume encoder (£1, eBay)</li>
<li>Volume knob (TBC, likely bought)</li>
<li>Cherry MX Brown switches (£4, eBay)</li>
<li>Button keycaps (TBC, likely bought)</li>
<li>128x64 OLED Screen (£3, eBay)</li>
</ul>
<p><strong>Internal structure</strong></p>
<ul>
<li>Acrylic frame (lab supplies, made in the lab)</li>
<li>3D-printed brackets (lab supplies)</li>
<li>Bolts (lab supplies)</li>
</ul>
<p><strong>Circuits</strong></p>
<ul>
<li>Media identification board (made in the lab)</li>
<li>Media identification sensors (photo-interrupt switches, £4, eBay)</li>
<li>SD card and MP3 playback board (£25, Adafruit)</li>
<li>Playback controls board (made in the lab)</li>
<li>Main microcontroller board, likely to be based on n ATMega32u4 (made in the lab)</li>
</ul>
<p><strong>Power supply</strong></p>
<ul>
<li>5V DC adapter (salvaged from an old device)</li>
</ul>
<h2 id="what-processes-will-be-used">What processes will be used?</h2>
<p><strong>Circuits</strong></p>
<ul>
<li>Circuit design in Eagle</li>
<li>Circuit milling on milling machine</li>
<li>Soldering of components</li>
<li>Testing using lab test equipment</li>
</ul>
<p><strong>Casing</strong></p>
<ul>
<li>Box net design in Illustrator</li>
<li>Outline an score line milling on milling machine</li>
<li>Finishing, folding and assembly by hand</li>
</ul>
<p><strong>Internal structure</strong></p>
<ul>
<li>2D design in Illustrator</li>
<li>Cut on laser cutter</li>
<li>3D design in Fusion 360</li>
<li>Printed on Cura 3D printer</li>
</ul>
<p><strong>Media keys</strong></p>
<ul>
<li>2D design in Illustrator</li>
<li>Cut on laser cutter</li>
</ul>
<p><strong>Software</strong></p>
<ul>
<li>Code written in Arduino IDE</li>
</ul>
<h3 id="what-questions-need-to-be-answered">What questions need to be answered?</h3>
<ul>
<li>Can I write the software needed to integrate all the components, provide a user interface, and play music?</li>
<li>What kind of internal structure is needed to hold all the components in place, with stability, access where required, compactness and robustness?</li>
<li>Will the hardware and software platforms I’ve chosen be capable of handling the functional requirements of the system?</li>
<li>Can I combine these materials to create a device with the aesthetic qualities needed?</li>
<li>What other materials, finishes, trim, or processes could be used to make it a more aestheticly enjoyable device?</li>
</ul>
<h3 id="how-will-it-be-evaluated">How will it be evaluated?</h3>
<ul>
<li>Aesthetic quality – would this device look at home on the Nostromo?</li>
<li>Reliability in identifying media keys, SD card handling, user interface and music playback</li>
<li>Tactile feel (material finish, sound and haptic feedback of the controls, feel of the media cards, and placing/removing them from the device)</li>
<li>How is the experience of using the device to play music in the home. Does the constrained interface make listening to music more pleasurable?</li>
</ul>Andrew SleighMy plan for a final project.18 — Computer superpowers2018-05-30T00:00:00+01:002018-05-30T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/podcast/2018/05/30/podcast-18<p>Why I get excited about computers, some of my history with the Mac, and my ambivalence ahead of this year’s WWDC about Apple’s other platforms.</p>
<audio src="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep18.mp3" controls="" preload=""></audio>
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<p><a href="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep18.mp3">Direct link to mp3</a></p>
<p>Subscribe: <a href="https://itunes.apple.com/gb/podcast/unreliable-devices/id1340450476">Apple Podcasts</a> / <a href="http://fab.academany.org/2018/labs/fablabbrighton/students/andrew-sleigh/podcast.rss">RSS</a></p>
<hr />
<p>Podcast artwork uses an <a href="https://thenounproject.com/term/hand/930971/">illustration</a> by <a href="https://thenounproject.com/analalora/">Ana María Lora Macias</a>, licensed as Creative Commons CC-BY.</p>Andrew SleighWhy I get excited about computers, some of my history with the Mac, and my ambivalence ahead of this year’s WWDC about Apple’s other platforms.17 — Things that people want to make2018-05-24T00:00:00+01:002018-05-24T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/podcast/2018/05/24/podcast-17<p>This week, I’ve been making a casing for my project. There’s something satisfying about making a thing that looks finished. Maybe this is a way to help more people enjoy making things.</p>
