Diary

4/22 Class Notes

Discussion: Shop Class as Soulcraft Ch. 7

• Chloe: People nowadays have a preference for algorithms instead of thinking
• Connor: Bureaucracy is an example of how algorithms are slowly replacing thinking.
• Dr. Littman: What is the idea behind this chess master?
• Ainsley: IBM was able to program a computer to beat a chess grandmaster because the computer had a massive database to draw from.
• Rashmiya: We do a lot better at thinking abstractly and generally than computers.
• Zane: There is a book where an EMP goes off and people had to turn to the 70+ year old experts, and were unable to rebuild society.
• Chloe: If you are going to draw information randomly then you will draw incorrect conclusions. I am confused about what he is talking about here.
• Dr. Littman: He gave an example about certain meters which are either accurate or precise – accurate meaning it is close to the correct value but not at a very close value. Precise meaning it is an extremely detailed value but it is not the actual value. With this meter, the needle keeps moving between the two.
• Chloe: He mentions the valves in this section
• Dr Littman: Engine group, how did you get the valves lined up?
• Eugene: We had to match the angles of the valves with the seating and apply a sort’ve paste while they rotated in order to get a nice, tight fit with the valves.
• Chloe: As a manual author, you are acting as a social interlocutor between the machine and the human. On one hand you have to be extremely technically savvy in order to understand the part, but you also have to be socially savvy in order to be able to explain the part in terms that makes sense for a wide array of people to be able to understand.
• Rashmiya: The guy who won the French scrabble championship didn’t speak any French. He just memorized a bunch of French words and was really good at Scrabble.

Chapter 8

• Chloe: A lot of the work we do on a daily basis is divided by this line. Part of what we do is work on getting our diploma, doing our homework, updating our LinkedIn. Then the other part is, for example, I go to dance practice because I want to do that work for the sake of leisure, for the intrinsic practice of dancing only due to my enjoyment of it.
• Nate: Americans live to work while the Spanish work to live.
• Dr. Littman: He uses the example of the Mortgage Broker. He works hard to make money so he can go on vacation. Certainly there are people who enjoy what they do for work. But for most people, working is just a means to make money so they can do things they enjoy.
• Chloe: I find it interesting that people who are attracted to things like engineering are also the people who are likely to make a practical decision for a career.
• Ainsley: Leisure is something that we do if we have time. It is not something that is built into our lives. There will always be reasons in your life to keep working and pursuing something. My friends in Sweden just work for 8 hours and then go have fun with their friends.
• Chloe: For me, dance is equally as important as my future career. For my friend who dances with me, her hobby is math.
• Dr. Littman: As you all get older, your perspective may change. Once you have kids and you need to start making different financial sacrifices, your outlook may change.
• Ben: I love coding, I will always be coding. I want to code for the rest of my life. I will be pursuing a less money-centric aspect of computer science. There may be times when I make less money but there are things like summer internships where I can make a bit more money.
• Chloe: Let’s look at pg. 186. I don’t know about you guys, but I am not taking this class just to look at some motorcycle spokes and walking away. I want to see the whole motorcycle come together. Thoughts?
• Ainsley: It is all about your personal values.
• Vanessa: When working in an office, the validation you get is from the approval of others, whereas with a mechanic, the validation they get is the car and motor turn on and are working properly.
• Zane: The way I look at each major is each major will cultivate a different skill. So really, it is more about the soft skills they gain while earning their degree. In short, it is not about the knowledge they gain, but the journey to acquire that knowledge.
• Dr Littman: The author talks about how the person who makes the Rolls Royce has great pride in his work product even though he doesn’t get to see his work product being used because it brings satisfaction to him, and maybe recognition to him among those in his community.
• Dr. Littman: In the next chapter, this comes back to the nature of work. Is it Darwinian? So people frolic in order to survive, or do they survive because they want to frolic. Pigs and dolphins. I think, again, it comes back to finding work that we like.
• Ainsley: There was this tiny little thing that if we reward children for drawing even though it is terrible then they keep drawing. But if they don’t get rewarded then they kinda go ok, whatever, it was kind’ve a slog to begin with, I think I will just give this up. I think we should stop telling children that they are good at something when they are not. Maybe break it to them when they are old enough: Hey, you are terrible at painting. Let’s focus on something else.
• Dr. Littman: He says that he isn’t preaching motorcycle mechanics for everybody. But really he is preaching to find something which you derive satisfaction from and do that thing.
• Dr. Littman: In the next section he talks about how he doesn’t really like India, but he sees something electricians dealing with some cables and he feels some solidarity with them because he understands electrical work.
• Chloe: Basically by saying forcing yourself into isolation in order to gain greater understanding of something forces you further into isolation and will eventually cause you to feel a lack of community for something.
• Dr. Littman: Alright, to wrap up, this book is about the importance of deriving pleasure from work.
• Remember: Monday at 12:30, food and photo.

4/20 Class Notes

Guest Lecture: Nanometers to Motorcycles

Dr. Aditya Soods

• Extreme temperatures in the combustion chamber: gases can get at hot as ~2,200C.
• Leads to high temperatures in the engine block critical for: safety, mechanical integrity, comfort.
• In the nanoscale, atoms vibrate. These vibrations are oscillations which speed up as they get hotter.
• At room temperature, atoms vibrate at a frequency of about 1013 hz.
• ”Phonons”: really high frequency atomic vibrations that carry heat in electrical insulators.
• Bulk vs nanoscale heat conduction: Fourier’s Law is used to determine the thermal conductivity of materials.
• Fourier’s law breaks down for nanoscale materials.
• Heat changes the properties of materials. When you heat up a metal, fewer of the atoms are touching. With fewer boundaries which block the path of atomic planes, it is easier to mold the metal.
• Thermal barrier shields are a difficult engineering problem due to the fact that most thermal insulators are mechanically soft, with low mass density.
• An example that takes inspiration from acoustics is using multiple layers of different materials with varying densities to manipulate the oscillations of materials in the atomic scale.
• Materials scientists use something called 2-d materials to fabricate layers of atomic structures on the nanoscale, stacking various structures on top of each other to produce thin materials with desirable properties.
• Another application of thermoelectric materials is the generation of electricity using N- and P-type semiconductor pellets between two ceramic substrates and applying heat to one side of the material.
• A great application of these materials is in spacecraft and car manufacturing – ~70% of the energy produced in the engine is lost as heat. That heat could instead be converted to electrical energy for the car, saving another ~5% of energy.
• This type of technology can also be applied in reverse to create a thermoelectric cooler.

