March - June| 2019

I had this project for ME203: Design and Manufacturing. The goal was to use the tools of the Stanford Product Realization Lab (sand casting, mill, lathe, welding, sheet forming) to create something that was meaningful to us. For my project, I chose to build something that would remind me of where my engineering career began. Using the mill, lathe, and sand casting, I built Seal the Day.

Legos and chess have shaped who I am. When I was 6, it began as a mere interest when my parents gave me a Star Wars Lego set for one of my birthdays. I loved the minifigures and how I could recreate movie scenes. As I collected more sets and became more cognizant of the potential in them, I became more interested in the fact that the same few blocks could be permuted into so many different iconic sets, recreating things I saw in movies or life. Chess began as a hobby but grew into a much deeper appreciation. I loved the strategy. With the same set of rules, so many different outcomes could occur. In both, I learned that the simple can be combined into artful elegance and seeded my interest in engineering. I wanted to learn how the world as we know it was governed by only a few, elegant equations.

In pursuing elegance, and as a respite from endless variables and numbers, I began picking up handwritten missives as a hobby. For me, cursive captured both time and personality; every person has a different handwriting style. Thus, I started making my own cards, both for letters and general notes. I figured that notes that were personalized were far more meaningful, especially on special occasions. I also found the time and attention in writing neatly very therapeutic as it let me let go of all my stress and think on something else.

Most recently in grad school, I began exchanging letters with a pen pal. After receiving one of her letters and thinking about it over the day, I always look forward to getting home to reply. In the letters, she usually shares all about the highs and lows she’s had recently. As I write, I feel the burden of all the homework and school lift off my shoulders. I don’t feel bogged down and downtrodden, but I soar. I’m flying as I write my own experiences and thoughts. Usually, I notice that much more time has passed than I originally thought, but that’s ok. It’s spent on something that brings my joy. I pull my wax melter from my desk. Igniting the candle, I patiently wait for the wax to melt. Watching, I see the wildness of the flame and how they dance around the wax cup. Even more interesting, the wax begins to change from the clean diamond shape into an amorphous blob then finally a puddle: a rich, metallic puddle. Carefully, slowly, I pour the wax onto the envelope, and quickly, I grab my seal. Checking the alignment, I press gently into the paper, making sure the imprint comes out clean. Lifting away, I see my favorite Lego head smile back at me. It’s my seal, my personality stamped onto that letter.

In the design phase, I was most worried about how I was going to attach the cast seal with the handle body. Originally, I wanted what I thought was the simplest solution: a press fit. This would make it more or less permanent though. Lee however suggested that a threaded attachment would be a far better solution. She posited that it was not as difficult as I thought it was. Truth be told, I wasn’t as confident as she was, but I trusted her and went with that design for attachment. For the body, I originally intended for there to only be one main body part that would be turned together on the lathe using just the compound rest. While the design did hint at using a lathe to realize it, I still was not as familiar with the lathe to see the predict the issues that would later present themselves. Lastly, for the cross, I was confident that it would be a relatively straightforward process on the mill and would be the simplest part to make. Looking back, I’m very happy to see the progression of my overall design. Below is a glimpse at the change in overall design. From breaking apart the body to changing the seal, the original was quite different from the end result.

After 4-5 sessions of practice and exploring as well as finding many hidden problems, I began working on possibly final parts in earnest. For my critical parts that I saw as most challenging and potentially most time-consuming, I wanted to tackle the main body top and seal. Having made a seal design I was happy with, I used the Form 2 to make a higher fidelity print to use as my mold. From the Foundry TA’s, I decided to use a loose pattern for my cast seal to make the overall prep work less intensive. For the gate and runner, I simply used scrap wood. I traced the design out, cut, and sanded it to shape. The seal design had all the proper drafts and angles, but at the end of the day, pulling the pattern was quite difficult. After numerous attempts, I did finally manage to pull the pattern as close to perfectly as I wanted. Picking up my seal the next day was quite nerve wracking, but the result was worth it. It came out well and worked well with the letter wax that I had. The finishing step for this part was to clamp it on the mill with step clamps, drill a hole, then tap it.

One of the most anguishing processes was making the main body top piece. By far, this part had the most fleshed out operational sequence. During my practice, I adhered to it strictly and for my final practice of this piece, I used actual material. This practice was later lumped into what I thought could be a part that would end up on my final project. Everything went quite smoothly given the relatively extensive practice I spent on each feature. Using plenty of oil and slower speeds, I was able to use the compound stock to get a relatively even finish on the taper. Since the amount of stock in the 3 jaw chuck was quite short, I used a live center to ensure stability. The external thread tool also worked very well for my ring decorations. Unfortunately, on the very final step, parting it off the stock, I made an error of judgment and had to restart. The parting tool got stuck in a “valley” of sorts and slid to the right, cutting into the decorative rings. This was by far the most anguished moment over the project. I was so frustrated and disappointed that I messed up good work. However, the day after, having cooled down, I came back in to reattempt it. I learned that I needed to add the critical step of making a flush surface to cut on when parting. I also parted much further from the part I wanted to keep. This second attempt proved a little faster because I had done it once before.

The cross was the most straightforward part but still offered useful lessons. In my quest to be “more efficient”, I had prepared slices of square stock to use on the mill. My first cross unfortunately came out very lopsided since none of the arms were in line. At first, I was very confused why this result occurred since I had so carefully used the DRO to get accurate points. I then realized it was most likely due to me making those precut tablets. Since the parallel sides were so thin, the first facing operation likely wasn’t truly perpendicular and this cascaded into none of the faces being true. To remedy this, I started the second attempt from the full stock, faced, then cut. This proved much more accurate and solved the lopsided problem.

The final part I made was the lower body. Turning the taper was akin to that of the top part. The difficulty of this part was using the die to make the threads. I used a die in this case because I needed threads all the way down to the bottom of the shaft. This way, I would have enough threads to steadily grip the piece. Using the die was straightforward. It involved me placing the correct size die into the die holder and rotating it on the shaft.

The project turned out well, all thanks to the many TA's in the class that provided great guidance and advice. Special thanks to Professor Dave Beach who exhibited amazing energy and passion in class, and Lee Marom, my coach, who spent countless hours helping me solve problems and gave lots of positive reinforcement.