<audio src="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep17.mp3" controls="" preload=""></audio>
<!--more-->
<p><a href="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep17.mp3">Direct link to mp3</a></p>
<p>Subscribe: <a href="https://itunes.apple.com/gb/podcast/unreliable-devices/id1340450476">Apple Podcasts</a> / <a href="http://fab.academany.org/2018/labs/fablabbrighton/students/andrew-sleigh/podcast.rss">RSS</a></p>
<hr />
<p>Podcast artwork uses an <a href="https://thenounproject.com/term/hand/930971/">illustration</a> by <a href="https://thenounproject.com/analalora/">Ana María Lora Macias</a>, licensed as Creative Commons CC-BY.</p>Andrew SleighThis week, I’ve been making a casing for my project. There’s something satisfying about making a thing that looks finished. Maybe this is a way to help more people enjoy making things.Week 17 - Wildcard Week2018-05-23T00:00:00+01:002018-05-23T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/assignments/2018/05/23/wk17-wildcard-week<p>For wildcard week, I’m testing different approaches, including composites, for making my final project casing.</p>
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<h2 id="setting-a-brief">Setting a brief</h2>
<p>The assignment this week is to: “design and produce something with a digital fabrication process (incorporating computer-aided design and manufacturing) not covered in another assignment, documenting the requirements that your assignment meets, and including everything necessary to reproduce it.”</p>
<p>I want to use this week to make progress on my final project, and in particular the project casing. For a project with a strong aesthetic element, this is an important part, and I don’t want to fall back to common makerspace approaches such as finger-jointed laser-cut ply boxes, or a 3D printed plastic case.</p>
<p>The tests I’m running are:</p>
<ul>
<li>Can I use composites to make either the main box, or just the side panels</li>
<li>Can I use folded metal to make the main part of the casing</li>
<li>Can I cut and score aluminium for a casing using the milling machine we have in the lab</li>
</ul>
<h2 id="cardboard-prototype">Cardboard prototype</h2>
<p>I started by making a simple card prototype to get a sense of the overall shape, size and assembly of my basic casing idea.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0942.jpg" alt="Cardboard box net cut on laser" /></p>
<p>It consists of a central folded part, with flat side panels that cover the folding tabs. These could be attached by bolts or rivets.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1065.jpg" alt="Folded box prototype" /></p>
<h2 id="composite-corner-test">Composite corner test</h2>
<p>My box needs good sharp corners, flat faces, and a good even surface texture. So I tried a simple composite test to see if I could make a folded box using this method.</p>
<p>I made a simple corner mold out of MDF, covering the interiors faces with vinyl to aid release.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0948.jpg" alt="Vinyl covering on mold" /></p>
<p>I used the 2-part Smooth-Cast 326 resin, and loose-woven hessian as my materials</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0956.jpg" alt="Mixing resin" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0964.jpg" alt="Painting resin onto hessian" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0977.jpg" alt="Placing hessian layers" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0966.jpg" alt="Pressing hessian into the corners" /></p>
<p>I applied 4 layers, then clamped the mold together inside</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0983.jpg" alt="Assembling the mold" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0985.jpg" alt="Clamping the mold" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0988.jpg" alt="Cured mold" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0990.jpg" alt="Mold dissassembled" /></p>