Recap

• Engine team: replaced valves
• Clutch team: troubleshooting to figure out why the red motorcycle is no longer igniting. Decided that it is a wiring program and is tracing wires using the electrical diagram to find the problem.
• Wheel team: Ordered new rim strips, inner tubes, and tiered. Measured the leather seats and watched YouTube tutorials to learn how to properly sew new leather seats for the blue motorcycle.
• Electrical team: Worked on the electrical switch and bored new threads into the switch.

On Wednesday, the class will be finishing the final chapters of the Shop class as soul craft book

Presentations should be 15 minutes long on May 7th at 12:30 pm. There should be some science in it, does not need to be comprehensive. We can give a brief overview of everything we did, however the technical piece should be about one specific aspect of something we worked on. We will also post our presentations on the website. 8-10 slides. Graphics.

Meeting on Monday, may 27th to take a group photo.

Week 10: Precepts 4/13 and 4/15

Notes by Aminatou Seye <3

 

Previously in class…

Electrical group:

• Secured the ignition coil on the blue motorcycle, which was loose and vibrating when we started the motorcycle. 
• Drove the Model T throughout the friend center lawn. We also went to the MAE lab to find the crimping tool and tested it on a random wire found in the lab. 

Wheel group:

• Trued and tightened parts of the wheel and finished the rear wheel. The bearing got pressed in with a missing part, so we needed to knock it out and install a new one.  We also need a new liner, inner tube, and tire for the wheel. Another issue is that the spacer (looks like a washer) that contacts the outer race is missing, so we need to find a solution. 
• Drove the Model T throughout the friend center lawn. 

Engine Group:

• Grinded the seals down to 44 degrees instead of 45 degrees (it was supposed to be 46 degrees, but now it is below by 2 degrees, which is a problem that needs to be fixed).
• Drove the Model T throughout the friend center lawn. 

Clutch and Oil Group:

• Made sure the fasteners were tight, ensured that the Whitworth parts were in the correct position (as opposed to other types of threads), and started finding the neutral position of the carburetor. 
• Drove the Model T throughout the friend center lawn. Adjusted the timing of the spark using an ohmmeter (checking for beeping; when the points are open, there was no beeping because the magnetic field collapses, which causes a change of magnetic field and produces a high voltage, and when they are closed, the beeping started) on the red motorcycle. 

 

Exploring Chapter 5…

Head of Discussion: Aynslie

Section 1: The Further Education of a Gearhead: From Amateur to Professional:

• The author criticizes academia while uplifting learning trades and doing hands-on work. A possible source of this critique is that he viewed graduate school as a task that is seen as needed rather than something he enjoys and is passionate about. There also could be a factor of parental pressure, given that his father was a mathematical physicist, and he viewed it as too theory-based. 
• Motorcycle references: 
  • Cafe racer: lightweight bikes made for agility, originating from the British rocker subculture for racing between cafes.
  • Cleaning Supplies (e.g., electrical contact cleaner, carburetor cleaner, engine degreaser): made for taking away oils and residue
  • Lubrification: Cutting oil, lithium greases: used to reduce friction 

Section 2: The Motorcycle Antiquarian

• Different ideas of work: many people see work as a means to an end and value a 9-5 structured shift, while others like freer schedules and being a “free man”, like what Fred does, and what the authors aspired to do. 
• Definition: Impedance—in an electrical sense, it is when the current and voltage is not in phase; applies to capacitance and inductance. In this book, it refers to the resistance (measured in ohms). Impedance is important in a motor since it prevents overheating and maintains a healthy current flow. 

Section 3: Shockkoe Moto

• Theme: important to learn things the hard way and make your own mistakes so you can understand the why rather than blindly trusting old knowledge. 
  • In class, we compared this to the advice of either explaining to children why they aren’t allowed to do something or letting them make mistakes themselves so they can develop problem-solving skills. 

Section 4: Writing Service Tickets

• Motorcycle references: using a tap to thread things, removing the brass float needle on a carburetor (a component that stops or allows fuel flow from the tank).

 

Section 5:  Madness, a Magna, and Metaphysics

• Motorcycle reference: a valve train, multiple cylinders that are all connected with a camshaft that opens with a sequence, camshafts and rockers (components that control the timing and lift of the intake and exhaust valves), the clutch, master and slave cylinders.
  • Class lecture on hydraulic cylinder: One important principle in engineering is mechanical advantage: if you have a master cylinder with a small diameter and move it a large distance, it move a certain amount of fluid, if its a big cylinder that same liquid would move the same amount of distance, you need a lot of forces to deal with a surface that is not moving. This is governed by the work equation, where Work is force times displacement. 
• The author is saying to take broader concepts and use them to check yourself to make sure your decision in life is well thought out, and you’re not impulsively making decisions. He also urges readers to balance their own selfish, personal interests and recognize the balance between doing a good job and the right job. 

 

Exploring Chapter 6…

Head of Discussion: Hala

Section 1:  The Contradiction of the Cubicle

• Machine building is dictated by the object of reality: a machinist has an objective measure (i.e., an engine either works or doesn’t). On the other hand, in an office job, the metric is more subjective, and employees are often evaluated on how well they get along with the people around them.
• The author advocates for a balance between work and private life.
• A trend the class noticed: many jobs today are trying to make office jobs more fun and flexible. 

Section 2: Indexing and Abstracting

• The narrator tries to go back to work after a philosophy degree, but he couldn’t find a fulfilling job even though he had a master’s degree. He was distraught because he found that many office jobs he saw don’t care as much about quality, despite all the skills he spent a lot of time acquiring. He argues that physical environments (like the ones in which hardworking people operate), while corporate working is mentally challenging and harms your soul. 

Section 3-5: Indexing and Abstracting, Learned Irresponsibility, Interlude: What college is for

• The author argues that employers do not care about GPA. (The class found that this is only partially true. It is true that most employers want to know that you can pick up skills fast rather than your actual skills, but it depends on the major many times. Grades can be an indicator of whether you’re able to follow rules, for instance.) 

Section 6: Teamwork

• The author criticizes office work and says it is more about teamwork than individual responsibility. He also argues that corporate culture teaches you specific ways to approach a problem and to bond with people, which brainwashes people by controlling their entire day and actions. 

Section 7: The Crew versus the Team

• This section discusses the difference between the often interchangeably used terms of a team vs a crew.  A crew is a group of people with individual skills, like a group of electricians, plumbers, and carpenters. You need all of them working together to make a building, for example, but each group respects the others, and rather than having a whole team working on the same thing (as on a team), you break them up into different categories and let individuals develop separate skill sets. Thus, there is individual confidence in a crew.

 

4/13: About Model T 

• The motorcycle is not power-steering operated (manual steering). There are two levers on the steering column, the left lever is the spark advance, and when it is running, it moves from retarted to advance, and you will hear the engine change it sounds. Always start in the retarted position  (where the piston is already up and is about to come down)because the piston can cause the crankshaft to reverse its direction, which is really bad on a Model T. On the right-hand side of the column is the slide valve, the adjustment for the carburetor. This sets the engine speed: the more gas you give it, the faster it goes. Furthermore, the motorcycle also has three pedals. The left pedal is the shifter. This has three positions: when it’s pushed in, it is in low gear; when it’s halfway out, it is neutral; and when it’s all the way out, it is in high gear. The middle pedal governs whether or not you go in reverse. The right-hand pedal is the brake, specifically the drive shaft brake rather than the wheel brake. To stop, take your left foot off the clutch and put the right foot down. The starter is on the floorboard; it is a little button (the size of a computer mouse). It is very important NOT to push that down when the engine is running. 

 

4/6 discussion notes

 

• Going over how to edit the class website – join as admin
  • Adding a post is momentarily down
• Recap
  • Vanessa (wheel group): priming the front wheel hub
  • Aynslie (clutch): fixed pin attached to real, adjusted carburetor
  • Ben (engine group): cutting out gaskets for engine
  • Aminatou (electrical group): put kickstarter on the motorcycle
  • Eugene (engine group): in machine shop, widened barrel with a “hone” tool after measuring barrel with a telescoping gauge
  • Prof Littman: painted the hub, got it ready for the wheel group
• Photo of Prof Littman and Bill at Railroad Hall in Franklin Museum which Bill designed
  • They built a visitor operated mini railroad to allow visitors to dispatch trains and change tracks via remote control
  • They used the controls of a real Conrail locomotive, visitors saw what an engineer would see operating the train
  • Prof Littman shows video of the engineering model of the train exhibit

• Prof Littman posted Bill’s wheel talk and Prof Ferris’ engine and fuels talk
• Discussion of Chapter 4 in Shopclass as Soulcraft
  • Chloe (discussion leader): anyone have any thoughts about the first section of the chapter
    • Emily: It was interesting that the author says personalities should dictate career choices
    • Prof Littman: The two personalities were commanding and careful. In selecting a career, disposition is important, whereas in choosing a college you essentially take an iq test
    • Aynslie: I thought it was interesting that the author talked about the rise of medication in schoolchildren and high schoolers. Maybe this comes from a decline in recess and breaktime as people get older.
    • Vanessa: Kids are all pushed to sit down in class and be serious all day. Maybe some kids don’t learn best that way and need ways to release their energy that are different from seated concentration. Included anecdote about her brother who was diagnosed with ADHD
    • Prof Littman: In early America, there was discussion about boys beginning school when they are 10 years old
    • Vanessa: Scientifically we can understand when kids are best tailored to study and work (based on circadian rhythms) but society doesn’t always listen to these scientific findings.
    • Nate: Schooling is often crafted to serve an institutional purpose rather than our own personal development.
    • Aynslie: It’s interesting that later in college you aren’t made to sit all day, but earlier on in elementary and high school you are made to sit and concentrate more often and for longer periods

• Chloe: what did people take away about the story in the repair shop from section 2
  • Aynslie: I noticed he talked about packing a wheel bearing…
  • Vanessa: I packed a wheel bearing. We put a sticky grease lubricant in the bearings before putting them into the hub.
  • Bill: If you pack a bearing full of lubricant, the grease can’t move around in order to cover more of the bearing surface. This can cause a bearing to wear down or overheat.
  • Abby: Motorcycle term from later in the chapter
  • Prof Littman: It also mentions a transaxle. It’s the combination of a transmission differential and an axle, which some cars like Porsches have. He also mentions a flat 6.
  • Nate: A flat 6 gives lower rev but more output.
  • Bill: In a Porsche, a flat 6 is horizontal but not vertical.
  • Prof Littman: We are also introduced in this section to Lance. What is his deal?
  • Rashmina: Lance is the operator of the Porsche facility who the narrator works for, but he only gives the narrator busy work.
• Chloe: In the next section, the narrator talks about seeming like you know what you’re doing but not actually knowing. This was the string theory section.
  • Prof Littman: He talks about practical vs theoretical. The narrator’s physicist father talks about the theoretical shoelace which if you pull hard on one side it tightens. The narrator talks about the practical side, which would hold that pulling hard would cause the shoelace to break.
  • Chloe: Would anyone like to explain String Theory
  • Prof Littman: It’s called String theory because it is a way to understand particles in the universe. Scientists imagine matter is made up of strings that have resonances. The concept is that particles in nature are made up of “harmonics” like a string that is pulled. The big message in this section, however, has to do with the theoretical vs the practical. There is also another motorcycle term: gas shocks. A gas shock is a piston in a cylinder that is filled with air. 
• Chloe: The next section is called The Mentor and we meet a new hippy character named Chas who the narrator says introduces him to the “pleasure of metal”. It is quite a long chapter, but I wondered what you guys thought about the idea of metal as a complex theoretical material and about the idea of “selling” craftsmanship
  • Ben: People wanting to buy cars or items understand that they spend more for better craftsmanship and more speed. 
  • Prof Littman: Customers already know what they want, but maybe they need to be instructed to achieve it. Unrelated: I posted a resource about how head markings on bolts affect tensile strength and yield strength. The author also talks about ways of improving the engine on page 87.
    • He talks about tuning the engine to about 80 horsepower. What causes an engine stroke?
    • Nate: the revolution of the crank would be the full stroke
    • Prof Littman: If you wanted to increase the stroke, you would put the journal further away from the flywheel within the crankshaft
    • Also Prof Littman: You also want air to come in and out of the engine at high speed. 
    • Bill: A muffler is usually at the end of the exhaust pipe and it is a chamber that sound coming out of the exhaust pipe goes into so that when it comes out it is not as loud (it gets dissipated by physics in the muffler)
    • Prof Littman: Yes, the muffler affects the rate at which air comes in and leaves from the engine, which itself affects the power of the engine. If you wanted a more powerful car you would remove the muffler to get better car breathing.
    • Eugene: why would you want a light and fast flywheel. Isn’t the point of a flywheel to store energy so wouldn’t you want a lot of mass?
    • Bill: If you are starting and stopping cars quickly for racing, you want a lighter flywheel so that the mass doesn’t affect breaking as much. 
    • Prof Littman: The author also shows an image of and talks about match boarding. What is that? It is when you make certain that going from one piece to another piece of the engine, it is a smooth and compatible connection (from tube to tube for example).