<p>The process worked pretty well; the composite is strong and light, though too flexible for my needs. Also, some of the texture of the hessian has come through to the outside face. Maybe this could be solved with a different kind of resin.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0993.jpg" alt="Cured part out of the mold" /></p>
<p>I also had quite a lot of air in the mix, which deteriorated the outside surface.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0994.jpg" alt="Sharp corner" /></p>
<h2 id="composite-side-panel-test">Composite side panel test</h2>
<p>Next, I wanted to try making a simpler part of the box, the side panels, which need to be strong, flat, have smooth faces, and resist damage.</p>
<p>I also wanted to try a different fibre, and also experiment with a sandwich construction, where the central layer is made of a lightweight material.</p>
<p>And I wanted to form the part with good surfaces out of the mold, so minimal post-processing would be necessary</p>
<p>I used Fusion 360 to model a mold part. The part is simple – an 8mm thick rounded rectangle – I added vent holes to allow excess resin to escape in a more controlled way, and I used the laser cutter to cut the second part of the mold – a simple flat lid.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1005.jpg" alt="Milled mold part" /></p>
<p>For the composite, I used 2 layers of cotton canvas, then a layer of corrugated cardboard, followed by two more layers of canvas.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1006.jpg" alt="Mold and material parts" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1019.jpg" alt="Applying resin to cotton canvas" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1025.jpg" alt="Fitting top plate of mold" /></p>
<p>I used clamps to compress the mold</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1028.jpg" alt="Clamping the mold" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1029.jpg" alt="Cured mold" /></p>
<p>The part released fine, but had a very poor surface finish. Some of this could perhaps be remedied with a finishing coat, though there were many voids in the edges, which would need a lot of filler to fix.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1032.jpg" alt="Cured part out of the mold" /></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1064.jpg" alt="Finished coupon" /></p>
<p>## Folded metal test</p>
<p>Metal would be the ideal material for my project. I want to create a device that wouldn’t look out of place in the <a href="http://alienanthology.wikia.com/wiki/USCSS_Nostromo">Nostromo</a>, so a rough, heavy-duty, industrial casing is the kind of look I’m going for.</p>
<p>But metal is difficult to form with the tools we have easy access to at the lab, so I wanted to try some tests to see what is feasible.</p>
<p>I started with a scrap piece of 2mm aluminium, and tried scoring it on the <strong>Roland MDX-50</strong> so that I could create precise folds.</p>
<p>Luiz used <strong><a href="https://www.cnccookbook.com/feed-speeds-calculator-gwizard/">GWizard</a></strong> software, to work out some initial feed and speed settings for our mill:</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/gwizard.jpeg" alt="G Wizard" /></p>
<p>We used <strong>Roland ClickMILL</strong> software to create simple 0.5mm deep score lines across the Aluminium.</p>
<p><strong>Test 1: 1mm flat-nosed bit, conservative settings</strong></p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/aluminium-mill-test-1-settings.JPG" alt="G Wizard" /></p>
<ul>
<li>Feed speed: 400mm/minute</li>
<li>Spindle speed: 15000 rpm/minute</li>
<li>Cut-in (depth of each pass): 0.25mm</li>
</ul>
<p>I wanted to try a very thin score line, so used the smallest bit we have. I used a conservative (slow) feed speed, with a high spindle speed (the highest our mill is capable of).</p>
<p>It cut successfully, but the milling did not produce a lot of clean chips, with residue building up along the cut line.</p>
<p><strong>Test 2: 1mm bit, higher speed</strong></p>
<ul>
<li>Feed speed: 500mm/minute</li>
<li>Spindle speed: 15000 rpm/minute</li>
</ul>
<p>Next, I tried another score line, at a higher speed. But there was no noticeable improvement in quality. Also, the drill bit broke on this setting. So next, we moved to a 3mm bit.</p>