• Chloe: The next section talks about blueprinting an engine. I think this means identifying the wear and tear of an engine and making sure the parts you put into an engine are usable and strong. To get us started in this section, it is interesting that my perception of why wheels changed by working with the motorcycle wheels and thinking about their alignment.
  • Bill: I teach a course on watercolor painting, and I go around and comment on other people’s paintings. I usually tell people to go walk around the room and then come back to their painting to look at it again with a different perspective.
  • Aynslie: In flying, you have to put complete faith in your flying instruments to see the bigger picture and not freak out or just focus on one thing while flying.
  • Prof Littman: I was thinking of the drawing of the skeleton. There is an exercise in painting where beginner painters are made to paint a face right side up and upside down. It usually looks better starting upside down because in that case you are thinking about the relationship between lines and angles without bias of thinking you know what a face looks like.
  • Abby: We also drew a skeleton in my high school.
  • Prof Littman: This section also talks about patterns of wear and mushrooming in engine valves and stems
• Chloe: The next section is on personal knowledge.
  • Nate: I really like the new definition and interpretation of what an “idiot” is. It talks about how mechanics who don’t really care about their craft are idiots because they aren’t embracing their public role.
• Chloe: The next section thinks about stopping to make sure you understand what problem you’re solving before moving to actually solve the problem. It is the issue of metacognition.
  • Emily: I think it was interesting to see the vulnerability involved in accepting you could be wrong in some way.
  • Chloe: Yes, I think this is something that I sometimes get stuck in, not wanting to admit a mistake. I like the way he framed this problem in honesty and humility.
• Chloe: Last section talks about how our perception of service workers as automated script readers should inform our decisions as consumers to seek out more authentic and dedicated service.
  • Nate: I thought about this when I worked at a restaurant. It seemed like pushing people to follow a script undermined the intellectual integrity and expression of the service workers.
  • Bill: I’m worried about this issue especially in the context of AI.
  • Prof Littman: Yes, I also think an understanding of the big picture of systems and applications could also get lost in the context of AI, because AI just seems to care about the minutiae.

• We also have to start to talk about the final presentation. Presentations should be group powerpoint presentations on small but interesting details of each motorcycle group.

 

4/8 Discussion Notes

 

• Class introductions to Professor Martinelli (guest speaker today)
• Prof Martinelli – originally from Rome, Italy – came to Princeton for grad school, never left (began teaching here), is an expert in fluid mechanics and locomotion
• His talk:
  • Computational fluid mechanics is at the intersection of engineering and computational mathematics
  • Fluids are usually opposing motion (Drag force)
    • A fluid flow goes from a laminar (organized) motion to a more disturbed and chaotic motion after coming into contact with an object in motion
  • Lift (force)
    • Keeps airplane in the air – generate lift by making use of fluid flow on the wing surface
    • Flow field behind the wing of an airplane is very messy (turbulent regime of fluid flow)
      • Lift is generated by the most turbulent, tornado-like fluid flow on the wings
        • This also generates drag
    • Professor Littman query – it is often taught that lift is generated by suction
      • Prof Martinelli says this explanation is not actually true
      • The control volume approach (that Prof Littman tends to use) is in the long-run accurate, but the more correct explanation comes from the vortexes of fluid generating lift by spinning in a certain direction
    • Other question about aspect ratio
      • Aspect ratio is fixed as a function of how the airplane is made – need stronger engine to overcome induced drag which is inevitable
  • Reynolds number
    • As you increase the Reynolds number, the drag in the wake of an object in motion becomes a far more turbulent regime and the drag’s diameter decreases
    • Adding dimples to a golf ball for example accelerates the process of increasing friction drag, creating more turbulence in the wake, and having the induced drag go down
  • In supersonic or subsonic speed fighter jets, the plane wings must be narrow to stay within the shock angle – less lift so stronger engines
  • Acoustic Field
    • Lots of interaction between the fluid dynamic structure and the acoustic field that is generated
      • Speech is the result of a very very small pressure disturbance that the listener detects and can decode as language

 

• Integrated resistance – propulsion – control
  • Sail boats with hydrofoil wing in the water with very large aspect ratio
    • This lifts the boat out of the water
  • Aerodynamic forces at work – two important parameters at work within Reynolds number (ratio of inertia over viscous forces)
• Venturi Effect
  • FOR AN INCOMPRESSIBLE FLOW, A REDUCTION OF AREA CAUSES AN INCREASE IN LOCAL FLOW VELOCITY AND A CONSEQUENT DECREASE IN PRESSURE
• Engine Cooling
  • Heat is dissipated through convective heat transfer
• External Aerodynamics
  • Wheel spraying water at passerby – the vortex structure behind the wheel as it moves forward picks up water off the ground and moves it laterally
    • This can be mitigated by changing the structure of the wheel hub to bend the vortex force and make the water’s spray not as problematic
• To make his models and simulations, Prof Martinelli uses GPU processing to visualize and compute forces on objects
  • There is some bottlenecking because with GPUs, getting data in and out takes a really long time
  • You have to maximize operation and minimize the translation with the GPU
  • The measurements of the simulation are accurate to a magnitude of a fifth order polynomial
• Stall
  • Bird flapping wings when it lands allows for a very large stall margin
  • If you want to do this in an airplane, you have to start flapping very fast
  • An airplane stall is an aerodynamic phenomenon where wings lose lift because the angle of attack (AoA) exceeds a critical point, disrupting smooth airflow
• Professor Martinelli also teaches the flight design course and the aerodynamics course at Princeton

Guest Lecture: Engine & Fuel Combustion (by Professor Alison Ferris)

The guest lecture focused on combustion science and how it applies to engines and propulsion systems. Professor Ferris works with chemical kinetics, which looks at how gas-phase molecules react under extreme conditions such as high temperature and pressure.