<p><strong>Test 3: 3mm bit flat-nosed bit</strong></p>
<ul>
<li>Feed speed: 600mm/minute</li>
<li>Spindle speed: 15000 rpm/minute</li>
<li>Cut-in (depth of each pass): 0.1mm</li>
</ul>
<p>We also increased the speed for this test, and used a more conservative setting for the cut depth. The bit survived, but there was a lot of doughy swarf left in the cut line, which was being drawn into the drill bit as it passed back and forth.</p>
<p><strong>Test 4: 3mm bit flat-nosed bit</strong></p>
<ul>
<li>Feed speed: 900mm/minute</li>
<li>Spindle speed: 15000 rpm/minute</li>
<li>Cut-in (depth of each pass): 0.1mm</li>
</ul>
<p>Finally, we tried the same bit with a higher speed. This gave the cleanest cut, with small chips flying from the bit rather than staying in the cut.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1048.jpg" alt="Test scores" /></p>
<p>This is some of the soft waste material I removed from the test cuts.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1045.jpg" alt="Swarf" /></p>
<p>I was able to fold the metal in a vice just using my hands</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1049.jpg" alt="Clamping for folding" /></p>
<p>The fold was clean and precise. I was very happy with this result.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1051.jpg" alt="Fold test" /></p>
<p>## A simple box</p>
<p>Next, I tried creating a simple folded box, to test the scoring method and also cutting out the outline of the part.</p>
<p>I used Illustrator to create the box net, and then exported the artwork as PNGs so I could create cutting paths in Fab Modules.</p>
<p>I started by cutting the outline. I used the same settings as in the final tests. Immediately we hit a problem as the machine tried to mill the 4mm assembly holes, and caused the spindle to ‘experience overcurrent’.</p>
<p>So I cancelled the job, and generated new paths without the holes. I also changed the speed from 15mm/sec down to 10mm/sec.</p>
<p>However, this again caused an overload, so for the next attempt, I used the speed override on the machine itself to reduce the feed speed down to about 40% (i.e. 4mm/sec).</p>
<p>At this stage, we decided to cancel the job again, so we could cut the score lines, as we were worried the part ould move in the process of it being cut out. I narrowly avoided the mistake of setting the cut depth to the same as the material depth.</p>
<p>Then I went back ot the outline, and I was able to cut out the whole part in about an hour.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1059.jpg" alt="Outline and scoring finished" /></p>
<p>I used an electric drill to cut the assembly holes and a file to clean up the cut edges.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1061.jpg" alt="Drilling holes" /></p>
<p>Then I used a vice and pliers to fold the box. One set of corners, with diagonal cuts, folded well, the other set (with overlapping tabs) didn’t. I could probably make these work by offsetting the score lines for these tabs.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_1063.jpg" alt="Folded test box" /></p>
<p><a name="files"></a></p>
<div class="files">
<h2>Files</h2>
<p>Mold parts for side panel test</p>
<ul>
<li><a href="https://myhub.autodesk360.com/ue2dec5f7/g/shares/SH7f1edQT22b515c761e7f791b3eeb1ddac1?viewState=NoIgbgDAdAjCA0IDeAdEAXAngBwKZoC40ARXAZwEsBzAOzXjQEMyzd1C0AmR3AYwGYIMCAFoARjABmAThEAWaQHZcIxgDZ%2BADhG8xmgCYxFnffo2S0AXxABdIA">Wax block Fusion 360 public link</a></li>
<li><a href="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/files/wildcard/wax-block.stl">Wax block STL file</a></li>
</ul>
<p><strong>Folded metal test net:</strong></p>
<ul>
<li><a href="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/files/wildcard/aluminium-box-test-net.ai">Illustrator file</a></li>
<li><a href="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/files/wildcard/box-test-outline.png">Outline bitmap</a></li>
<li><a href="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/files/wildcard/box-test-holes.png">Holes bitmap</a></li>
<li><a href="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/files/wildcard/box-test-scoring.png">Scoring lines bitmap</a></li>
</ul>