She talked about the difference between air-breathing engines (like turbojets), which take in oxygen from the surrounding air, and rocket engines, which carry both the fuel and the oxidizer. Her research is specifically dealing with hypersonic flight, where they test at temperatures from 400 K up to several thousand Kelvin in low-pressure conditions.

One major focus of her work is fuel design. Jet fuel is made up of a mixture or smoothie of hydrocarbons of different sizes. Some of these molecules tend to produce soot, which contributes to contrails, which is the visible trails left behind aircraft when they fly. While most/temporary contrails are fairly harmless, long-lasting contrails can form cirrus clouds which trap heat and contribute to global warming. Her research looks into how fuel composition can be tweaked to reduce these persistent contrails and soot formation to mitigate these environmental deteriments.

To study combustion, Professor Ferris uses shock tubes, which is a very narrow and long tube, to simulate engine-like conditions. These devices generate high-pressure shock waves (using helium) which heat up a fuel-air mixture. This allows researchers to observe combustion processes over a longer period of time, when usually this process occurs in milliseconds.

Professor Ferris also talked about engine knock. Engine knock occurs when fuel-air mixture ignites automatically too early due to high pressure and temperature. Instead of a smooth outward flame front (deflagration), knock creates pressure spikes which reduces efficiency and can damage the engine. Resistance to knock is measured by a fuel’s octane number. Octane number measures a fuels’ resistance to autoignition. Higher-performance engines (higher compression) need higher-octane fuels.

She also explained thermal efficiency, which measures how much of the fuel’s chemical energy is converted into work. In general, increasing the compression ratio improves efficiency, but only up to the point where knock becomes limiting. In the 1960s, additives like tetraethyllead were used to decrease knock, but these additives contained lead and were later phased out due to severe environmental and health consequences.

Finally, she compared internal combustion engines (like our motorcycle engine), which operate in cycles (intake, compression, combustion, exhaust), with gas turbines, which use continuous combustion. Gas turbines (used in jet engines and power plants) typically achieve only around 35% efficiency.

Lab Work

In lab this week, we continued restoring the motorcycle. We worked with a gasket, which is used to seal engine components and prevent oil leaks. We installed or prepared a gasket for the engine cover (unsure?).

We also started working on the electrical system, specifically with wiring and switches. We worked on connecting a wiring harness and looking at past examples of wiring and the Triumph manual.

Additionally, we talked about engine wear and measurement. We learned about cylinder reboring, which is when the cylinder diameter is slightly increased in increments (0.010 inches at a time) to restore a worn engine. This process can only be done a few times before having to insert a sleeve. We learned about tools such as a Mitutoyo bore gauge to measure cylinder diameter accurately.

We also talked about piston rings, which are needed to maintain compression. These rings seal the gap between the piston and cylinder wall, which prevents air and fuel from escaping. Bad or leaky sealing can reduce engine efficiency and cause blue smoke (oil burning) or white smoke (bad combustion). The third ring, the oil ring, specifically prevents oil from entering the combustion chamber.

Precept Discussion: Shop Class as Soulcraft (Chapter 1)

We talked about themes from chapter 1 of the book. We talked about the difference between economic value and moral value in different types of work. One idea was that trades like plumbing or mechanics are often highly valued economically but are not given the same social status/prestige as more “intellectual” professions.

We also talked about the concept of agency, which Crawford defined as the ability to act independently and take control of one’s work. In manual trades, this is very similar to competence, because there is a standard to when one knows they have done a satisfactory job. Knowing what you are doing and being able to solve real-world problems is part of agency. Mechanical work specifically often requires effort to identify problems first before solving them, as opposed to textbook math problems for example. Then we talked about the cognitive demands of manual labor, where, contrary to popular belief, manual labor is equally if not more intellectually rigorous. We also connected these ideas to automation/assembly lines and the idea of outsourcing labor costs.

Some motorcycle terminology:

Backfire: combustion occurs at the wrong time. Flames sent through the intake (often due to incorrect timing or air-fuel mixture).
Afterfire: unburned fuel ignites in the exhaust system which leads to popping sounds or flames from the exhaust, usually during deceleration.

Monday Notes

No recap

Presentation by Bill Becker – Discovering the Motorcycle Wheel

About Bill – retired architect, worked with Littman on toy trains at Franklin Institute. Did a lot of educational work, nonprofit work. Decided he wanted to work on motorcycles after retiring, been a long interest. Lots of shop experience, loves to make things and now focuses on antique toys and building them from scratch

Looking at wheel – through lens of materials, design, and physics

Round – good geometry for moving things

1790 – first bicycle, made out of wood and radial spokes

1885 – motorized bicycle, still wooden and radial spokes but has a transmission

1895 – no longer wood, metal spokes and metal hub, horizontal motor with jack shaft, back wheel has a filler and has a brake, block of wood that pushes down onto the wheel

1960 – tiger cub – spokes no longer radial and cross and triangulate, drive mechanism that drives the rear wheel

1960 – casting wheels that replace spokes

Today – cast wheels made out of carbon fiber strong and light

 

What are some major forces that played a role in the evolution of the motorcycle wheel?

• Need stronger wheels because motor power
• Materials improve and become better
• Depends on the surface the bike travels on, different wheels for paved areas vs mountain bikes
• Increased speeds

 

One of most important factors

Weight – make lighter

Wheels have inertia, so if it is heavy it takes more work to make it move

 

Response to forces – better design

Turning more requires different forces esp when faster, impact forces

 

Technology – better machinery

 

Materials in wheel

Each material has unique properties

• Strength
• Flexibility
• Hardness
• Workability (how easily it can be machined, malleable and ductible)
• Resistance to corrosion
• Conductivity
• Friction
• Cost

 

Materials in rim – mild steel sheet, rolled into correct profile, welded, plated with copper nickel and chromium

Needs to be strong rigid, workable, resistant to corrosion, cost effective, available

 

Cold vs Hot while machining – if hot then it is malleable and can change shape

If you heat tempered things then immediately cool it then it makes it stronger

Copper is opposite, depending on how it is cooled it can be hard or soft

 

Spokes – mild steel wire

Has to be strong efficient (small amount of material), workable, resistant to corrosion, cost, available

 

Hub

Attached motorcycle to wheel

Needs to be light weight, conducts heat, workable, natural resistance to corrosion, cost effective, available

Needs to conduct heat as tires get hot from braking

 

Bearings

Extremely hard, withstands wear, reduces friction, cost effective, available

 

Tire

Flexible, durable, moldable, resilient, high coefficient of fraction, cost effective, available 

 

Designers select materials based on their suitability for the task

Best performance at lowest cost = efficiency

 

What are the forces on our wheel?