</div>Andrew SleighFor wildcard week, I’m testing different approaches, including composites, for making my final project casing.Week 16 - More Machine Building2018-05-16T00:00:00+01:002018-05-16T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/assignments/2018/05/16/wk16-more-machine-building<p>Building a polargraph plotter. Part 2: testing, machine control and iteration</p>
<p>This is a group project with Paul and Sophie. <a href="http://fab.academany.org/2018/labs/fablabbrighton/penguino.html">Our group docs are here</a>.</p>
<p><!--more--></p>
<h3 id="testing-our-first-prototypes">Testing our first prototypes</h3>
<p>Before we tried controlling the Penguino with a computer, we tried moving the gears by hand. We tried tracing a simple drawing. We quickly learned that our gondola was not stable enough, and that there was a lot of slop in the chains, which we swinging back and forward. Our temporary drawing surface (corrugated card) also proved to be too flimsy.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0897.jpg" alt="" /></p>
<p>So while Paul got to work on the machine control code, I worked on a redesigned version of the gondola.</p>
<h3 id="gondola-version-2">Gondola version 2</h3>
<p>I wanted to make a gondola with a flat acrylic base, to aid smooth movement over the drawing surface. I used some existing PVC pipe (lined with closed cell foam) to hold the pen, and laser-cut the other parts to fit.</p>
<p>I used 1-part cast acrylic bonder to glue the parts together.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0900.jpg" alt="" /></p>
<p>We quickly found that the gondola needed more weight to keep the pen stable on the paper, so hacked a quick fix by taping bolts to the acrylic base.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0904.jpg" alt="" /></p>
<p>By this time, Paul had some control software working, so we able to try some computer-controlled test drawings.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0912.jpg" alt="" /></p>
<h3 id="gondola-version-3">Gondola version 3</h3>
<p>I wasn’t happy about the weight hack, so made another version of the gondola that could have bolts attached or removed as needed.</p>
<p>I made all the parts out of clear acrylic, so we could get a better view of the drawing in progress.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0914.jpg" alt="" />
<img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0916.jpg" alt="" /></p>
<p>Then we tried some more test prints. For these, we also made a more substantial bed for the drawing paper, to provide a rigid, stable drawing surface.</p>
<p><img src="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/images/IMG_0934.jpg" alt="" /></p>
<h3 id="video-of-the-penguino-in-action">Video of the Penguino in action</h3>
<iframe width="560" height="315" src="https://www.youtube.com/embed/fDa0sfZ-qXU?rel=0" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen=""></iframe>
<p><a name="files"></a></p>
<div class="files">
<h2>Files</h2>
<p><a href="/2018/labs/fablabbrighton/students/andrew-sleigh/assets/files/machine_building/penguino-gondola-v3.eps">Gondola version 3 parts for the laser cutter</a></p>
</div>Andrew SleighBuilding a polargraph plotter. Part 2: testing, machine control and iteration This is a group project with Paul and Sophie. Our group docs are here.16 — Making machines2018-05-16T00:00:00+01:002018-05-16T00:00:00+01:00/2018/labs/fablabbrighton/students/andrew-sleigh/podcast/2018/05/16/podcast-16<p>The pleasure in making something come to life.</p>
<audio src="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep16.mp3" controls="" preload=""></audio>
<!--more-->
<p><a href="http://media.blubrry.com/unreliable_devices/andrewsleigh.com/unreliable-devices/ep16.mp3">Direct link to mp3</a></p>
<p>Subscribe: <a href="https://itunes.apple.com/gb/podcast/unreliable-devices/id1340450476">Apple Podcasts</a> / <a href="http://fab.academany.org/2018/labs/fablabbrighton/students/andrew-sleigh/podcast.rss">RSS</a></p>
<hr />
<p>Podcast artwork uses an <a href="https://thenounproject.com/term/hand/930971/">illustration</a> by <a href="https://thenounproject.com/analalora/">Ana María Lora Macias</a>, licensed as Creative Commons CC-BY.</p>Andrew SleighThe pleasure in making something come to life.