Loads in engineering terms

• Dead loads = weight of the wheel itself and the motorcycle
• Live load = rider, passenger, gas and oil, luggage – the loads because of what we’re asking the motorcycle to do, asking it to carry passengers
• Static loads – loads when object at rest, wheels at rest – effects of gravity
• Dynamics loads – loads when moving, wheels in motion – effects of applying motor power and acceleration, effects of braking and deceleration, effects of turning the motorcycle, effects of striking an object – impact forces

 

Forces act in a directional manner, geometry of the wheel reacts to forces

Spokes are arranged in crosscrossing teams

Within ur teams you have 2 spokes that focus on acceleration and declaration and 2 spokes focus on side forces from turning

Loads are distributed in teams, better than radial

 

How do forces affect the elements within a structure?
5 basic forces acting on elements

• Compression, squeezing
• Tension, stretching/pulling
• Shear, trying to break molecular bond by cutting
• Bending, hybrid of compression and tension, middle of beam is neutral axis not affected
• Torsion

 

The tire is for cushioning the other elements from impact

The rim is purely compression ring that supports the tires

Spokes member the support fo the rim and the hub

Hub tension member that supports the spokes

 

The 20 top spokes provide tensile reaction when static

Spokes unable to hold compression by design, if compression it just pops out

 

The 20 backward leaning spokes provide tensile reaction when accelerating

 

20 right or left spokes provide tensile reaction when turning

 

in team

• 2 contribute to acceleration 
• 2 contribute to declaration
• 2 contribute to side to side

 

Applying forces to an element creates stress

And the reaction to the stress is strain

 

Young’s Modulus – stress strain diagram

 

Elastic region – strain goes back, not permanent

Plastic zone – deforms

 

The transition from elastic to plastic is at the yield point, amount of stress it can take drops before it starts to harden itself and reaches ultimate strength before breaking

 

Spokes must be tuned well as tightening one spoke affects a bunch of other spokes and you need everything in balance

 

Wednesday Notes

Rolled threads – stronger and higher quality than cut threads

Two rollers press into a bolt and molds the threads

 

If overtighten a screw, it stretched instead and if tightened too much it goes past yield point

 

The finer your thread, the more mechanical advantage, and the more likely you are to damage it

 

Steel is a hard material that can be magnetizied

Soft iron – pure iron which can be an electromagnet but can’t be a permanent magnet

 

Recap

Wheels – prepped bearings and worked on spokes with Bill, pressed in using arbor press

Electrical – sandblasting

Clutch/Oil – started old motorcycle, ran ok, at first no spark because no lead in, more adjustments need to be made for the engine, carburetor, and the timing. Also tighten all bolts

Engine – laser cut gaskets, took out studs and wrist pin from old engine, will try to hone the barrel instead of boring it

 

Chapter 3

The idea of dependency

Idea of learning by doing

Autonomy vs agency

Autonomy stereo , agency is playing musical instrument

you’re at the mercy of listening to what was already made, can’t play the things you want

 

Ikea – following someone else’s instructions, makes it feel like you did it yourself but you are given a solution

Makes it feel like you accomplished something

Also if you can’t do it, it puts the blame on you.

Ikea, Lego, Buildabear, are selling the idea that you did it yourself

Marketing makes you want to buy more, 

 

Not at complete liberty, even if you have 20 options you still have to pick a premade option

Hard to make your own custom things

To do things yourself takes more time than to use premade things

Power comes with agency

 

Wednesday 03/18/2026 

What Each Group Did on Monday

Wheel Group:

• Cleaned forks, removing oil before sandblasting
• Measured the leather seat dimensions

Electrical Group:

• Smoothed the kickstarter using emery paper so it is easier to remove
• Reinstalled the gasket

Clutch + Oil Group:

• Team 1:
  • Cleaned the clutch plates
  • Installed the clutch plates and springs
  • Plan: begin working on the carburetor
• Team 2:
  • Worked on the brakes
  • Identified that the brakes were loose and attempted to fix them

Top + Bottom End Group:

• Cleaned chains
• Used electrolysis to remove rust
• Calculated gear ratios

Demonstration: Rectifiers

• A rectifier has three visible electrodes and a fourth internal (hidden) connection
• We need DC (direct current) because the battery has a positive (+) and negative (–) terminal
• In motorcycles, the positive terminal is connected to ground
• The term ground comes from using the Earth as a conductor

Purpose of a Rectifier:

• Converts AC (alternating current) from the alternator into DC to charge the battery

Observations:

• The rectifier has four terminals:
  • Two labeled AC
  • One labeled +
  • One labeled –
• It operates using diodes

Circuit Simulator Explanation

• A simulation was shown using a 40 Hz AC source
• Color indicators:
  • Green = positive
  • Red = negative
• Yellow dots show the direction of current flow

Key Concepts:

• Current flows in one direction only in this setup
• A diode acts like a one-way valve for current

How AC is Converted to DC (Bridge Rectifier)

• Four diodes are arranged to form a bridge rectifier
• A resistor is placed in the circuit
• The AC source is connected to the bridge

How it works:

• Current takes a zigzag path through different diodes depending on the AC cycle
• Even when AC reverses direction, the output remains:
  • One side always positive
  • One side always negative

Application:

• The alternator acts as the AC source
• The battery receives the rectified DC output

Rectifier Testing Demonstration

• Red probe connected to AC terminal, black probe to negative terminal → reading of about 0.5 volts
• When leads are reversed → overload reading, meaning no current flows
• This demonstrates the one-way behavior of diodes

Discussion: Shop Class as Soulcraft by Matthew B. Crawford

Main Ideas:

• Emphasizes the value of manual labor and its intellectual demands
• Argues that repair skills are important and meaningful
• Suggests manual trades are a valid alternative career path to traditional academic routes

Craftsman vs. Tradesman:

• Craftsman: more personal, focused on mastery
• Tradesman: more economically practical and sustainable

Critique of Modern Work:

• In many office jobs, there is no clear objective measure of success
• In manual work, success is clearer:
  • If something works, the job was done well

Discussion of Part IV of Zen and the Art of Motorcycle Maintenance

Monday, 03/16/2026

• The ideas of mythos and logos connect with the concepts of the romantic and the classical.
• Aristotle is a teacher of rhetoric.
• There are three pillars of his argument:
  • Logos – logic
  • Ethos – credibility
  • Pathos – emotion
• If you balance these three, you will be more successful in persuasion.
• At first, the second identity (Phaedrus) appears and worries the narrator, but he realizes that by not opening the door, he is actually causing more trouble.
• At the end, they drive back to San Francisco, and Chris asks, “Were you crazy?” which releases the tension.
• Phaedrus comes across as more empathetic in times of cruelty.
• The narrator was fighting with Phaedrus until the end, but accepting him at the end is helpful for Chris.
• If the narrator had accepted him earlier, more interesting conversations might have happened.
• The narrator may have been unnecessarily cruel to Chris at the beginning, possibly because he could see that Chris wanted someone like Phaedrus as a father figure, and he did not want that version of himself to come out. Because of this, he may have judged Chris as well.
• Phaedrus and the narrator are both ill in their own different ways.
• The story has a sad ending, but the birth of his daughter makes it somewhat uplifting.

3/2/2026

Demonstration: strength of materials 

• As crank is turned, tension is placed on the wire
• A load cell is placed below to measure the force of the pull on the crosshead, measuring the tension in the wire → Measuring force and displacement
• Device measures “stress and strain,” which is similar to force and displacement
  • Stress is force per unit area
  • Strain is how much material deforms fractionally compared to its original form
• 7.8 x 10^-4 in^2 is original measurement made with calipers
• Wire snaps at force of approximately 33 pounds → means 42300 pounds per square inch can be endured given calculations 
  • High strength steel can endure at much as 200,000 pounds per square inch 
• When wire is plastically deforming, graph showing elasticity is no longer displaying a straight line → eventually reaches crest showing the maximum force of stretch that steel wire can endure
• This applied to suspension bridge cables and spokes of a wheel
• Wrought iron and other brittle materials snap rather than stretch 

Zen and the art of motorcycle maintenance 

Chapter 22

Motorcycle references: odometer, Harley High-Miler, and starter button (no need to discuss these)

• Phaedrus has breakthrough about quality
• Talks about Poincare and how science changed: science was no longer exact, but became “approximate” 
  • Absolute substance arises as idea of matter and intimatter: can convert matter into energy and vice versa
  • Absolute magnitude relates to uncertainty principle → again, showing how science is becoming approximate 
  • Einstein’s principle of equivalence shows that space is curved and light is curved 
  • Euclid and Reimann geometry creates discussion about what geometry is “right”
• Phaedrus claims that him and Poincare compliment each other in filling in gaps
  • Claims Poincare selects science and interpretation matching his own idea of beauty
• Convenience of mathematical and scientific models makes sense given the application
  • This ties together classical and romantic

Chapter 23

• Displays how narrator feels trapped inside body he has no control over, as if someone else is controlling him
• Feels 2 people living in the same body, with one of these people being taken away from his child
• Could suggest that the narrator has “gone too far” in his pursuit of Phaedrus

Chapter 24

• Explaining “stuckness” refers back to the narrator rather than referring to Phaedrus, suggesting that he is aware of his former closeness to Phaedrus

3/4/2026

Demonstration: spark tester

• Spark tester: one one end is spark plug, connected to in-line tester connected to cable 
• If there is a proper spark, there should be an orange spark in in-line tester
• When 80 volts is hit when the apparatus is hooked up to power supply the tester should light up

• When 80 volts is hit, the light became orange 
• When voltage is dropped any less, the light goes off 

• Light contains neon gas discharge, needing from 60-80 volts to light 
• When there is spark, current is able to flow through: one side of plug is at ground potential, the other is at high voltage 
• Bud light sign turns on when connected to power source 
  • red/orange part is neon → each gas has a characteristic color 
  • At certain angles with a diffraction grading, can see spectrum of color → same emission derived from fireworks 

Zen and the art of motorcycle maintenance: chapter 24

Motorcycle terms: stuck screw analogy is used

• Demonstration: screw extractors serve to drill pilot hole into screw, then jaw extractor and take screw out 

Content:

• Claims solution for people is caring and having connection to tasks → passion is imperative when completing a task 
• Claims scientific method does not contain hypothesis, creating idea that baseline knowledge is necessary
• Gives advice to chris for writing letter to his mother: to optimize quality, he suggests for Chris to write down all of his thoughts at once, and organize later → illustrates his explanation of stuckness

Zen and the art of motorcycle maintenance: chapter 25

Motorcycle terms: N/A

Content:

• Claims technology cannot be separated from art
• Starts discussing zen- ruminating combines classical and romantic by placing thought into both

Zen and the art of motorcycle maintenance: chapter 26

Motorcycle terms: overhauling an engine means tuning up the entire machine 

• Welders: there are different types of welders, used to merge materials via melting with high current and low voltage within an inner gas chamber containing rare gases (ie argon, neon, xenon, etc) to prevent rusting. 
  • A piece of metal has resistance; the amount of resistance increases reciprocally with cross-sectional area 

Content:

• Chapter primarily discusses gumption traps – gumption traps are phenomena that get in the way of the drive to continue a task 
• Internal and external gumption traps
  • Internal is more emotional side of traps → called hang-ups, where someone is getting in their own way
  • External are environment-dependent → called setbacks 
• Monkey getting hand stuck in jar  of rice scenario – can get more value through effort than giving up 
• Greek concept “arite” relates to quality discussion

Recap of last week’s work:

Clutch + Oil:

One group manufactured a part to tighten clutch; other team was researching the carburetor and how it works.

Top + Bottom End:

Cleaning parts; starting to move on to building the engine.

Wheels + Frame:

Cut spokes with bolt cutter, dissembled parts, made nuts more accessible by removing grease

Electrical:

Continued sandblasting main frame

Next Steps

• Putting a power coat and some of the parts in Philadelphia.
• Clutch Springs: Should be 1 21/32 of an inch.

Notes:

• Gasoline is a hydrocarbon. Oil is a mixture of many different hydrocarbons; when heating it up, the lighter substances bubble and vaporize. When distilling gasoline, start with crude oil, and warming it up. The first thing to come off is butane, then gasoline (octane: C8H18). To get better energy release, you have to get the best mixture of oxygen and gasoline (too little is lean, too much is rich). If it is too rich, unburned fuel with go out the exhaust pipe.
  • The calculation: C8H18 + 12.5 O^2 -> 8 CO2 + 9 H20
  • Exothermic reaction. Releases NOXs (nitrogen oxides, smog)
• The more power you have, the greater the acceleration. To get more energy out of the engine/per explosion:
  • Larger engine
  • Higher pressure in the engine
  • Pure oxygen instead of air
  • Use a fuel that has oxygen

Book Discussion:

• Quality is undefinable concept. Why is he trying to define it?
• Using students to find an answer to a difficult question.
• Pilgrimage to top of mountain India. While trying to analyze and understand philosophy, his physical strength and intellectual motivation wasn’t enough to get him to the top of the mountain. He doesn’t have a spiritual/mystic force pulling him upward; an egoist.
• “Quality is the cleavage term between hip and square.” Trying to bridge romantic and classical thought.
• He says, If we didn’t have quality, the world would be different. But is that a proof of existence?
• Art and beauty are not the same. 
• Biology often makes things way more energy efficient than robotics can imitate.

Emilly’s notes for 02/18/2024

Recap of last week’s work:

Engine Team:

Cleaned up both the small and the large components i.e., washers, using an ultrasonic cleaner (good for getting solvent into tiny spaces).

Wheel group:

Pulled out barring and retained the hardware inside.

Took the brakes apart and wheels off.

Clutch and oil:

They worked on fixing the clutch. They planned on using a piece of aluminum rod to create a cable stop.

Cons of making your own cable stop rather than purchasing: time-consuming, requires careful measurements.

Cons of using a 3D piece rather than metal: lacks material-strength, suitable material (better than aluminum) is steel.

Electric team:

Organized electrical components in the cabinet.

Sandblasted frames.

Interesting finding: found a crack on one of the frames.

ELECTRICAL COMPONENTS EXPERIMENT

Experiment 1:

Magnet on the middle part and coils on the side of a flat wooden surface.

The piece of laminated steel inside the coil generates voltage to get an LED blinking.

Based on Faraday’s law, voltage generates current, the greater the current, the brighter the LED.

Learnt: The alternator has 6 coils.

The coils have different diameters and different numbers of coils; the coils have different purposes. The coarser ones provide sufficient current to run the electrical system of the motorcycle. Some coils are for the ignition and some are for the horn system.

In the experiment;

The coils are wound in pairs.

The core is laminated, this is so to fix energy loss by restricting eddy currents to the coils.

Oscilloscope

The faster the spin, the higher the voltage. The voltage alternates from + to -.

The relationship between spinning and voltage is 1: 1(directly proportional).

Experiment 2: High voltage generator

Consist of; 

A primary and a secondary coil. The primary coil has fewer wire turns while the secondary coil has multiple turns.

Laminated core, contact, breakerpoints.

The setup becomes when we run current through the primary coil, contact is broken and the setup becomes a buzzer circuit.

When we slide the secondary coil over the primary coil, sparks are seen.

Magneto-electricity(Faraday) – magnetic field changing in time.

In an ignition coil, there is; 

A primary coil – this is coarse.

A secondary coil (has lots of turns for a higher voltage).

DISCUSSION

Reading: Chapters 14-16 in Zen and the Art of Motorcycle Design (no motorcycle references – care when riding a motorcycle over gravel as one can fall over easily).

CHAPTER 14

Discussion led by: David

Content

The narrator reflects over going to visit DeWeese. 

Question: Why does the author say that DeWeese is the living image of DeWeese as opposed to the man himself? He says so because he has no real memory of meeting DeWeese before thus he doesn’t have the personal experience that he should have as he interacted with him before as Phaedrus.

Triangular relationship between the narrator, John and DeWeese: John has a joking relationship with the author while DeWeese still sees the narrator as Phaedrus. Talk on quality; John doesn’t seem interested in deep talks that the narrator and DeWeese engage in. John and DeWeese know different forms of the narrator, they both talk to him as different people. DeWeese is defensive of the Phaedrus he knew and is kind towards the narrator. There is also a disconnect on knowledge of the narrator in both John and DeWeese, yet they both don’t know it.

DeWeese empathizes with the narrator because of his romantic view of life.

Dialogue:

DeWeese is upset with the instructions of a manual and wants the narrator to criticize it. DeWeese is interested in the sculptor’s view; if you can build it , you sculpt it.

The idea of peace of mind: to engineer something, one needs to approach it with the idea of doing it with a good calm mind, and take time in doing so. This relates to the lab; taking our time, approaching the motorcycle repair with the right attitude, and focusing on the process, not the completion.

Pg. 170 dialectic reason meaning and how it differs from a debate. Dialectic reason deals with discussion whose end result is truth while a debate is a discussion for the best argument win, not necessarily on truth.

What we learn about the narrator: teacher of rhetoric.

CHAPTER 15

Discussion led by: Vanessa

Content

Narrator’s relationship to Chris.

Chris’ fear when they go to the university and his fear of his dad, this suggests a throwback to a traumatic experience.

The narrator’s visit to the classroom and the effect that it has on him; closure, pain.

Sarah and the narrator talk on quality: what is quality and how do you know when it has been achieved? How do you evaluate the quality of an essay?

CHAPTER 16

Discussion led by: Chloe

Content

Self reflection at the beginning and religious allusions.

Question: What does the religious allusion tell us about the narrator?

Phaedrus tells the girl who had trouble writing an essay to look at the brick. This helped the girl get creative as it forced her to think about something new rather than what people tell her to do when writing.

Reflection: Phaedrus’ talks about grading and knowledge oriented students and how it applies to ourselves as students and the plot in general. 

Lack of grading:

Idealism – grading shouldn’t be a motivating factor for learning thus grades should be eliminated. (Phaedrus’ argument).

Realism (class’ opinions): Grades provide feedback, people go to school to get credentials, others make it a career.

People interested in a subject become fanatically interested in it and read, not necessarily grades as a motivating factor for them.

The idea that most students would leave university when grading is dropped (according to Phaedrus) is not real as people would still join universities for credentials.